fetch config once

* Add some pool settings

* fmt

.circleci/config.yml

@@ -46,6 +46,14 @@ jobs:
           POSTGRES_PASSWORD: postgres
           POSTGRES_INITDB_ARGS: --auth-local=scram-sha-256 --auth-host=scram-sha-256 --auth=scram-sha-256
 
+      - image: postgres:14
+        command: ["postgres", "-p", "10432", "-c", "shared_preload_libraries=pg_stat_statements"]
+        environment:
+          POSTGRES_USER: postgres
+          POSTGRES_DB: postgres
+          POSTGRES_PASSWORD: postgres
+          POSTGRES_INITDB_ARGS: --auth-local=md5 --auth-host=md5 --auth=md5
+
     # Add steps to the job
     # See: https://circleci.com/docs/2.0/configuration-reference/#steps
     steps:

.circleci/pgcat.toml

@@ -39,7 +39,7 @@ log_client_connections = false
 log_client_disconnections = false
 
 # Reload config automatically if it changes.
-autoreload = true
+autoreload = 15000
 
 # TLS
 tls_certificate = ".circleci/server.cert"

.circleci/run_tests.sh

@@ -19,6 +19,7 @@ PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 5432 -U postgres -f tests/sharding/q
 PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 7432 -U postgres -f tests/sharding/query_routing_setup.sql
 PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 8432 -U postgres -f tests/sharding/query_routing_setup.sql
 PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 9432 -U postgres -f tests/sharding/query_routing_setup.sql
+PGPASSWORD=postgres psql -e -h 127.0.0.1 -p 10432 -U postgres -f tests/sharding/query_routing_setup.sql
 
 PGPASSWORD=sharding_user pgbench -h 127.0.0.1 -U sharding_user shard0 -i
 PGPASSWORD=sharding_user pgbench -h 127.0.0.1 -U sharding_user shard1 -i

.editorconfig

@@ -0,0 +1,14 @@
+root = true
+
+[*]
+trim_trailing_whitespace = true
+insert_final_newline = true
+
+[*.rs]
+indent_style = space
+indent_size = 4
+max_line_length = 120
+
+[*.toml]
+indent_style = space
+indent_size = 2

.rustfmt.toml

@@ -0,0 +1,2 @@
+edition = "2021"
+hard_tabs = false

CONFIG.md

@@ -49,6 +49,14 @@ default: 30000 # milliseconds
 
 How long an idle connection with a server is left open (ms).
 
+### server_lifetime
+```
+path: general.server_lifetime
+default: 86400000 # 24 hours
+```
+
+Max connection lifetime before it's closed, even if actively used.
+
 ### idle_client_in_transaction_timeout
 ```
 path: general.idle_client_in_transaction_timeout
@@ -108,7 +116,7 @@ If we should log client disconnections
 ### autoreload
 ```
 path: general.autoreload
-default: false
+default: 15000
 ```
 
 When set to true, PgCat reloads configs if it detects a change in the config file.
@@ -152,7 +160,7 @@ default: <UNSET>
 example: "server.cert"
 ```
 
-Path to TLS Certficate file to use for TLS connections
+Path to TLS Certificate file to use for TLS connections
 
 ### tls_private_key
 ```
@@ -213,7 +221,7 @@ If the client doesn't specify, PgCat routes traffic to this role by default.
 `replica` round-robin between replicas only without touching the primary,
 `primary` all queries go to the primary unless otherwise specified.
 
-### query_parser_enabled (experimental)
+### query_parser_enabled
 ```
 path: pools.<pool_name>.query_parser_enabled
 default: true
@@ -234,7 +242,7 @@ If the query parser is enabled and this setting is enabled, the primary will be
 load balancing of read queries. Otherwise, the primary will only be used for write
 queries. The primary can always be explicitly selected with our custom protocol.
 
-### sharding_key_regex (experimental)
+### sharding_key_regex
 ```
 path: pools.<pool_name>.sharding_key_regex
 default: <UNSET>
@@ -256,7 +264,40 @@ Current options:
 `pg_bigint_hash`: PARTITION BY HASH (Postgres hashing function)
 `sha1`: A hashing function based on SHA1
 
-### automatic_sharding_key (experimental)
+### auth_query
+```
+path: pools.<pool_name>.auth_query
+default: <UNSET>
+example: "SELECT $1"
+```
+
+Query to be sent to servers to obtain the hash used for md5 authentication. The connection will be
+established using the database configured in the pool. This parameter is inherited by every pool
+and can be redefined in pool configuration.
+
+### auth_query_user
+```
+path: pools.<pool_name>.auth_query_user
+default: <UNSET>
+example: "sharding_user"
+```
+
+User to be used for connecting to servers to obtain the hash used for md5 authentication by sending the query
+specified in `auth_query_user`. The connection will be established using the database configured in the pool.
+This parameter is inherited by every pool and can be redefined in pool configuration.
+
+### auth_query_password
+```
+path: pools.<pool_name>.auth_query_password
+default: <UNSET>
+example: "sharding_user"
+```
+
+Password to be used for connecting to servers to obtain the hash used for md5 authentication by sending the query
+specified in `auth_query_user`. The connection will be established using the database configured in the pool.
+This parameter is inherited by every pool and can be redefined in pool configuration.
+
+### automatic_sharding_key
 ```
 path: pools.<pool_name>.automatic_sharding_key
 default: <UNSET>
@@ -289,7 +330,8 @@ path: pools.<pool_name>.users.<user_index>.username
 default: "sharding_user"
 ```
 
-Postgresql username
+PostgreSQL username used to authenticate the user and connect to the server
+if `server_username` is not set.
 
 ### password
 ```
@@ -297,7 +339,26 @@ path: pools.<pool_name>.users.<user_index>.password
 default: "sharding_user"
 ```
 
-Postgresql password
+PostgreSQL password used to authenticate the user and connect to the server
+if `server_password` is not set.
+
+### server_username
+```
+path: pools.<pool_name>.users.<user_index>.server_username
+default: <UNSET>
+example: "another_user"
+```
+
+PostgreSQL username used to connect to the server.
+
+### server_password
+```
+path: pools.<pool_name>.users.<user_index>.server_password
+default: <UNSET>
+example: "another_password"
+```
+
+PostgreSQL password used to connect to the server.
 
 ### pool_size
 ```
@@ -328,7 +389,7 @@ default: [["127.0.0.1", 5432, "primary"], ["localhost", 5432, "replica"]]
 
 Array of servers in the shard, each server entry is an array of `[host, port, role]`
 
-### mirrors (experimental)
+### mirrors
 ```
 path: pools.<pool_name>.shards.<shard_index>.mirrors
 default: <UNSET>

Cargo.lock

@@ -4,9 +4,9 @@ version = 3
 
 [[package]]
 name = "aho-corasick"
-version = "0.7.20"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cc936419f96fa211c1b9166887b38e5e40b19958e5b895be7c1f93adec7071ac"
+checksum = "67fc08ce920c31afb70f013dcce1bfc3a3195de6a228474e45e1f145b36f8d04"
 dependencies = [
  "memchr",
 ]
@@ -28,13 +28,24 @@ checksum = "bddcadddf5e9015d310179a59bb28c4d4b9920ad0f11e8e14dbadf654890c9a6"
 
 [[package]]
 name = "async-trait"
-version = "0.1.66"
+version = "0.1.68"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b84f9ebcc6c1f5b8cb160f6990096a5c127f423fcb6e1ccc46c370cbdfb75dfc"
+checksum = "b9ccdd8f2a161be9bd5c023df56f1b2a0bd1d83872ae53b71a84a12c9bf6e842"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.9",
+]
+
+[[package]]
+name = "atomic_enum"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6227a8d6fdb862bcb100c4314d0d9579e5cd73fa6df31a2e6f6e1acd3c5f1207"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
 ]
 
 [[package]]
@@ -83,6 +94,12 @@ version = "3.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0d261e256854913907f67ed06efbc3338dfe6179796deefc1ff763fc1aee5535"
 
+[[package]]
+name = "byteorder"
+version = "1.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
+
 [[package]]
 name = "bytes"
 version = "1.4.0"
@@ -175,7 +192,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "scratch",
- "syn",
+ "syn 1.0.109",
 ]
 
 [[package]]
@@ -192,7 +209,7 @@ checksum = "086c685979a698443656e5cf7856c95c642295a38599f12fb1ff76fb28d19892"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
 ]
 
 [[package]]
@@ -246,6 +263,12 @@ version = "1.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "de853764b47027c2e862a995c34978ffa63c1501f2e15f987ba11bd4f9bba193"
 
+[[package]]
+name = "fallible-iterator"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4443176a9f2c162692bd3d352d745ef9413eec5782a80d8fd6f8a1ac692a07f7"
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -254,9 +277,9 @@ checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
 [[package]]
 name = "futures"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "13e2792b0ff0340399d58445b88fd9770e3489eff258a4cbc1523418f12abf84"
+checksum = "23342abe12aba583913b2e62f22225ff9c950774065e4bfb61a19cd9770fec40"
 dependencies = [
  "futures-channel",
  "futures-core",
@@ -269,9 +292,9 @@ dependencies = [
 
 [[package]]
 name = "futures-channel"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2e5317663a9089767a1ec00a487df42e0ca174b61b4483213ac24448e4664df5"
+checksum = "955518d47e09b25bbebc7a18df10b81f0c766eaf4c4f1cccef2fca5f2a4fb5f2"
 dependencies = [
  "futures-core",
  "futures-sink",
@@ -279,15 +302,15 @@ dependencies = [
 
 [[package]]
 name = "futures-core"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ec90ff4d0fe1f57d600049061dc6bb68ed03c7d2fbd697274c41805dcb3f8608"
+checksum = "4bca583b7e26f571124fe5b7561d49cb2868d79116cfa0eefce955557c6fee8c"
 
 [[package]]
 name = "futures-executor"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8de0a35a6ab97ec8869e32a2473f4b1324459e14c29275d14b10cb1fd19b50e"
+checksum = "ccecee823288125bd88b4d7f565c9e58e41858e47ab72e8ea2d64e93624386e0"
 dependencies = [
  "futures-core",
  "futures-task",
@@ -296,38 +319,38 @@ dependencies = [
 
 [[package]]
 name = "futures-io"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bfb8371b6fb2aeb2d280374607aeabfc99d95c72edfe51692e42d3d7f0d08531"
+checksum = "4fff74096e71ed47f8e023204cfd0aa1289cd54ae5430a9523be060cdb849964"
 
 [[package]]
 name = "futures-macro"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "95a73af87da33b5acf53acfebdc339fe592ecf5357ac7c0a7734ab9d8c876a70"
+checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.9",
 ]
 
 [[package]]
 name = "futures-sink"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f310820bb3e8cfd46c80db4d7fb8353e15dfff853a127158425f31e0be6c8364"
+checksum = "f43be4fe21a13b9781a69afa4985b0f6ee0e1afab2c6f454a8cf30e2b2237b6e"
 
 [[package]]
 name = "futures-task"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dcf79a1bf610b10f42aea489289c5a2c478a786509693b80cd39c44ccd936366"
+checksum = "76d3d132be6c0e6aa1534069c705a74a5997a356c0dc2f86a47765e5617c5b65"
 
 [[package]]
 name = "futures-util"
-version = "0.3.26"
+version = "0.3.28"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9c1d6de3acfef38d2be4b1f543f553131788603495be83da675e180c8d6b7bd1"
+checksum = "26b01e40b772d54cf6c6d721c1d1abd0647a0106a12ecaa1c186273392a69533"
 dependencies = [
  "futures-channel",
  "futures-core",
@@ -364,9 +387,9 @@ dependencies = [
 
 [[package]]
 name = "h2"
-version = "0.3.15"
+version = "0.3.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5f9f29bc9dda355256b2916cf526ab02ce0aeaaaf2bad60d65ef3f12f11dd0f4"
+checksum = "66b91535aa35fea1523ad1b86cb6b53c28e0ae566ba4a460f4457e936cad7c6f"
 dependencies = [
  "bytes",
  "fnv",
@@ -453,9 +476,9 @@ checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
 [[package]]
 name = "hyper"
-version = "0.14.24"
+version = "0.14.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e011372fa0b68db8350aa7a248930ecc7839bf46d8485577d69f117a75f164c"
+checksum = "ab302d72a6f11a3b910431ff93aae7e773078c769f0a3ef15fb9ec692ed147d4"
 dependencies = [
  "bytes",
  "futures-channel",
@@ -716,16 +739,18 @@ dependencies = [
 
 [[package]]
 name = "pgcat"
-version = "1.0.0"
+version = "1.0.1"
 dependencies = [
  "arc-swap",
  "async-trait",
+ "atomic_enum",
  "base64",
  "bb8",
  "bytes",
  "chrono",
  "env_logger",
  "exitcode",
+ "fallible-iterator",
  "futures",
  "hmac",
  "hyper",
@@ -737,8 +762,11 @@ dependencies = [
  "once_cell",
  "parking_lot",
  "phf",
+ "pin-project",
+ "postgres-protocol",
  "rand",
  "regex",
+ "rustls",
  "rustls-pemfile",
  "serde",
  "serde_derive",
@@ -750,6 +778,7 @@ dependencies = [
  "tokio",
  "tokio-rustls",
  "toml",
+ "webpki-roots",
 ]
 
 [[package]]
@@ -782,7 +811,7 @@ dependencies = [
  "phf_shared",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
 ]
 
 [[package]]
@@ -794,6 +823,26 @@ dependencies = [
  "siphasher",
 ]
 
+[[package]]
+name = "pin-project"
+version = "1.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ad29a609b6bcd67fee905812e544992d216af9d755757c05ed2d0e15a74c6ecc"
+dependencies = [
+ "pin-project-internal",
+]
+
+[[package]]
+name = "pin-project-internal"
+version = "1.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "069bdb1e05adc7a8990dce9cc75370895fbe4e3d58b9b73bf1aee56359344a55"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.9"
@@ -806,6 +855,24 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
 
+[[package]]
+name = "postgres-protocol"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "78b7fa9f396f51dffd61546fd8573ee20592287996568e6175ceb0f8699ad75d"
+dependencies = [
+ "base64",
+ "byteorder",
+ "bytes",
+ "fallible-iterator",
+ "hmac",
+ "md-5",
+ "memchr",
+ "rand",
+ "sha2",
+ "stringprep",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.17"
@@ -814,18 +881,18 @@ checksum = "5b40af805b3121feab8a3c29f04d8ad262fa8e0561883e7653e024ae4479e6de"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.51"
+version = "1.0.53"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5d727cae5b39d21da60fa540906919ad737832fe0b1c165da3a34d6548c849d6"
+checksum = "ba466839c78239c09faf015484e5cc04860f88242cff4d03eb038f04b4699b73"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.23"
+version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8856d8364d252a14d474036ea1358d63c9e6965c8e5c1885c18f73d70bff9c7b"
+checksum = "4424af4bf778aae2051a77b60283332f386554255d722233d09fbfc7e30da2fc"
 dependencies = [
  "proc-macro2",
 ]
@@ -871,9 +938,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.7.1"
+version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "48aaa5748ba571fb95cd2c85c09f629215d3a6ece942baa100950af03a34f733"
+checksum = "ac6cf59af1067a3fb53fbe5c88c053764e930f932be1d71d3ffe032cbe147f59"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -882,9 +949,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.28"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "456c603be3e8d448b072f410900c09faf164fbce2d480456f50eea6e25f9c848"
+checksum = "b6868896879ba532248f33598de5181522d8b3d9d724dfd230911e1a7d4822f5"
 
 [[package]]
 name = "ring"
@@ -917,14 +984,14 @@ dependencies = [
 
 [[package]]
 name = "rustls"
-version = "0.20.8"
+version = "0.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fff78fc74d175294f4e83b28343315ffcfb114b156f0185e9741cb5570f50e2f"
+checksum = "07180898a28ed6a7f7ba2311594308f595e3dd2e3c3812fa0a80a47b45f17e5d"
 dependencies = [
  "log",
  "ring",
+ "rustls-webpki",
  "sct",
- "webpki",
 ]
 
 [[package]]
@@ -936,6 +1003,16 @@ dependencies = [
  "base64",
 ]
 
+[[package]]
+name = "rustls-webpki"
+version = "0.100.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d6207cd5ed3d8dca7816f8f3725513a34609c0c765bf652b8c3cb4cfd87db46b"
+dependencies = [
+ "ring",
+ "untrusted",
+]
+
 [[package]]
 name = "scopeguard"
 version = "1.1.0"
@@ -960,19 +1037,19 @@ dependencies = [
 
 [[package]]
 name = "serde"
-version = "1.0.154"
+version = "1.0.160"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8cdd151213925e7f1ab45a9bbfb129316bd00799784b174b7cc7bcd16961c49e"
+checksum = "bb2f3770c8bce3bcda7e149193a069a0f4365bda1fa5cd88e03bca26afc1216c"
 
 [[package]]
 name = "serde_derive"
-version = "1.0.154"
+version = "1.0.160"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4fc80d722935453bcafdc2c9a73cd6fac4dc1938f0346035d84bf99fa9e33217"
+checksum = "291a097c63d8497e00160b166a967a4a79c64f3facdd01cbd7502231688d77df"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.9",
 ]
 
 [[package]]
@@ -1054,9 +1131,9 @@ checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
 [[package]]
 name = "sqlparser"
-version = "0.32.0"
+version = "0.33.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0366f270dbabb5cc2e4c88427dc4c08bba144f81e32fbd459a013f26a4d16aa0"
+checksum = "355dc4d4b6207ca8a3434fc587db0a8016130a574dbcdbfb93d7f7b5bc5b211a"
 dependencies = [
  "log",
 ]
@@ -1094,6 +1171,17 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "syn"
+version = "2.0.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0da4a3c17e109f700685ec577c0f85efd9b19bcf15c913985f14dc1ac01775aa"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
 [[package]]
 name = "termcolor"
 version = "1.2.0"
@@ -1157,18 +1245,17 @@ checksum = "d266c00fde287f55d3f1c3e96c500c362a2b8c695076ec180f27918820bc6df8"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
 ]
 
 [[package]]
 name = "tokio-rustls"
-version = "0.23.4"
+version = "0.24.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c43ee83903113e03984cb9e5cebe6c04a5116269e900e3ddba8f068a62adda59"
+checksum = "e0d409377ff5b1e3ca6437aa86c1eb7d40c134bfec254e44c830defa92669db5"
 dependencies = [
  "rustls",
  "tokio",
- "webpki",
 ]
 
 [[package]]
@@ -1187,9 +1274,9 @@ dependencies = [
 
 [[package]]
 name = "toml"
-version = "0.7.2"
+version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7afcae9e3f0fe2c370fd4657108972cbb2fa9db1b9f84849cefd80741b01cb6"
+checksum = "b403acf6f2bb0859c93c7f0d967cb4a75a7ac552100f9322faf64dc047669b21"
 dependencies = [
  "serde",
  "serde_spanned",
@@ -1208,9 +1295,9 @@ dependencies = [
 
 [[package]]
 name = "toml_edit"
-version = "0.19.4"
+version = "0.19.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a1eb0622d28f4b9c90adc4ea4b2b46b47663fde9ac5fafcb14a1369d5508825"
+checksum = "08de71aa0d6e348f070457f85af8bd566e2bc452156a423ddf22861b3a953fae"
 dependencies = [
  "indexmap",
  "serde",
@@ -1339,7 +1426,7 @@ dependencies = [
  "once_cell",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
  "wasm-bindgen-shared",
 ]
 
@@ -1361,7 +1448,7 @@ checksum = "2aff81306fcac3c7515ad4e177f521b5c9a15f2b08f4e32d823066102f35a5f6"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 1.0.109",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
@@ -1383,13 +1470,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "webpki"
-version = "0.22.0"
+name = "webpki-roots"
+version = "0.23.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f095d78192e208183081cc07bc5515ef55216397af48b873e5edcd72637fa1bd"
+checksum = "aa54963694b65584e170cf5dc46aeb4dcaa5584e652ff5f3952e56d66aff0125"
 dependencies = [
- "ring",
- "untrusted",
+ "rustls-webpki",
 ]
 
 [[package]]

Cargo.toml

@@ -1,10 +1,9 @@
 [package]
 name = "pgcat"
-version = "1.0.0"
+version = "1.0.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
 [dependencies]
 tokio = { version = "1", features = ["full"] }
 bytes = "1"
@@ -20,7 +19,7 @@ serde_derive = "1"
 regex = "1"
 num_cpus = "1"
 once_cell = "1"
-sqlparser = "0.32.0"
+sqlparser = "0.33.0"
 log = "0.4"
 arc-swap = "1"
 env_logger = "0.10"
@@ -29,7 +28,7 @@ hmac = "0.12"
 sha2 = "0.10"
 base64 = "0.21"
 stringprep = "0.1"
-tokio-rustls = "0.23"
+tokio-rustls = "0.24"
 rustls-pemfile = "1"
 hyper = { version = "0.14", features = ["full"] }
 phf = { version = "0.11.1", features = ["macros"] }
@@ -37,6 +36,12 @@ exitcode = "1.1.2"
 futures = "0.3"
 socket2 = { version = "0.4.7", features = ["all"] }
 nix = "0.26.2"
+atomic_enum = "0.2.0"
+postgres-protocol = "0.6.5"
+fallible-iterator = "0.2"
+pin-project = "1"
+webpki-roots = "0.23"
+rustls = { version = "0.21", features = ["dangerous_configuration"] }
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 jemallocator = "0.5.0"

README.md

@@ -21,20 +21,53 @@ PostgreSQL pooler and proxy (like PgBouncer) with support for sharding, load bal
 | Client TLS | **Stable** | Clients can connect to the pooler using TLS/SSL. |
 | Client/Server authentication | **Stable** | Clients can connect using MD5 authentication, supported by `libpq` and all Postgres client drivers. PgCat can connect to Postgres using MD5 and SCRAM-SHA-256. |
 | Live configuration reloading | **Stable** | Identical to PgBouncer; all settings can be reloaded dynamically (except `host` and `port`). |
+| Auth passthrough | **Stable** | MD5 password authentication can be configured to use an `auth_query` so no cleartext passwords are needed in the config file.|
 | Sharding using extended SQL syntax | **Experimental** | Clients can dynamically configure the pooler to route queries to specific shards. |
 | Sharding using comments parsing/Regex | **Experimental** | Clients can include shard information (sharding key, shard ID) in the query comments. |
-| Automatic sharding | **Experimental** | PgCat can parse queries detect sharding keys automatically, and route queries to the route shard. |
+| Automatic sharding | **Experimental** | PgCat can parse queries, detect sharding keys automatically, and route queries to the correct shard. |
 | Mirroring | **Experimental** | Mirror queries between multiple databases in order to test servers with realistic production traffic. |
 
 
 ## Status
 
-PgCat is stable and used in production to serve hundreds of thousands of queries per second. Some features remain experimental and are being actively developed. They are optional and can be enabled through configuration.
+PgCat is stable and used in production to serve hundreds of thousands of queries per second.
 
-| | |
-|-|-|
-|<a href="https://tech.instacart.com/adopting-pgcat-a-nextgen-postgres-proxy-3cf284e68c2f"><img src="./images/instacart.webp" height="70" width="auto"></a>|<a href="https://postgresml.org/blog/scaling-postgresml-to-one-million-requests-per-second"><img src="./images/postgresml.webp" height="70" width="auto"></a>|
-| [Instacart](https://tech.instacart.com/adopting-pgcat-a-nextgen-postgres-proxy-3cf284e68c2f) | [PostgresML](https://postgresml.org/blog/scaling-postgresml-to-one-million-requests-per-second) |
+<table>
+  <tr>
+    <td>
+      <a href="https://tech.instacart.com/adopting-pgcat-a-nextgen-postgres-proxy-3cf284e68c2f">
+        <img src="./images/instacart.webp" height="70" width="auto">
+      </a>
+    </td>
+    <td>
+      <a href="https://postgresml.org/blog/scaling-postgresml-to-one-million-requests-per-second">
+        <img src="./images/postgresml.webp" height="70" width="auto">
+      </a>
+    </td>
+    <td>
+      <a href="https://onesignal.com">
+        <img src="./images/one_signal.webp" height="70" width="auto">
+      </a>
+    </td>
+  </tr>
+  <tr>
+    <td>
+      <a href="https://tech.instacart.com/adopting-pgcat-a-nextgen-postgres-proxy-3cf284e68c2f">
+        Instacart
+      </a>
+    </td>
+    <td>
+      <a href="https://postgresml.org/blog/scaling-postgresml-to-one-million-requests-per-second">
+        PostgresML
+      </a>
+    </td>
+    <td>
+      OneSignal
+    </td>
+  </tr>
+</table>
+
+Some features remain experimental and are being actively developed. They are optional and can be enabled through configuration.
 
 ## Deployment
 
@@ -79,7 +112,7 @@ pgbench -t 1000 -p 6432 -h 127.0.0.1 --protocol extended
 
 See [sharding README](./tests/sharding/README.md) for sharding logic testing.
 
-Additionally, all features are tested with Ruby, Python, and Rust tests unit and integration tests.
+Additionally, all features are tested with Ruby, Python, and Rust unit and integration tests.
 
 Run `cargo test` to run Rust unit tests.
 
@@ -98,7 +131,7 @@ You can open a Docker development environment where you can debug tests easier.
 ./dev/script/console
 ```
 
-This will open a terminal in an environment similar to that used in tests. In there, you can compile the pooler, run tests, do some debugging with the test environment, etc. Objects compiled inside the contaner (and bundled gems) will be placed in `dev/cache` so they don't interfere with what you have on your machine.
+This will open a terminal in an environment similar to that used in tests. In there, you can compile the pooler, run tests, do some debugging with the test environment, etc. Objects compiled inside the container (and bundled gems) will be placed in `dev/cache` so they don't interfere with what you have on your machine.
 
 ## Usage
 

dev/docker-compose.yaml

@@ -26,6 +26,8 @@ x-common-env-pg:
 services:
   main:
     image: kubernetes/pause
+    ports:
+      - 6432
 
   pg1:
     <<: *common-definition-pg
@@ -56,6 +58,13 @@ services:
       POSTGRES_INITDB_ARGS: --auth-local=scram-sha-256 --auth-host=scram-sha-256 --auth=scram-sha-256
       PGPORT: 9432
     command: ["postgres", "-p", "9432", "-c", "shared_preload_libraries=pg_stat_statements", "-c", "pg_stat_statements.track=all", "-c", "pg_stat_statements.max=100000"]
+  pg5:
+    <<: *common-definition-pg
+    environment:
+      <<: *common-env-pg
+      POSTGRES_INITDB_ARGS: --auth-local=md5 --auth-host=md5 --auth=md5
+      PGPORT: 10432
+    command: ["postgres", "-p", "5432", "-c", "shared_preload_libraries=pg_stat_statements", "-c", "pg_stat_statements.track=all", "-c", "pg_stat_statements.max=100000"]
 
   toxiproxy:
     build: .
@@ -69,6 +78,7 @@ services:
       - pg2
       - pg3
       - pg4
+      - pg5
 
   pgcat-shell:
     stdin_open: true

examples/docker/pgcat.toml

@@ -38,9 +38,6 @@ log_client_connections = false
 # If we should log client disconnections
 log_client_disconnections = false
 
-# Reload config automatically if it changes.
-autoreload = false
-
 # TLS
 # tls_certificate = "server.cert"
 # tls_private_key = "server.key"
@@ -76,7 +73,7 @@ query_parser_enabled = true
 
 # If the query parser is enabled and this setting is enabled, the primary will be part of the pool of databases used for
 # load balancing of read queries. Otherwise, the primary will only be used for write
-# queries. The primary can always be explicitely selected with our custom protocol.
+# queries. The primary can always be explicitly selected with our custom protocol.
 primary_reads_enabled = true
 
 # So what if you wanted to implement a different hashing function,

pgcat.toml

@@ -23,6 +23,9 @@ connect_timeout = 5000 # milliseconds
 # How long an idle connection with a server is left open (ms).
 idle_timeout = 30000 # milliseconds
 
+# Max connection lifetime before it's closed, even if actively used.
+server_lifetime = 86400000 # 24 hours
+
 # How long a client is allowed to be idle while in a transaction (ms).
 idle_client_in_transaction_timeout = 0 # milliseconds
 
@@ -45,7 +48,7 @@ log_client_connections = false
 log_client_disconnections = false
 
 # When set to true, PgCat reloads configs if it detects a change in the config file.
-autoreload = false
+autoreload = 15000
 
 # Number of worker threads the Runtime will use (4 by default).
 worker_threads = 5
@@ -57,10 +60,16 @@ tcp_keepalives_count = 5
 # Number of seconds between keepalive packets.
 tcp_keepalives_interval = 5
 
-# Path to TLS Certficate file to use for TLS connections
-# tls_certificate = "server.cert"
+# Path to TLS Certificate file to use for TLS connections
+# tls_certificate = ".circleci/server.cert"
 # Path to TLS private key file to use for TLS connections
-# tls_private_key = "server.key"
+# tls_private_key = ".circleci/server.key"
+
+# Enable/disable server TLS
+server_tls = false
+
+# Verify server certificate is completely authentic.
+verify_server_certificate = false
 
 # User name to access the virtual administrative database (pgbouncer or pgcat)
 # Connecting to that database allows running commands like `SHOW POOLS`, `SHOW DATABASES`, etc..
@@ -113,6 +122,21 @@ primary_reads_enabled = true
 # `sha1`: A hashing function based on SHA1
 sharding_function = "pg_bigint_hash"
 
+# Query to be sent to servers to obtain the hash used for md5 authentication. The connection will be
+# established using the database configured in the pool. This parameter is inherited by every pool
+# and can be redefined in pool configuration.
+# auth_query = "SELECT $1"
+
+# User to be used for connecting to servers to obtain the hash used for md5 authentication by sending the query
+# specified in `auth_query_user`. The connection will be established using the database configured in the pool.
+# This parameter is inherited by every pool and can be redefined in pool configuration.
+# auth_query_user = "sharding_user"
+
+# Password to be used for connecting to servers to obtain the hash used for md5 authentication by sending the query
+# specified in `auth_query_user`. The connection will be established using the database configured in the pool.
+# This parameter is inherited by every pool and can be redefined in pool configuration.
+# auth_query_password = "sharding_user"
+
 # Automatically parse this from queries and route queries to the right shard!
 # automatic_sharding_key = "data.id"
 
@@ -123,17 +147,30 @@ idle_timeout = 40000
 connect_timeout = 3000
 
 # User configs are structured as pool.<pool_name>.users.<user_index>
-# This secion holds the credentials for users that may connect to this cluster
+# This section holds the credentials for users that may connect to this cluster
 [pools.sharded_db.users.0]
-# Postgresql username
+# PostgreSQL username used to authenticate the user and connect to the server
+# if `server_username` is not set.
 username = "sharding_user"
-# Postgresql password
+
+# PostgreSQL password used to authenticate the user and connect to the server
+# if `server_password` is not set.
 password = "sharding_user"
+
+pool_mode = "session"
+
+# PostgreSQL username used to connect to the server.
+# server_username = "another_user"
+
+# PostgreSQL password used to connect to the server.
+# server_password = "another_password"
+
 # Maximum number of server connections that can be established for this user
 # The maximum number of connection from a single Pgcat process to any database in the cluster
 # is the sum of pool_size across all users.
 pool_size = 9
 
+
 # Maximum query duration. Dangerous, but protects against DBs that died in a non-obvious way.
 # 0 means it is disabled.
 statement_timeout = 0
@@ -178,6 +215,8 @@ sharding_function = "pg_bigint_hash"
 username = "simple_user"
 password = "simple_user"
 pool_size = 5
+min_pool_size = 3
+server_lifetime = 60000
 statement_timeout = 0
 
 [pools.simple_db.shards.0]

src/admin.rs

@@ -1,10 +1,11 @@
 use crate::pool::BanReason;
-/// Admin database.
 use bytes::{Buf, BufMut, BytesMut};
 use log::{error, info, trace};
 use nix::sys::signal::{self, Signal};
 use nix::unistd::Pid;
 use std::collections::HashMap;
+/// Admin database.
+use std::sync::atomic::Ordering;
 use std::time::{SystemTime, UNIX_EPOCH};
 use tokio::time::Instant;
 
@@ -12,9 +13,7 @@ use crate::config::{get_config, reload_config, VERSION};
 use crate::errors::Error;
 use crate::messages::*;
 use crate::pool::{get_all_pools, get_pool};
-use crate::stats::{
-    get_address_stats, get_client_stats, get_pool_stats, get_server_stats, ClientState, ServerState,
-};
+use crate::stats::{get_client_stats, get_pool_stats, get_server_stats, ClientState, ServerState};
 use crate::ClientServerMap;
 
 pub fn generate_server_info_for_admin() -> BytesMut {
@@ -158,7 +157,14 @@ where
         "free_clients".to_string(),
         client_stats
             .keys()
-            .filter(|client_id| client_stats.get(client_id).unwrap().state == ClientState::Idle)
+            .filter(|client_id| {
+                client_stats
+                    .get(client_id)
+                    .unwrap()
+                    .state
+                    .load(Ordering::Relaxed)
+                    == ClientState::Idle
+            })
             .count()
             .to_string(),
     ]));
@@ -166,7 +172,14 @@ where
         "used_clients".to_string(),
         client_stats
             .keys()
-            .filter(|client_id| client_stats.get(client_id).unwrap().state == ClientState::Active)
+            .filter(|client_id| {
+                client_stats
+                    .get(client_id)
+                    .unwrap()
+                    .state
+                    .load(Ordering::Relaxed)
+                    == ClientState::Active
+            })
             .count()
             .to_string(),
     ]));
@@ -178,7 +191,14 @@ where
         "free_servers".to_string(),
         server_stats
             .keys()
-            .filter(|server_id| server_stats.get(server_id).unwrap().state == ServerState::Idle)
+            .filter(|server_id| {
+                server_stats
+                    .get(server_id)
+                    .unwrap()
+                    .state
+                    .load(Ordering::Relaxed)
+                    == ServerState::Idle
+            })
             .count()
             .to_string(),
     ]));
@@ -186,7 +206,14 @@ where
         "used_servers".to_string(),
         server_stats
             .keys()
-            .filter(|server_id| server_stats.get(server_id).unwrap().state == ServerState::Active)
+            .filter(|server_id| {
+                server_stats
+                    .get(server_id)
+                    .unwrap()
+                    .state
+                    .load(Ordering::Relaxed)
+                    == ServerState::Active
+            })
             .count()
             .to_string(),
     ]));
@@ -248,28 +275,15 @@ where
 
     let mut res = BytesMut::new();
     res.put(row_description(&columns));
-    for (user_pool, pool) in get_all_pools() {
-        let def = HashMap::default();
-        let pool_stats = all_pool_stats
-            .get(&(user_pool.db.clone(), user_pool.user.clone()))
-            .unwrap_or(&def);
 
-        let pool_config = &pool.settings;
+    for ((_user_pool, _pool), pool_stats) in all_pool_stats {
         let mut row = vec![
-            user_pool.db.clone(),
-            user_pool.user.clone(),
-            pool_config.pool_mode.to_string(),
+            pool_stats.database(),
+            pool_stats.user(),
+            pool_stats.pool_mode().to_string(),
         ];
-        for column in &columns[3..columns.len()] {
-            let value = match column.0 {
-                "maxwait" => (pool_stats.get("maxwait_us").unwrap_or(&0) / 1_000_000).to_string(),
-                "maxwait_us" => {
-                    (pool_stats.get("maxwait_us").unwrap_or(&0) % 1_000_000).to_string()
-                }
-                _other_values => pool_stats.get(column.0).unwrap_or(&0).to_string(),
-            };
-            row.push(value);
-        }
+        pool_stats.populate_row(&mut row);
+        pool_stats.clear_maxwait();
         res.put(data_row(&row));
     }
 
@@ -400,7 +414,7 @@ where
     for (id, pool) in get_all_pools().iter() {
         for address in pool.get_addresses_from_host(host) {
             if !pool.is_banned(&address) {
-                pool.ban(&address, BanReason::AdminBan(duration_seconds), -1);
+                pool.ban(&address, BanReason::AdminBan(duration_seconds), None);
                 res.put(data_row(&vec![
                     id.db.clone(),
                     id.user.clone(),
@@ -617,7 +631,6 @@ where
         ("avg_wait_time", DataType::Numeric),
     ];
 
-    let all_stats = get_address_stats();
     let mut res = BytesMut::new();
     res.put(row_description(&columns));
 
@@ -625,15 +638,10 @@ where
         for shard in 0..pool.shards() {
             for server in 0..pool.servers(shard) {
                 let address = pool.address(shard, server);
-                let stats = match all_stats.get(&address.id) {
-                    Some(stats) => stats.clone(),
-                    None => HashMap::new(),
-                };
 
                 let mut row = vec![address.name(), user_pool.db.clone(), user_pool.user.clone()];
-                for column in &columns[3..] {
-                    row.push(stats.get(column.0).unwrap_or(&0).to_string());
-                }
+                let stats = address.stats.clone();
+                stats.populate_row(&mut row);
 
                 res.put(data_row(&row));
             }
@@ -673,16 +681,16 @@ where
 
     for (_, client) in new_map {
         let row = vec![
-            format!("{:#010X}", client.client_id),
-            client.pool_name,
-            client.username,
-            client.application_name.clone(),
-            client.state.to_string(),
-            client.transaction_count.to_string(),
-            client.query_count.to_string(),
-            client.error_count.to_string(),
+            format!("{:#010X}", client.client_id()),
+            client.pool_name(),
+            client.username(),
+            client.application_name(),
+            client.state.load(Ordering::Relaxed).to_string(),
+            client.transaction_count.load(Ordering::Relaxed).to_string(),
+            client.query_count.load(Ordering::Relaxed).to_string(),
+            client.error_count.load(Ordering::Relaxed).to_string(),
             Instant::now()
-                .duration_since(client.connect_time)
+                .duration_since(client.connect_time())
                 .as_secs()
                 .to_string(),
         ];
@@ -724,19 +732,20 @@ where
     res.put(row_description(&columns));
 
     for (_, server) in new_map {
+        let application_name = server.application_name.read();
         let row = vec![
-            format!("{:#010X}", server.server_id),
-            server.pool_name,
-            server.username,
-            server.address_name,
-            server.application_name,
-            server.state.to_string(),
-            server.transaction_count.to_string(),
-            server.query_count.to_string(),
-            server.bytes_sent.to_string(),
-            server.bytes_received.to_string(),
+            format!("{:#010X}", server.server_id()),
+            server.pool_name(),
+            server.username(),
+            server.address_name(),
+            application_name.clone(),
+            server.state.load(Ordering::Relaxed).to_string(),
+            server.transaction_count.load(Ordering::Relaxed).to_string(),
+            server.query_count.load(Ordering::Relaxed).to_string(),
+            server.bytes_sent.load(Ordering::Relaxed).to_string(),
+            server.bytes_received.load(Ordering::Relaxed).to_string(),
             Instant::now()
-                .duration_since(server.connect_time)
+                .duration_since(server.connect_time())
                 .as_secs()
                 .to_string(),
         ];

src/auth_passthrough.rs

@@ -0,0 +1,134 @@
+use crate::errors::Error;
+use crate::pool::ConnectionPool;
+use crate::server::Server;
+use log::debug;
+
+#[derive(Clone, Debug)]
+pub struct AuthPassthrough {
+    password: String,
+    query: String,
+    user: String,
+}
+
+impl AuthPassthrough {
+    /// Initializes an AuthPassthrough.
+    pub fn new(query: &str, user: &str, password: &str) -> Self {
+        AuthPassthrough {
+            password: password.to_string(),
+            query: query.to_string(),
+            user: user.to_string(),
+        }
+    }
+
+    /// Returns an AuthPassthrough given the pool configuration.
+    /// If any of required values is not set, None is returned.
+    pub fn from_pool_config(pool_config: &crate::config::Pool) -> Option<Self> {
+        if pool_config.is_auth_query_configured() {
+            return Some(AuthPassthrough::new(
+                pool_config.auth_query.as_ref().unwrap(),
+                pool_config.auth_query_user.as_ref().unwrap(),
+                pool_config.auth_query_password.as_ref().unwrap(),
+            ));
+        }
+
+        None
+    }
+
+    /// Returns an AuthPassthrough given the pool settings.
+    /// If any of required values is not set, None is returned.
+    pub fn from_pool_settings(pool_settings: &crate::pool::PoolSettings) -> Option<Self> {
+        let pool_config = crate::config::Pool {
+            auth_query: pool_settings.auth_query.clone(),
+            auth_query_password: pool_settings.auth_query_password.clone(),
+            auth_query_user: pool_settings.auth_query_user.clone(),
+            ..Default::default()
+        };
+
+        AuthPassthrough::from_pool_config(&pool_config)
+    }
+
+    /// Connects to server and executes auth_query for the specified address.
+    /// If the response is a row with two columns containing the username set in the address.
+    /// and its MD5 hash, the MD5 hash returned.
+    ///
+    /// Note that the query is executed, changing $1 with the name of the user
+    /// this is so we only hold in memory (and transfer) the least amount of 'sensitive' data.
+    /// Also, it is compatible with pgbouncer.
+    ///
+    /// # Arguments
+    ///
+    /// * `address` - An Address of the server we want to connect to. The username for the hash will be obtained from this value.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use pgcat::auth_passthrough::AuthPassthrough;
+    /// use pgcat::config::Address;
+    /// let auth_passthrough = AuthPassthrough::new("SELECT * FROM public.user_lookup('$1');", "postgres", "postgres");
+    /// auth_passthrough.fetch_hash(&Address::default());
+    /// ```
+    ///
+    pub async fn fetch_hash(&self, address: &crate::config::Address) -> Result<String, Error> {
+        let auth_user = crate::config::User {
+            username: self.user.clone(),
+            password: Some(self.password.clone()),
+            server_username: None,
+            server_password: None,
+            pool_size: 1,
+            statement_timeout: 0,
+            pool_mode: None,
+            server_lifetime: None,
+            min_pool_size: None,
+        };
+
+        let user = &address.username;
+
+        debug!("Connecting to server to obtain auth hashes");
+
+        let auth_query = self.query.replace("$1", user);
+
+        match Server::exec_simple_query(address, &auth_user, &auth_query).await {
+            Ok(password_data) => {
+                if password_data.len() == 2 && password_data.first().unwrap() == user {
+                    if let Some(stripped_hash) = password_data
+                        .last()
+                        .unwrap()
+                        .to_string()
+                        .strip_prefix("md5") {
+                            Ok(stripped_hash.to_string())
+                        }
+                    else {
+                        Err(Error::AuthPassthroughError(
+                            "Obtained hash from auth_query does not seem to be in md5 format.".to_string(),
+                        ))
+                    }
+                } else {
+                    Err(Error::AuthPassthroughError(
+                        "Data obtained from query does not follow the scheme 'user','hash'."
+                            .to_string(),
+                    ))
+                 }
+            }
+            Err(err) => {
+                Err(Error::AuthPassthroughError(
+                    format!("Error trying to obtain password from auth_query, ignoring hash for user '{}'. Error: {:?}",
+                        user, err))
+                )
+            }
+        }
+    }
+}
+
+pub async fn refetch_auth_hash(pool: &ConnectionPool) -> Result<String, Error> {
+    let address = pool.address(0, 0);
+    if let Some(apt) = AuthPassthrough::from_pool_settings(&pool.settings) {
+        let hash = apt.fetch_hash(address).await?;
+
+        return Ok(hash);
+    }
+
+    Err(Error::ClientError(format!(
+        "Could not obtain hash for {{ username: {:?}, database: {:?} }}. Auth passthrough not enabled.",
+        address.username, address.database
+    )))
+}

src/client.rs

@@ -1,10 +1,10 @@
-use crate::errors::Error;
+use crate::errors::{ClientIdentifier, Error};
 use crate::pool::BanReason;
 /// Handle clients by pretending to be a PostgreSQL server.
 use bytes::{Buf, BufMut, BytesMut};
 use log::{debug, error, info, trace, warn};
-
 use std::collections::HashMap;
+use std::sync::Arc;
 use std::time::Instant;
 use tokio::io::{split, AsyncReadExt, BufReader, ReadHalf, WriteHalf};
 use tokio::net::TcpStream;
@@ -12,14 +12,14 @@ use tokio::sync::broadcast::Receiver;
 use tokio::sync::mpsc::Sender;
 
 use crate::admin::{generate_server_info_for_admin, handle_admin};
+use crate::auth_passthrough::refetch_auth_hash;
 use crate::config::{get_config, get_idle_client_in_transaction_timeout, Address, PoolMode};
 use crate::constants::*;
-
 use crate::messages::*;
 use crate::pool::{get_pool, ClientServerMap, ConnectionPool};
 use crate::query_router::{Command, QueryRouter};
 use crate::server::Server;
-use crate::stats::{get_reporter, Reporter};
+use crate::stats::{ClientStats, PoolStats, ServerStats};
 use crate::tls::Tls;
 
 use tokio_rustls::server::TlsStream;
@@ -66,8 +66,8 @@ pub struct Client<S, T> {
     #[allow(dead_code)]
     parameters: HashMap<String, String>,
 
-    /// Statistics
-    stats: Reporter,
+    /// Statistics related to this client
+    stats: Arc<ClientStats>,
 
     /// Clients want to talk to admin database.
     admin: bool,
@@ -75,8 +75,8 @@ pub struct Client<S, T> {
     /// Last address the client talked to.
     last_address_id: Option<usize>,
 
-    /// Last server process id we talked to.
-    last_server_id: Option<i32>,
+    /// Last server process stats we talked to.
+    last_server_stats: Option<Arc<ServerStats>>,
 
     /// Connected to server
     connected_to_server: bool,
@@ -135,6 +135,10 @@ pub async fn client_entrypoint(
 
                         if !client.is_admin() {
                             let _ = drain.send(-1).await;
+
+                            if result.is_err() {
+                                client.stats.disconnect();
+                            }
                         }
 
                         result
@@ -183,6 +187,10 @@ pub async fn client_entrypoint(
 
                                 if !client.is_admin() {
                                     let _ = drain.send(-1).await;
+
+                                    if result.is_err() {
+                                        client.stats.disconnect();
+                                    }
                                 }
 
                                 result
@@ -194,7 +202,7 @@ pub async fn client_entrypoint(
                     // Client probably disconnected rejecting our plain text connection.
                     Ok((ClientConnectionType::Tls, _))
                     | Ok((ClientConnectionType::CancelQuery, _)) => Err(Error::ProtocolSyncError(
-                        format!("Bad postgres client (plain)"),
+                        "Bad postgres client (plain)".into(),
                     )),
 
                     Err(err) => Err(err),
@@ -233,6 +241,10 @@ pub async fn client_entrypoint(
 
                     if !client.is_admin() {
                         let _ = drain.send(-1).await;
+
+                        if result.is_err() {
+                            client.stats.disconnect();
+                        }
                     }
 
                     result
@@ -258,8 +270,11 @@ pub async fn client_entrypoint(
 
                     if !client.is_admin() {
                         let _ = drain.send(-1).await;
-                    }
 
+                        if result.is_err() {
+                            client.stats.disconnect();
+                        }
+                    }
                     result
                 }
 
@@ -354,9 +369,9 @@ pub async fn startup_tls(
         }
 
         // Bad Postgres client.
-        Ok((ClientConnectionType::Tls, _)) | Ok((ClientConnectionType::CancelQuery, _)) => Err(
-            Error::ProtocolSyncError(format!("Bad postgres client (tls)")),
-        ),
+        Ok((ClientConnectionType::Tls, _)) | Ok((ClientConnectionType::CancelQuery, _)) => {
+            Err(Error::ProtocolSyncError("Bad postgres client (tls)".into()))
+        }
 
         Err(err) => Err(err),
     }
@@ -382,7 +397,6 @@ where
         shutdown: Receiver<()>,
         admin_only: bool,
     ) -> Result<Client<S, T>, Error> {
-        let stats = get_reporter();
         let parameters = parse_startup(bytes.clone())?;
 
         // This parameter is mandatory by the protocol.
@@ -390,7 +404,7 @@ where
             Some(user) => user,
             None => {
                 return Err(Error::ClientError(
-                    "Missing user parameter on client startup".to_string(),
+                    "Missing user parameter on client startup".into(),
                 ))
             }
         };
@@ -405,6 +419,8 @@ where
             None => "pgcat",
         };
 
+        let client_identifier = ClientIdentifier::new(&application_name, &username, &pool_name);
+
         let admin = ["pgcat", "pgbouncer"]
             .iter()
             .filter(|db| *db == pool_name)
@@ -435,7 +451,12 @@ where
 
         let code = match read.read_u8().await {
             Ok(p) => p,
-            Err(_) => return Err(Error::SocketError(format!("Error reading password code from client {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name))),
+            Err(_) => {
+                return Err(Error::ClientSocketError(
+                    "password code".into(),
+                    client_identifier,
+                ))
+            }
         };
 
         // PasswordMessage
@@ -448,19 +469,30 @@ where
 
         let len = match read.read_i32().await {
             Ok(len) => len,
-            Err(_) => return Err(Error::SocketError(format!("Error reading password message length from client {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name))),
+            Err(_) => {
+                return Err(Error::ClientSocketError(
+                    "password message length".into(),
+                    client_identifier,
+                ))
+            }
         };
 
         let mut password_response = vec![0u8; (len - 4) as usize];
 
         match read.read_exact(&mut password_response).await {
             Ok(_) => (),
-            Err(_) => return Err(Error::SocketError(format!("Error reading password message from client {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name))),
+            Err(_) => {
+                return Err(Error::ClientSocketError(
+                    "password message".into(),
+                    client_identifier,
+                ))
+            }
         };
 
         // Authenticate admin user.
         let (transaction_mode, server_info) = if admin {
             let config = get_config();
+
             // Compare server and client hashes.
             let password_hash = md5_hash_password(
                 &config.general.admin_username,
@@ -469,10 +501,12 @@ where
             );
 
             if password_hash != password_response {
-                warn!("Invalid password {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name);
+                let error = Error::ClientGeneralError("Invalid password".into(), client_identifier);
+
+                warn!("{}", error);
                 wrong_password(&mut write, username).await?;
 
-                return Err(Error::ClientError(format!("Invalid password {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name)));
+                return Err(error);
             }
 
             (false, generate_server_info_for_admin())
@@ -491,18 +525,100 @@ where
                     )
                     .await?;
 
-                    return Err(Error::ClientError(format!("Invalid pool name {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name)));
+                    return Err(Error::ClientGeneralError(
+                        "Invalid pool name".into(),
+                        client_identifier,
+                    ));
                 }
             };
 
-            // Compare server and client hashes.
-            let password_hash = md5_hash_password(username, &pool.settings.user.password, &salt);
+            // Obtain the hash to compare, we give preference to that written in cleartext in config
+            // if there is nothing set in cleartext and auth passthrough (auth_query) is configured, we use the hash obtained
+            // when the pool was created. If there is no hash there, we try to fetch it one more time.
+            let password_hash = if let Some(password) = &pool.settings.user.password {
+                Some(md5_hash_password(username, password, &salt))
+            } else {
+                if !get_config().is_auth_query_configured() {
+                    wrong_password(&mut write, username).await?;
+                    return Err(Error::ClientAuthImpossible(username.into()));
+                }
 
-            if password_hash != password_response {
-                warn!("Invalid password {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name);
-                wrong_password(&mut write, username).await?;
+                let mut hash = (*pool.auth_hash.read()).clone();
 
-                return Err(Error::ClientError(format!("Invalid password {{ username: {:?}, pool_name: {:?}, application_name: {:?} }}", username, pool_name, application_name)));
+                if hash.is_none() {
+                    warn!(
+                        "Query auth configured \
+                          but no hash password found \
+                          for pool {}. Will try to refetch it.",
+                        pool_name
+                    );
+
+                    match refetch_auth_hash(&pool).await {
+                        Ok(fetched_hash) => {
+                            warn!("Password for {}, obtained. Updating.", client_identifier);
+
+                            {
+                                let mut pool_auth_hash = pool.auth_hash.write();
+                                *pool_auth_hash = Some(fetched_hash.clone());
+                            }
+
+                            hash = Some(fetched_hash);
+                        }
+
+                        Err(err) => {
+                            wrong_password(&mut write, username).await?;
+
+                            return Err(Error::ClientAuthPassthroughError(
+                                err.to_string(),
+                                client_identifier,
+                            ));
+                        }
+                    }
+                };
+
+                Some(md5_hash_second_pass(&hash.unwrap(), &salt))
+            };
+
+            // Once we have the resulting hash, we compare with what the client gave us.
+            // If they do not match and auth query is set up, we try to refetch the hash one more time
+            // to see if the password has changed since the pool was created.
+            //
+            // @TODO: we could end up fetching again the same password twice (see above).
+            if password_hash.unwrap() != password_response {
+                warn!(
+                    "Invalid password {}, will try to refetch it.",
+                    client_identifier
+                );
+
+                let fetched_hash = match refetch_auth_hash(&pool).await {
+                    Ok(fetched_hash) => fetched_hash,
+                    Err(err) => {
+                        wrong_password(&mut write, username).await?;
+
+                        return Err(err);
+                    }
+                };
+
+                let new_password_hash = md5_hash_second_pass(&fetched_hash, &salt);
+
+                // Ok password changed in server an auth is possible.
+                if new_password_hash == password_response {
+                    warn!(
+                        "Password for {}, changed in server. Updating.",
+                        client_identifier
+                    );
+
+                    {
+                        let mut pool_auth_hash = pool.auth_hash.write();
+                        *pool_auth_hash = Some(fetched_hash);
+                    }
+                } else {
+                    wrong_password(&mut write, username).await?;
+                    return Err(Error::ClientGeneralError(
+                        "Invalid password".into(),
+                        client_identifier,
+                    ));
+                }
             }
 
             let transaction_mode = pool.settings.pool_mode == PoolMode::Transaction;
@@ -537,6 +653,25 @@ where
         ready_for_query(&mut write).await?;
 
         trace!("Startup OK");
+        let pool_stats = match get_pool(pool_name, username) {
+            Some(pool) => {
+                if !admin {
+                    pool.stats
+                } else {
+                    Arc::new(PoolStats::default())
+                }
+            }
+            None => Arc::new(PoolStats::default()),
+        };
+
+        let stats = Arc::new(ClientStats::new(
+            process_id,
+            application_name,
+            username,
+            pool_name,
+            tokio::time::Instant::now(),
+            pool_stats,
+        ));
 
         Ok(Client {
             read: BufReader::new(read),
@@ -552,7 +687,7 @@ where
             stats,
             admin,
             last_address_id: None,
-            last_server_id: None,
+            last_server_stats: None,
             pool_name: pool_name.clone(),
             username: username.clone(),
             application_name: application_name.to_string(),
@@ -583,10 +718,10 @@ where
             secret_key,
             client_server_map,
             parameters: HashMap::new(),
-            stats: get_reporter(),
+            stats: Arc::new(ClientStats::default()),
             admin: false,
             last_address_id: None,
-            last_server_id: None,
+            last_server_stats: None,
             pool_name: String::from("undefined"),
             username: String::from("undefined"),
             application_name: String::from("undefined"),
@@ -627,12 +762,8 @@ where
         // The query router determines where the query is going to go,
         // e.g. primary, replica, which shard.
         let mut query_router = QueryRouter::new();
-        self.stats.client_register(
-            self.process_id,
-            self.pool_name.clone(),
-            self.username.clone(),
-            self.application_name.clone(),
-        );
+
+        self.stats.register(self.stats.clone());
 
         // Our custom protocol loop.
         // We expect the client to either start a transaction with regular queries
@@ -656,7 +787,9 @@ where
                             &mut self.write,
                             "terminating connection due to administrator command"
                         ).await?;
-                        return Ok(())
+
+                        self.stats.disconnect();
+                        return Ok(());
                     }
 
                     // Admin clients ignore shutdown.
@@ -708,6 +841,9 @@ where
 
                 'X' => {
                     debug!("Client disconnecting");
+
+                    self.stats.disconnect();
+
                     return Ok(());
                 }
 
@@ -757,7 +893,7 @@ where
                                 current_shard,
                             ),
                         )
-                        .await?;
+                            .await?;
                     } else {
                         custom_protocol_response_ok(&mut self.write, "SET SHARD").await?;
                     }
@@ -802,10 +938,13 @@ where
             };
 
             debug!("Waiting for connection from pool");
+            if !self.admin {
+                self.stats.waiting();
+            }
 
             // Grab a server from the pool.
             let connection = match pool
-                .get(query_router.shard(), query_router.role(), self.process_id)
+                .get(query_router.shard(), query_router.role(), &self.stats)
                 .await
             {
                 Ok(conn) => {
@@ -817,15 +956,32 @@ where
                     // but we were unable to grab a connection from the pool
                     // We'll send back an error message and clean the extended
                     // protocol buffer
+                    self.stats.idle();
+
                     if message[0] as char == 'S' {
                         error!("Got Sync message but failed to get a connection from the pool");
                         self.buffer.clear();
                     }
+
                     error_response(&mut self.write, "could not get connection from the pool")
                         .await?;
 
-                    error!("Could not get connection from pool: {{ pool_name: {:?}, username: {:?}, shard: {:?}, role: \"{:?}\", error: \"{:?}\" }}",
-                    self.pool_name.clone(), self.username.clone(), query_router.shard(), query_router.role(), err);
+                    error!(
+                        "Could not get connection from pool: \
+                        {{ \
+                            pool_name: {:?}, \
+                            username: {:?}, \
+                            shard: {:?}, \
+                            role: \"{:?}\", \
+                            error: \"{:?}\" \
+                        }}",
+                        self.pool_name,
+                        self.username,
+                        query_router.shard(),
+                        query_router.role(),
+                        err
+                    );
+
                     continue;
                 }
             };
@@ -840,11 +996,10 @@ where
             self.connected_to_server = true;
 
             // Update statistics
-            self.stats
-                .client_active(self.process_id, server.server_id());
+            self.stats.active();
 
             self.last_address_id = Some(address.id);
-            self.last_server_id = Some(server.server_id());
+            self.last_server_stats = Some(server.stats());
 
             debug!(
                 "Client {:?} talking to server {:?}",
@@ -885,6 +1040,7 @@ where
                             Ok(Err(err)) => {
                                 // Client disconnected inside a transaction.
                                 // Clean up the server and re-use it.
+                                self.stats.disconnect();
                                 server.checkin_cleanup().await?;
 
                                 return Err(err);
@@ -892,11 +1048,25 @@ where
                             Err(_) => {
                                 // Client idle in transaction timeout
                                 error_response(&mut self.write, "idle transaction timeout").await?;
-                                error!("Client idle in transaction timeout: {{ pool_name: {:?}, username: {:?}, shard: {:?}, role: \"{:?}\"}}", self.pool_name.clone(), self.username.clone(), query_router.shard(), query_router.role());
+                                error!(
+                                    "Client idle in transaction timeout: \
+                                    {{ \
+                                        pool_name: {}, \
+                                        username: {}, \
+                                        shard: {}, \
+                                        role: \"{:?}\" \
+                                    }}",
+                                    self.pool_name,
+                                    self.username,
+                                    query_router.shard(),
+                                    query_router.role()
+                                );
+
                                 break;
                             }
                         }
                     }
+
                     Some(message) => {
                         initial_message = None;
                         message
@@ -917,16 +1087,26 @@ where
                     'Q' => {
                         debug!("Sending query to server");
 
-                        self.send_and_receive_loop(code, Some(&message), server, &address, &pool)
-                            .await?;
+                        self.send_and_receive_loop(
+                            code,
+                            Some(&message),
+                            server,
+                            &address,
+                            &pool,
+                            &self.stats.clone(),
+                        )
+                        .await?;
 
                         if !server.in_transaction() {
                             // Report transaction executed statistics.
-                            self.stats.transaction(self.process_id, server.server_id());
+                            self.stats.transaction();
+                            server.stats().transaction(&self.application_name);
 
                             // Release server back to the pool if we are in transaction mode.
                             // If we are in session mode, we keep the server until the client disconnects.
                             if self.transaction_mode {
+                                self.stats.idle();
+
                                 break;
                             }
                         }
@@ -935,6 +1115,7 @@ where
                     // Terminate
                     'X' => {
                         server.checkin_cleanup().await?;
+                        self.stats.disconnect();
                         self.release();
 
                         return Ok(());
@@ -958,6 +1139,11 @@ where
                         self.buffer.put(&message[..]);
                     }
 
+                    // Close the prepared statement.
+                    'C' => {
+                        self.buffer.put(&message[..]);
+                    }
+
                     // Execute
                     // Execute a prepared statement prepared in `P` and bound in `B`.
                     'E' => {
@@ -987,13 +1173,21 @@ where
                             }
                         }
 
-                        self.send_and_receive_loop(code, None, server, &address, &pool)
-                            .await?;
+                        self.send_and_receive_loop(
+                            code,
+                            None,
+                            server,
+                            &address,
+                            &pool,
+                            &self.stats.clone(),
+                        )
+                        .await?;
 
                         self.buffer.clear();
 
                         if !server.in_transaction() {
-                            self.stats.transaction(self.process_id, server.server_id());
+                            self.stats.transaction();
+                            server.stats().transaction(&self.application_name);
 
                             // Release server back to the pool if we are in transaction mode.
                             // If we are in session mode, we keep the server until the client disconnects.
@@ -1028,7 +1222,9 @@ where
                         // Clear the buffer
                         self.buffer.clear();
 
-                        let response = self.receive_server_message(server, &address, &pool).await?;
+                        let response = self
+                            .receive_server_message(server, &address, &pool, &self.stats.clone())
+                            .await?;
 
                         match write_all_half(&mut self.write, &response).await {
                             Ok(_) => (),
@@ -1039,7 +1235,8 @@ where
                         };
 
                         if !server.in_transaction() {
-                            self.stats.transaction(self.process_id, server.server_id());
+                            self.stats.transaction();
+                            server.stats().transaction(&self.application_name);
 
                             // Release server back to the pool if we are in transaction mode.
                             // If we are in session mode, we keep the server until the client disconnects.
@@ -1060,11 +1257,11 @@ where
             // The server is no longer bound to us, we can't cancel it's queries anymore.
             debug!("Releasing server back into the pool");
             server.checkin_cleanup().await?;
-            self.stats.server_idle(server.server_id());
+            server.stats().idle();
             self.connected_to_server = false;
 
             self.release();
-            self.stats.client_idle(self.process_id);
+            self.stats.idle();
         }
     }
 
@@ -1104,6 +1301,7 @@ where
         server: &mut Server,
         address: &Address,
         pool: &ConnectionPool,
+        client_stats: &ClientStats,
     ) -> Result<(), Error> {
         debug!("Sending {} to server", code);
 
@@ -1119,7 +1317,9 @@ where
         // Read all data the server has to offer, which can be multiple messages
         // buffered in 8196 bytes chunks.
         loop {
-            let response = self.receive_server_message(server, address, pool).await?;
+            let response = self
+                .receive_server_message(server, address, pool, client_stats)
+                .await?;
 
             match write_all_half(&mut self.write, &response).await {
                 Ok(_) => (),
@@ -1135,10 +1335,10 @@ where
         }
 
         // Report query executed statistics.
-        self.stats.query(
-            self.process_id,
-            server.server_id(),
-            Instant::now().duration_since(query_start).as_millis(),
+        client_stats.query();
+        server.stats().query(
+            Instant::now().duration_since(query_start).as_millis() as u64,
+            &self.application_name,
         );
 
         Ok(())
@@ -1154,7 +1354,7 @@ where
         match server.send(message).await {
             Ok(_) => Ok(()),
             Err(err) => {
-                pool.ban(address, BanReason::MessageSendFailed, self.process_id);
+                pool.ban(address, BanReason::MessageSendFailed, Some(&self.stats));
                 Err(err)
             }
         }
@@ -1165,6 +1365,7 @@ where
         server: &mut Server,
         address: &Address,
         pool: &ConnectionPool,
+        client_stats: &ClientStats,
     ) -> Result<BytesMut, Error> {
         if pool.settings.user.statement_timeout > 0 {
             match tokio::time::timeout(
@@ -1176,7 +1377,7 @@ where
                 Ok(result) => match result {
                     Ok(message) => Ok(message),
                     Err(err) => {
-                        pool.ban(address, BanReason::MessageReceiveFailed, self.process_id);
+                        pool.ban(address, BanReason::MessageReceiveFailed, Some(client_stats));
                         error_response_terminal(
                             &mut self.write,
                             &format!("error receiving data from server: {:?}", err),
@@ -1191,7 +1392,7 @@ where
                         address, pool.settings.user.username
                     );
                     server.mark_bad();
-                    pool.ban(address, BanReason::StatementTimeout, self.process_id);
+                    pool.ban(address, BanReason::StatementTimeout, Some(client_stats));
                     error_response_terminal(&mut self.write, "pool statement timeout").await?;
                     Err(Error::StatementTimeout)
                 }
@@ -1200,7 +1401,7 @@ where
             match server.recv().await {
                 Ok(message) => Ok(message),
                 Err(err) => {
-                    pool.ban(address, BanReason::MessageReceiveFailed, self.process_id);
+                    pool.ban(address, BanReason::MessageReceiveFailed, Some(client_stats));
                     error_response_terminal(
                         &mut self.write,
                         &format!("error receiving data from server: {:?}", err),
@@ -1220,9 +1421,9 @@ impl<S, T> Drop for Client<S, T> {
 
         // Dirty shutdown
         // TODO: refactor, this is not the best way to handle state management.
-        self.stats.client_disconnecting(self.process_id);
-        if self.connected_to_server && self.last_server_id.is_some() {
-            self.stats.server_idle(self.last_server_id.unwrap());
+
+        if self.connected_to_server && self.last_server_stats.is_some() {
+            self.last_server_stats.as_ref().unwrap().idle();
         }
     }
 }

src/config.rs

@@ -15,6 +15,7 @@ use tokio::io::AsyncReadExt;
 use crate::errors::Error;
 use crate::pool::{ClientServerMap, ConnectionPool};
 use crate::sharding::ShardingFunction;
+use crate::stats::AddressStats;
 use crate::tls::{load_certs, load_keys};
 
 pub const VERSION: &str = env!("CARGO_PKG_VERSION");
@@ -62,7 +63,7 @@ impl PartialEq<Role> for Option<Role> {
 }
 
 /// Address identifying a PostgreSQL server uniquely.
-#[derive(Clone, PartialEq, Hash, std::cmp::Eq, Debug)]
+#[derive(Clone, Debug)]
 pub struct Address {
     /// Unique ID per addressable Postgres server.
     pub id: usize,
@@ -96,6 +97,9 @@ pub struct Address {
 
     /// List of addresses to receive mirrored traffic.
     pub mirrors: Vec<Address>,
+
+    /// Address stats
+    pub stats: Arc<AddressStats>,
 }
 
 impl Default for Address {
@@ -112,10 +116,46 @@ impl Default for Address {
             username: String::from("username"),
             pool_name: String::from("pool_name"),
             mirrors: Vec::new(),
+            stats: Arc::new(AddressStats::default()),
         }
     }
 }
 
+// We need to implement PartialEq by ourselves so we skip stats in the comparison
+impl PartialEq for Address {
+    fn eq(&self, other: &Self) -> bool {
+        self.id == other.id
+            && self.host == other.host
+            && self.port == other.port
+            && self.shard == other.shard
+            && self.address_index == other.address_index
+            && self.replica_number == other.replica_number
+            && self.database == other.database
+            && self.role == other.role
+            && self.username == other.username
+            && self.pool_name == other.pool_name
+            && self.mirrors == other.mirrors
+    }
+}
+impl Eq for Address {}
+
+// We need to implement Hash by ourselves so we skip stats in the comparison
+impl Hash for Address {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.id.hash(state);
+        self.host.hash(state);
+        self.port.hash(state);
+        self.shard.hash(state);
+        self.address_index.hash(state);
+        self.replica_number.hash(state);
+        self.database.hash(state);
+        self.role.hash(state);
+        self.username.hash(state);
+        self.pool_name.hash(state);
+        self.mirrors.hash(state);
+    }
+}
+
 impl Address {
     /// Address name (aka database) used in `SHOW STATS`, `SHOW DATABASES`, and `SHOW POOLS`.
     pub fn name(&self) -> String {
@@ -137,8 +177,13 @@ impl Address {
 #[derive(Clone, PartialEq, Hash, Eq, Serialize, Deserialize, Debug)]
 pub struct User {
     pub username: String,
-    pub password: String,
+    pub password: Option<String>,
+    pub server_username: Option<String>,
+    pub server_password: Option<String>,
     pub pool_size: u32,
+    pub min_pool_size: Option<u32>,
+    pub pool_mode: Option<PoolMode>,
+    pub server_lifetime: Option<u64>,
     #[serde(default)] // 0
     pub statement_timeout: u64,
 }
@@ -147,13 +192,38 @@ impl Default for User {
     fn default() -> User {
         User {
             username: String::from("postgres"),
-            password: String::new(),
+            password: None,
+            server_username: None,
+            server_password: None,
             pool_size: 15,
+            min_pool_size: None,
             statement_timeout: 0,
+            pool_mode: None,
+            server_lifetime: None,
         }
     }
 }
 
+impl User {
+    fn validate(&self) -> Result<(), Error> {
+        match self.min_pool_size {
+            Some(min_pool_size) => {
+                if min_pool_size > self.pool_size {
+                    error!(
+                        "min_pool_size of {} cannot be larger than pool_size of {}",
+                        min_pool_size, self.pool_size
+                    );
+                    return Err(Error::BadConfig);
+                }
+            }
+
+            None => (),
+        };
+
+        Ok(())
+    }
+}
+
 /// General configuration.
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
 pub struct General {
@@ -161,7 +231,7 @@ pub struct General {
     pub host: String,
 
     #[serde(default = "General::default_port")]
-    pub port: i16,
+    pub port: u16,
 
     pub enable_prometheus_exporter: Option<bool>,
     pub prometheus_exporter_port: i16,
@@ -200,16 +270,30 @@ pub struct General {
     #[serde(default = "General::default_idle_client_in_transaction_timeout")]
     pub idle_client_in_transaction_timeout: u64,
 
+    #[serde(default = "General::default_server_lifetime")]
+    pub server_lifetime: u64,
+
     #[serde(default = "General::default_worker_threads")]
     pub worker_threads: usize,
 
-    #[serde(default)] // False
-    pub autoreload: bool,
+    #[serde(default)] // None
+    pub autoreload: Option<u64>,
 
     pub tls_certificate: Option<String>,
     pub tls_private_key: Option<String>,
+
+    #[serde(default)] // false
+    pub server_tls: bool,
+
+    #[serde(default)] // false
+    pub verify_server_certificate: bool,
+
     pub admin_username: String,
     pub admin_password: String,
+
+    pub auth_query: Option<String>,
+    pub auth_query_user: Option<String>,
+    pub auth_query_password: Option<String>,
 }
 
 impl General {
@@ -217,17 +301,21 @@ impl General {
         "0.0.0.0".into()
     }
 
-    pub fn default_port() -> i16 {
+    pub fn default_port() -> u16 {
         5432
     }
 
+    pub fn default_server_lifetime() -> u64 {
+        1000 * 60 * 60 * 24 // 24 hours
+    }
+
     pub fn default_connect_timeout() -> u64 {
         1000
     }
 
     // These keepalive defaults should detect a dead connection within 30 seconds.
     // Tokio defaults to disabling keepalives which keeps dead connections around indefinitely.
-    // This can lead to permenant server pool exhaustion
+    // This can lead to permanent server pool exhaustion
     pub fn default_tcp_keepalives_idle() -> u64 {
         5 // 5 seconds
     }
@@ -289,11 +377,17 @@ impl Default for General {
             tcp_keepalives_interval: Self::default_tcp_keepalives_interval(),
             log_client_connections: false,
             log_client_disconnections: false,
-            autoreload: false,
+            autoreload: None,
             tls_certificate: None,
             tls_private_key: None,
+            server_tls: false,
+            verify_server_certificate: false,
             admin_username: String::from("admin"),
             admin_password: String::from("admin"),
+            auth_query: None,
+            auth_query_user: None,
+            auth_query_password: None,
+            server_lifetime: 1000 * 3600 * 24, // 24 hours,
         }
     }
 }
@@ -309,6 +403,7 @@ pub enum PoolMode {
     #[serde(alias = "session", alias = "Session")]
     Session,
 }
+
 impl ToString for PoolMode {
     fn to_string(&self) -> String {
         match *self {
@@ -357,6 +452,8 @@ pub struct Pool {
 
     pub idle_timeout: Option<u64>,
 
+    pub server_lifetime: Option<u64>,
+
     pub sharding_function: ShardingFunction,
 
     #[serde(default = "Pool::default_automatic_sharding_key")]
@@ -366,9 +463,13 @@ pub struct Pool {
     pub shard_id_regex: Option<String>,
     pub regex_search_limit: Option<usize>,
 
+    pub auth_query: Option<String>,
+    pub auth_query_user: Option<String>,
+    pub auth_query_password: Option<String>,
+
     pub shards: BTreeMap<String, Shard>,
     pub users: BTreeMap<String, User>,
-    // Note, don't put simple fields below these configs. There's a compatability issue with TOML that makes it
+    // Note, don't put simple fields below these configs. There's a compatibility issue with TOML that makes it
     // incompatible to have simple fields in TOML after complex objects. See
     // https://users.rust-lang.org/t/why-toml-to-string-get-error-valueaftertable/85903
 }
@@ -380,6 +481,12 @@ impl Pool {
         s.finish()
     }
 
+    pub fn is_auth_query_configured(&self) -> bool {
+        self.auth_query_password.is_some()
+            && self.auth_query_user.is_some()
+            && self.auth_query_password.is_some()
+    }
+
     pub fn default_pool_mode() -> PoolMode {
         PoolMode::Transaction
     }
@@ -451,6 +558,10 @@ impl Pool {
             None => None,
         };
 
+        for (_, user) in &self.users {
+            user.validate()?;
+        }
+
         Ok(())
     }
 }
@@ -472,6 +583,10 @@ impl Default for Pool {
             sharding_key_regex: None,
             shard_id_regex: None,
             regex_search_limit: Some(1000),
+            auth_query: None,
+            auth_query_user: None,
+            auth_query_password: None,
+            server_lifetime: None,
         }
     }
 }
@@ -521,7 +636,7 @@ impl Shard {
 
         if primary_count > 1 {
             error!(
-                "Shard {} has more than on primary configured",
+                "Shard {} has more than one primary configured",
                 self.database
             );
             return Err(Error::BadConfig);
@@ -572,9 +687,31 @@ pub struct Config {
 }
 
 impl Config {
+    pub fn is_auth_query_configured(&self) -> bool {
+        self.pools
+            .iter()
+            .any(|(_name, pool)| pool.is_auth_query_configured())
+    }
+
     pub fn default_path() -> String {
         String::from("pgcat.toml")
     }
+
+    pub fn fill_up_auth_query_config(&mut self) {
+        for (_name, pool) in self.pools.iter_mut() {
+            if pool.auth_query.is_none() {
+                pool.auth_query = self.general.auth_query.clone();
+            }
+
+            if pool.auth_query_user.is_none() {
+                pool.auth_query_user = self.general.auth_query_user.clone();
+            }
+
+            if pool.auth_query_password.is_none() {
+                pool.auth_query_password = self.general.auth_query_password.clone();
+            }
+        }
+    }
 }
 
 impl Default for Config {
@@ -702,6 +839,10 @@ impl Config {
         );
         info!("Shutdown timeout: {}ms", self.general.shutdown_timeout);
         info!("Healthcheck delay: {}ms", self.general.healthcheck_delay);
+        info!(
+            "Default max server lifetime: {}ms",
+            self.general.server_lifetime
+        );
         match self.general.tls_certificate.clone() {
             Some(tls_certificate) => {
                 info!("TLS certificate: {}", tls_certificate);
@@ -720,6 +861,11 @@ impl Config {
                 info!("TLS support is disabled");
             }
         };
+        info!("Server TLS enabled: {}", self.general.server_tls);
+        info!(
+            "Server TLS certificate verification: {}",
+            self.general.verify_server_certificate
+        );
 
         for (pool_name, pool_config) in &self.pools {
             // TODO: Make this output prettier (maybe a table?)
@@ -734,8 +880,9 @@ impl Config {
                     .to_string()
             );
             info!(
-                "[pool: {}] Pool mode: {:?}",
-                pool_name, pool_config.pool_mode
+                "[pool: {}] Default pool mode: {}",
+                pool_name,
+                pool_config.pool_mode.to_string()
             );
             info!(
                 "[pool: {}] Load Balancing mode: {:?}",
@@ -777,21 +924,101 @@ impl Config {
                 pool_name,
                 pool_config.users.len()
             );
+            info!(
+                "[pool: {}] Max server lifetime: {}",
+                pool_name,
+                match pool_config.server_lifetime {
+                    Some(server_lifetime) => format!("{}ms", server_lifetime),
+                    None => "default".to_string(),
+                }
+            );
 
             for user in &pool_config.users {
                 info!(
                     "[pool: {}][user: {}] Pool size: {}",
                     pool_name, user.1.username, user.1.pool_size,
                 );
+                info!(
+                    "[pool: {}][user: {}] Minimum pool size: {}",
+                    pool_name,
+                    user.1.username,
+                    user.1.min_pool_size.unwrap_or(0)
+                );
                 info!(
                     "[pool: {}][user: {}] Statement timeout: {}",
                     pool_name, user.1.username, user.1.statement_timeout
-                )
+                );
+                info!(
+                    "[pool: {}][user: {}] Pool mode: {}",
+                    pool_name,
+                    user.1.username,
+                    match user.1.pool_mode {
+                        Some(pool_mode) => pool_mode.to_string(),
+                        None => pool_config.pool_mode.to_string(),
+                    }
+                );
+                info!(
+                    "[pool: {}][user: {}] Max server lifetime: {}",
+                    pool_name,
+                    user.1.username,
+                    match user.1.server_lifetime {
+                        Some(server_lifetime) => format!("{}ms", server_lifetime),
+                        None => "default".to_string(),
+                    }
+                );
             }
         }
     }
 
     pub fn validate(&mut self) -> Result<(), Error> {
+        // Validation for auth_query feature
+        if self.general.auth_query.is_some()
+            && (self.general.auth_query_user.is_none()
+                || self.general.auth_query_password.is_none())
+        {
+            error!(
+                "If auth_query is specified, \
+                you need to provide a value \
+                for `auth_query_user`, \
+                `auth_query_password`"
+            );
+
+            return Err(Error::BadConfig);
+        }
+
+        for (name, pool) in self.pools.iter() {
+            if pool.auth_query.is_some()
+                && (pool.auth_query_user.is_none() || pool.auth_query_password.is_none())
+            {
+                error!(
+                    "Error in pool {{ {} }}. \
+                    If auth_query is specified, you need \
+                    to provide a value for `auth_query_user`, \
+                    `auth_query_password`",
+                    name
+                );
+
+                return Err(Error::BadConfig);
+            }
+
+            for (_name, user_data) in pool.users.iter() {
+                if (pool.auth_query.is_none()
+                    || pool.auth_query_password.is_none()
+                    || pool.auth_query_user.is_none())
+                    && user_data.password.is_none()
+                {
+                    error!(
+                        "Error in pool {{ {} }}. \
+                        You have to specify a user password \
+                        for every pool if auth_query is not specified",
+                        name
+                    );
+
+                    return Err(Error::BadConfig);
+                }
+            }
+        }
+
         // Validate TLS!
         match self.general.tls_certificate.clone() {
             Some(tls_certificate) => {
@@ -871,6 +1098,7 @@ pub async fn parse(path: &str) -> Result<(), Error> {
         }
     };
 
+    config.fill_up_auth_query_config();
     config.validate()?;
 
     config.path = path.to_string();
@@ -940,7 +1168,10 @@ mod test {
             "sharding_user"
         );
         assert_eq!(
-            get_config().pools["sharded_db"].users["1"].password,
+            get_config().pools["sharded_db"].users["1"]
+                .password
+                .as_ref()
+                .unwrap(),
             "other_user"
         );
         assert_eq!(get_config().pools["sharded_db"].users["1"].pool_size, 21);
@@ -965,10 +1196,16 @@ mod test {
             "simple_user"
         );
         assert_eq!(
-            get_config().pools["simple_db"].users["0"].password,
+            get_config().pools["simple_db"].users["0"]
+                .password
+                .as_ref()
+                .unwrap(),
             "simple_user"
         );
         assert_eq!(get_config().pools["simple_db"].users["0"].pool_size, 5);
+        assert_eq!(get_config().general.auth_query, None);
+        assert_eq!(get_config().general.auth_query_user, None);
+        assert_eq!(get_config().general.auth_query_password, None);
     }
 
     #[tokio::test]

src/errors.rs

@@ -1,13 +1,19 @@
-/// Errors.
+//! Errors.
 
 /// Various errors.
 #[derive(Debug, PartialEq)]
 pub enum Error {
     SocketError(String),
+    ClientSocketError(String, ClientIdentifier),
+    ClientGeneralError(String, ClientIdentifier),
+    ClientAuthImpossible(String),
+    ClientAuthPassthroughError(String, ClientIdentifier),
     ClientBadStartup,
     ProtocolSyncError(String),
     BadQuery(String),
     ServerError,
+    ServerStartupError(String, ServerIdentifier),
+    ServerAuthError(String, ServerIdentifier),
     BadConfig,
     AllServersDown,
     ClientError(String),
@@ -15,4 +21,100 @@ pub enum Error {
     StatementTimeout,
     ShuttingDown,
     ParseBytesError(String),
+    AuthError(String),
+    AuthPassthroughError(String),
+}
+
+#[derive(Clone, PartialEq, Debug)]
+pub struct ClientIdentifier {
+    pub application_name: String,
+    pub username: String,
+    pub pool_name: String,
+}
+
+impl ClientIdentifier {
+    pub fn new(application_name: &str, username: &str, pool_name: &str) -> ClientIdentifier {
+        ClientIdentifier {
+            application_name: application_name.into(),
+            username: username.into(),
+            pool_name: pool_name.into(),
+        }
+    }
+}
+
+impl std::fmt::Display for ClientIdentifier {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(
+            f,
+            "{{ application_name: {}, username: {}, pool_name: {} }}",
+            self.application_name, self.username, self.pool_name
+        )
+    }
+}
+
+#[derive(Clone, PartialEq, Debug)]
+pub struct ServerIdentifier {
+    pub username: String,
+    pub database: String,
+}
+
+impl ServerIdentifier {
+    pub fn new(username: &str, database: &str) -> ServerIdentifier {
+        ServerIdentifier {
+            username: username.into(),
+            database: database.into(),
+        }
+    }
+}
+
+impl std::fmt::Display for ServerIdentifier {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(
+            f,
+            "{{ username: {}, database: {} }}",
+            self.username, self.database
+        )
+    }
+}
+
+impl std::fmt::Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match &self {
+            &Error::ClientSocketError(error, client_identifier) => write!(
+                f,
+                "Error reading {} from client {}",
+                error, client_identifier
+            ),
+            &Error::ClientGeneralError(error, client_identifier) => {
+                write!(f, "{} {}", error, client_identifier)
+            }
+            &Error::ClientAuthImpossible(username) => write!(
+                f,
+                "Client auth not possible, \
+                no cleartext password set for username: {} \
+                in config and auth passthrough (query_auth) \
+                is not set up.",
+                username
+            ),
+            &Error::ClientAuthPassthroughError(error, client_identifier) => write!(
+                f,
+                "No cleartext password set, \
+                    and no auth passthrough could not \
+                    obtain the hash from server for {}, \
+                    the error was: {}",
+                client_identifier, error
+            ),
+            &Error::ServerStartupError(error, server_identifier) => write!(
+                f,
+                "Error reading {} on server startup {}",
+                error, server_identifier,
+            ),
+            &Error::ServerAuthError(error, server_identifier) => {
+                write!(f, "{} for {}", error, server_identifier,)
+            }
+
+            // The rest can use Debug.
+            err => write!(f, "{:?}", err),
+        }
+    }
 }

src/lib.rs

@@ -1,3 +1,4 @@
+pub mod auth_passthrough;
 pub mod config;
 pub mod constants;
 pub mod errors;

src/main.rs

@@ -61,6 +61,7 @@ use std::sync::Arc;
 use tokio::sync::broadcast;
 
 mod admin;
+mod auth_passthrough;
 mod client;
 mod config;
 mod constants;
@@ -78,6 +79,7 @@ mod stats;
 mod tls;
 
 use crate::config::{get_config, reload_config, VERSION};
+use crate::messages::configure_socket;
 use crate::pool::{ClientServerMap, ConnectionPool};
 use crate::prometheus::start_metric_server;
 use crate::stats::{Collector, Reporter, REPORTER};
@@ -162,8 +164,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         let client_server_map: ClientServerMap = Arc::new(Mutex::new(HashMap::new()));
 
         // Statistics reporting.
-        let (stats_tx, stats_rx) = mpsc::channel(500_000);
-        REPORTER.store(Arc::new(Reporter::new(stats_tx.clone())));
+        REPORTER.store(Arc::new(Reporter::default()));
 
         // Connection pool that allows to query all shards and replicas.
         match ConnectionPool::from_config(client_server_map.clone()).await {
@@ -175,20 +176,23 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         };
 
         tokio::task::spawn(async move {
-            let mut stats_collector = Collector::new(stats_rx, stats_tx.clone());
+            let mut stats_collector = Collector::default();
             stats_collector.collect().await;
         });
 
-        info!("Config autoreloader: {}", config.general.autoreload);
+        info!("Config autoreloader: {}", match config.general.autoreload {
+            Some(interval) => format!("{} ms", interval),
+            None => "disabled".into(),
+        });
 
-        let mut autoreload_interval = tokio::time::interval(tokio::time::Duration::from_millis(15_000));
-        let autoreload_client_server_map = client_server_map.clone();
+        if let Some(interval) = config.general.autoreload {
+            let mut autoreload_interval = tokio::time::interval(tokio::time::Duration::from_millis(interval));
+            let autoreload_client_server_map = client_server_map.clone();
 
-        tokio::task::spawn(async move {
-            loop {
-                autoreload_interval.tick().await;
-                if config.general.autoreload {
-                    info!("Automatically reloading config");
+            tokio::task::spawn(async move {
+                loop {
+                    autoreload_interval.tick().await;
+                    debug!("Automatically reloading config");
 
                     if let Ok(changed) = reload_config(autoreload_client_server_map.clone()).await {
                         if changed {
@@ -196,8 +200,10 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                         }
                     };
                 }
-            }
-        });
+            });
+        };
+
+
 
         #[cfg(windows)]
         let mut term_signal = win_signal::ctrl_close().unwrap();
@@ -282,7 +288,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                     let drain_tx = drain_tx.clone();
                     let client_server_map = client_server_map.clone();
 
-                    let tls_certificate = config.general.tls_certificate.clone();
+                    let tls_certificate = get_config().general.tls_certificate.clone();
+
+                    configure_socket(&socket);
 
                     tokio::task::spawn(async move {
                         let start = chrono::offset::Utc::now().naive_utc();
@@ -293,7 +301,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                             shutdown_rx,
                             drain_tx,
                             admin_only,
-                            tls_certificate.clone(),
+                            tls_certificate,
                             config.general.log_client_connections,
                         )
                         .await
@@ -301,7 +309,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                             Ok(()) => {
                                 let duration = chrono::offset::Utc::now().naive_utc() - start;
 
-                                if config.general.log_client_disconnections {
+                                if get_config().general.log_client_disconnections {
                                     info!(
                                         "Client {:?} disconnected, session duration: {}",
                                         addr,

src/messages.rs

@@ -116,7 +116,10 @@ where
 
 /// Send the startup packet the server. We're pretending we're a Pg client.
 /// This tells the server which user we are and what database we want.
-pub async fn startup(stream: &mut TcpStream, user: &str, database: &str) -> Result<(), Error> {
+pub async fn startup<S>(stream: &mut S, user: &str, database: &str) -> Result<(), Error>
+where
+    S: tokio::io::AsyncWrite + std::marker::Unpin,
+{
     let mut bytes = BytesMut::with_capacity(25);
 
     bytes.put_i32(196608); // Protocol number
@@ -150,6 +153,21 @@ pub async fn startup(stream: &mut TcpStream, user: &str, database: &str) -> Resu
     }
 }
 
+pub async fn ssl_request(stream: &mut TcpStream) -> Result<(), Error> {
+    let mut bytes = BytesMut::with_capacity(12);
+
+    bytes.put_i32(8);
+    bytes.put_i32(80877103);
+
+    match stream.write_all(&bytes).await {
+        Ok(_) => Ok(()),
+        Err(err) => Err(Error::SocketError(format!(
+            "Error writing SSLRequest to server socket - Error: {:?}",
+            err
+        ))),
+    }
+}
+
 /// Parse the params the server sends as a key/value format.
 pub fn parse_params(mut bytes: BytesMut) -> Result<HashMap<String, String>, Error> {
     let mut result = HashMap::new();
@@ -213,7 +231,13 @@ pub fn md5_hash_password(user: &str, password: &str, salt: &[u8]) -> Vec<u8> {
     let output = md5.finalize_reset();
 
     // Second pass
-    md5.update(format!("{:x}", output));
+    md5_hash_second_pass(&(format!("{:x}", output)), salt)
+}
+
+pub fn md5_hash_second_pass(hash: &str, salt: &[u8]) -> Vec<u8> {
+    let mut md5 = Md5::new();
+    // Second pass
+    md5.update(hash);
     md5.update(salt);
 
     let mut password = format!("md5{:x}", md5.finalize())
@@ -247,6 +271,20 @@ where
     write_all(stream, message).await
 }
 
+pub async fn md5_password_with_hash<S>(stream: &mut S, hash: &str, salt: &[u8]) -> Result<(), Error>
+where
+    S: tokio::io::AsyncWrite + std::marker::Unpin,
+{
+    let password = md5_hash_second_pass(hash, salt);
+    let mut message = BytesMut::with_capacity(password.len() as usize + 5);
+
+    message.put_u8(b'p');
+    message.put_i32(password.len() as i32 + 4);
+    message.put_slice(&password[..]);
+
+    write_all(stream, message).await
+}
+
 /// Implements a response to our custom `SET SHARDING KEY`
 /// and `SET SERVER ROLE` commands.
 /// This tells the client we're ready for the next query.
@@ -384,7 +422,7 @@ pub fn row_description(columns: &Vec<(&str, DataType)>) -> BytesMut {
     let mut res = BytesMut::new();
     let mut row_desc = BytesMut::new();
 
-    // how many colums we are storing
+    // how many columns we are storing
     row_desc.put_i16(columns.len() as i16);
 
     for (name, data_type) in columns {
@@ -485,6 +523,29 @@ where
     }
 }
 
+pub async fn write_all_flush<S>(stream: &mut S, buf: &[u8]) -> Result<(), Error>
+where
+    S: tokio::io::AsyncWrite + std::marker::Unpin,
+{
+    match stream.write_all(buf).await {
+        Ok(_) => match stream.flush().await {
+            Ok(_) => Ok(()),
+            Err(err) => {
+                return Err(Error::SocketError(format!(
+                    "Error flushing socket - Error: {:?}",
+                    err
+                )))
+            }
+        },
+        Err(err) => {
+            return Err(Error::SocketError(format!(
+                "Error writing to socket - Error: {:?}",
+                err
+            )))
+        }
+    }
+}
+
 /// Read a complete message from the socket.
 pub async fn read_message<S>(stream: &mut S) -> Result<BytesMut, Error>
 where

src/mirrors.rs

@@ -1,11 +1,14 @@
+use std::sync::Arc;
+
 /// A mirrored PostgreSQL client.
 /// Packets arrive to us through a channel from the main client and we send them to the server.
 use bb8::Pool;
 use bytes::{Bytes, BytesMut};
+use parking_lot::RwLock;
 
 use crate::config::{get_config, Address, Role, User};
-use crate::pool::{ClientServerMap, ServerPool};
-use crate::stats::get_reporter;
+use crate::pool::{ClientServerMap, PoolIdentifier, ServerPool};
+use crate::stats::PoolStats;
 use log::{error, info, trace, warn};
 use tokio::sync::mpsc::{channel, Receiver, Sender};
 
@@ -21,20 +24,25 @@ impl MirroredClient {
     async fn create_pool(&self) -> Pool<ServerPool> {
         let config = get_config();
         let default = std::time::Duration::from_millis(10_000).as_millis() as u64;
-        let (connection_timeout, idle_timeout) = match config.pools.get(&self.address.pool_name) {
-            Some(cfg) => (
-                cfg.connect_timeout.unwrap_or(default),
-                cfg.idle_timeout.unwrap_or(default),
-            ),
-            None => (default, default),
-        };
+        let (connection_timeout, idle_timeout, cfg) =
+            match config.pools.get(&self.address.pool_name) {
+                Some(cfg) => (
+                    cfg.connect_timeout.unwrap_or(default),
+                    cfg.idle_timeout.unwrap_or(default),
+                    cfg.clone(),
+                ),
+                None => (default, default, crate::config::Pool::default()),
+            };
+
+        let identifier = PoolIdentifier::new(&self.database, &self.user.username);
 
         let manager = ServerPool::new(
             self.address.clone(),
             self.user.clone(),
             self.database.as_str(),
             ClientServerMap::default(),
-            get_reporter(),
+            Arc::new(PoolStats::new(identifier, cfg.clone())),
+            Arc::new(RwLock::new(None)),
         );
 
         Pool::builder()

src/multi_logger.rs

@@ -17,7 +17,7 @@ use log::{Level, Log, Metadata, Record, SetLoggerError};
 //
 // So to summarize, if no `STDOUT_LOG` env var is present, the logger is the default logger. If `STDOUT_LOG` is set, everything
 // but errors, that matches the log level set in the `STDOUT_LOG` env var is sent to stdout. You can have also some esoteric configuration
-// where you set `RUST_LOG=debug` and `STDOUT_LOG=info`, in here, erros will go to stderr, warns and infos to stdout and debugs to stderr.
+// where you set `RUST_LOG=debug` and `STDOUT_LOG=info`, in here, errors will go to stderr, warns and infos to stdout and debugs to stderr.
 //
 pub struct MultiLogger {
     stderr_logger: env_logger::Logger,

src/pool.rs

@@ -20,9 +20,10 @@ use tokio::sync::Notify;
 use crate::config::{get_config, Address, General, LoadBalancingMode, PoolMode, Role, User};
 use crate::errors::Error;
 
+use crate::auth_passthrough::AuthPassthrough;
 use crate::server::Server;
 use crate::sharding::ShardingFunction;
-use crate::stats::{get_reporter, Reporter};
+use crate::stats::{AddressStats, ClientStats, PoolStats, ServerStats};
 
 pub type ProcessId = i32;
 pub type SecretKey = i32;
@@ -51,7 +52,7 @@ pub enum BanReason {
 
 /// An identifier for a PgCat pool,
 /// a database visible to clients.
-#[derive(Hash, Debug, Clone, PartialEq, Eq)]
+#[derive(Hash, Debug, Clone, PartialEq, Eq, Default)]
 pub struct PoolIdentifier {
     // The name of the database clients want to connect to.
     pub db: String,
@@ -123,6 +124,11 @@ pub struct PoolSettings {
 
     // Limit how much of each query is searched for a potential shard regex match
     pub regex_search_limit: usize,
+
+    // Auth query parameters
+    pub auth_query: Option<String>,
+    pub auth_query_user: Option<String>,
+    pub auth_query_password: Option<String>,
 }
 
 impl Default for PoolSettings {
@@ -143,6 +149,9 @@ impl Default for PoolSettings {
             sharding_key_regex: None,
             shard_id_regex: None,
             regex_search_limit: 1000,
+            auth_query: None,
+            auth_query_user: None,
+            auth_query_password: None,
         }
     }
 }
@@ -161,10 +170,6 @@ pub struct ConnectionPool {
     /// that should not be queried.
     banlist: BanList,
 
-    /// The statistics aggregator runs in a separate task
-    /// and receives stats from clients, servers, and the pool.
-    stats: Reporter,
-
     /// The server information (K messages) have to be passed to the
     /// clients on startup. We pre-connect to all shards and replicas
     /// on pool creation and save the K messages here.
@@ -185,6 +190,11 @@ pub struct ConnectionPool {
     /// If the pool has been paused or not.
     paused: Arc<AtomicBool>,
     paused_waiter: Arc<Notify>,
+
+    pub stats: Arc<PoolStats>,
+
+    /// AuthInfo
+    pub auth_hash: Arc<RwLock<Option<String>>>,
 }
 
 impl ConnectionPool {
@@ -201,6 +211,7 @@ impl ConnectionPool {
             // There is one pool per database/user pair.
             for user in pool_config.users.values() {
                 let old_pool_ref = get_pool(pool_name, &user.username);
+                let identifier = PoolIdentifier::new(pool_name, &user.username);
 
                 match old_pool_ref {
                     Some(pool) => {
@@ -211,10 +222,7 @@ impl ConnectionPool {
                                 "[pool: {}][user: {}] has not changed",
                                 pool_name, user.username
                             );
-                            new_pools.insert(
-                                PoolIdentifier::new(pool_name, &user.username),
-                                pool.clone(),
-                            );
+                            new_pools.insert(identifier.clone(), pool.clone());
                             continue;
                         }
                     }
@@ -234,9 +242,14 @@ impl ConnectionPool {
                     .clone()
                     .into_keys()
                     .collect::<Vec<String>>();
+                let pool_stats = Arc::new(PoolStats::new(identifier, pool_config.clone()));
+
+                // Allow the pool to be seen in statistics
+                pool_stats.register(pool_stats.clone());
 
                 // Sort by shard number to ensure consistency.
                 shard_ids.sort_by_key(|k| k.parse::<i64>().unwrap());
+                let pool_auth_hash: Arc<RwLock<Option<String>>> = Arc::new(RwLock::new(None));
 
                 for shard_idx in &shard_ids {
                     let shard = &pool_config.shards[shard_idx];
@@ -266,6 +279,7 @@ impl ConnectionPool {
                                     username: user.username.clone(),
                                     pool_name: pool_name.clone(),
                                     mirrors: vec![],
+                                    stats: Arc::new(AddressStats::default()),
                                 });
                                 address_id += 1;
                             }
@@ -283,6 +297,7 @@ impl ConnectionPool {
                             username: user.username.clone(),
                             pool_name: pool_name.clone(),
                             mirrors: mirror_addresses,
+                            stats: Arc::new(AddressStats::default()),
                         };
 
                         address_id += 1;
@@ -291,12 +306,48 @@ impl ConnectionPool {
                             replica_number += 1;
                         }
 
+                        // We assume every server in the pool share user/passwords
+                        let auth_passthrough = AuthPassthrough::from_pool_config(pool_config);
+
+                        if let Some(apt) = &auth_passthrough {
+                            match apt.fetch_hash(&address).await {
+                                Ok(ok) => {
+                                    if let Some(ref pool_auth_hash_value) = *(pool_auth_hash.read())
+                                    {
+                                        if ok != *pool_auth_hash_value {
+                                            warn!(
+                                                "Hash is not the same across shards \
+                                                of the same pool, client auth will \
+                                                be done using last obtained hash. \
+                                                Server: {}:{}, Database: {}",
+                                                server.host, server.port, shard.database,
+                                            );
+                                        }
+                                    }
+
+                                    debug!("Hash obtained for {:?}", address);
+
+                                    {
+                                        let mut pool_auth_hash = pool_auth_hash.write();
+                                        *pool_auth_hash = Some(ok.clone());
+                                    }
+                                }
+                                Err(err) => warn!(
+                                    "Could not obtain password hashes \
+                                        using auth_query config, ignoring. \
+                                        Error: {:?}",
+                                    err,
+                                ),
+                            }
+                        }
+
                         let manager = ServerPool::new(
                             address.clone(),
                             user.clone(),
                             &shard.database,
                             client_server_map.clone(),
-                            get_reporter(),
+                            pool_stats.clone(),
+                            pool_auth_hash.clone(),
                         );
 
                         let connect_timeout = match pool_config.connect_timeout {
@@ -309,14 +360,23 @@ impl ConnectionPool {
                             None => config.general.idle_timeout,
                         };
 
+                        let server_lifetime = match user.server_lifetime {
+                            Some(server_lifetime) => server_lifetime,
+                            None => match pool_config.server_lifetime {
+                                Some(server_lifetime) => server_lifetime,
+                                None => config.general.server_lifetime,
+                            },
+                        };
+
                         let pool = Pool::builder()
                             .max_size(user.pool_size)
+                            .min_idle(user.min_pool_size)
                             .connection_timeout(std::time::Duration::from_millis(connect_timeout))
                             .idle_timeout(Some(std::time::Duration::from_millis(idle_timeout)))
+                            .max_lifetime(Some(std::time::Duration::from_millis(server_lifetime)))
                             .test_on_check_out(false)
                             .build(manager)
-                            .await
-                            .unwrap();
+                            .await?;
 
                         pools.push(pool);
                         servers.push(address);
@@ -328,16 +388,26 @@ impl ConnectionPool {
                 }
 
                 assert_eq!(shards.len(), addresses.len());
+                if let Some(ref _auth_hash) = *(pool_auth_hash.clone().read()) {
+                    info!(
+                        "Auth hash obtained from query_auth for pool {{ name: {}, user: {} }}",
+                        pool_name, user.username
+                    );
+                }
 
                 let pool = ConnectionPool {
                     databases: shards,
+                    stats: pool_stats,
                     addresses,
                     banlist: Arc::new(RwLock::new(banlist)),
-                    stats: get_reporter(),
                     config_hash: new_pool_hash_value,
                     server_info: Arc::new(RwLock::new(BytesMut::new())),
+                    auth_hash: pool_auth_hash,
                     settings: PoolSettings {
-                        pool_mode: pool_config.pool_mode,
+                        pool_mode: match user.pool_mode {
+                            Some(pool_mode) => pool_mode,
+                            None => pool_config.pool_mode,
+                        },
                         load_balancing_mode: pool_config.load_balancing_mode,
                         // shards: pool_config.shards.clone(),
                         shards: shard_ids.len(),
@@ -364,6 +434,9 @@ impl ConnectionPool {
                             .clone()
                             .map(|regex| Regex::new(regex.as_str()).unwrap()),
                         regex_search_limit: pool_config.regex_search_limit.unwrap_or(1000),
+                        auth_query: pool_config.auth_query.clone(),
+                        auth_query_user: pool_config.auth_query_user.clone(),
+                        auth_query_password: pool_config.auth_query_password.clone(),
                     },
                     validated: Arc::new(AtomicBool::new(false)),
                     paused: Arc::new(AtomicBool::new(false)),
@@ -387,7 +460,8 @@ impl ConnectionPool {
         Ok(())
     }
 
-    /// Connect to all shards and grab server information.
+    /// Connect to all shards, grab server information, and possibly
+    /// passwords to use in client auth.
     /// Return server information we will pass to the clients
     /// when they connect.
     /// This also warms up the pool for clients that connect when
@@ -476,9 +550,9 @@ impl ConnectionPool {
     /// Get a connection from the pool.
     pub async fn get(
         &self,
-        shard: usize,           // shard number
-        role: Option<Role>,     // primary or replica
-        client_process_id: i32, // client id
+        shard: usize,               // shard number
+        role: Option<Role>,         // primary or replica
+        client_stats: &ClientStats, // client id
     ) -> Result<(PooledConnection<'_, ServerPool>, Address), Error> {
         let mut candidates: Vec<&Address> = self.addresses[shard]
             .iter()
@@ -517,7 +591,7 @@ impl ConnectionPool {
 
             // Indicate we're waiting on a server connection from a pool.
             let now = Instant::now();
-            self.stats.client_waiting(client_process_id);
+            client_stats.waiting();
 
             // Check if we can connect
             let mut conn = match self.databases[address.shard][address.address_index]
@@ -527,9 +601,10 @@ impl ConnectionPool {
                 Ok(conn) => conn,
                 Err(err) => {
                     error!("Banning instance {:?}, error: {:?}", address, err);
-                    self.ban(address, BanReason::FailedCheckout, client_process_id);
-                    self.stats
-                        .client_checkout_error(client_process_id, address.id);
+                    self.ban(address, BanReason::FailedCheckout, Some(client_stats));
+                    address.stats.error();
+                    client_stats.idle();
+                    client_stats.checkout_error();
                     continue;
                 }
             };
@@ -546,18 +621,18 @@ impl ConnectionPool {
             // since we last checked the server is ok.
             // Health checks are pretty expensive.
             if !require_healthcheck {
-                self.stats.checkout_time(
-                    now.elapsed().as_micros(),
-                    client_process_id,
-                    server.server_id(),
-                );
-                self.stats
-                    .server_active(client_process_id, server.server_id());
+                let checkout_time: u64 = now.elapsed().as_micros() as u64;
+                client_stats.checkout_time(checkout_time);
+                server
+                    .stats()
+                    .checkout_time(checkout_time, client_stats.application_name());
+                server.stats().active(client_stats.application_name());
+
                 return Ok((conn, address.clone()));
             }
 
             if self
-                .run_health_check(address, server, now, client_process_id)
+                .run_health_check(address, server, now, client_stats)
                 .await
             {
                 return Ok((conn, address.clone()));
@@ -565,7 +640,6 @@ impl ConnectionPool {
                 continue;
             }
         }
-
         Err(Error::AllServersDown)
     }
 
@@ -574,11 +648,11 @@ impl ConnectionPool {
         address: &Address,
         server: &mut Server,
         start: Instant,
-        client_process_id: i32,
+        client_info: &ClientStats,
     ) -> bool {
         debug!("Running health check on server {:?}", address);
 
-        self.stats.server_tested(server.server_id());
+        server.stats().tested();
 
         match tokio::time::timeout(
             tokio::time::Duration::from_millis(self.settings.healthcheck_timeout),
@@ -589,13 +663,13 @@ impl ConnectionPool {
             // Check if health check succeeded.
             Ok(res) => match res {
                 Ok(_) => {
-                    self.stats.checkout_time(
-                        start.elapsed().as_micros(),
-                        client_process_id,
-                        server.server_id(),
-                    );
-                    self.stats
-                        .server_active(client_process_id, server.server_id());
+                    let checkout_time: u64 = start.elapsed().as_micros() as u64;
+                    client_info.checkout_time(checkout_time);
+                    server
+                        .stats()
+                        .checkout_time(checkout_time, client_info.application_name());
+                    server.stats().active(client_info.application_name());
+
                     return true;
                 }
 
@@ -620,14 +694,14 @@ impl ConnectionPool {
         // Don't leave a bad connection in the pool.
         server.mark_bad();
 
-        self.ban(&address, BanReason::FailedHealthCheck, client_process_id);
+        self.ban(&address, BanReason::FailedHealthCheck, Some(client_info));
         return false;
     }
 
     /// Ban an address (i.e. replica). It no longer will serve
     /// traffic for any new transactions. Existing transactions on that replica
     /// will finish successfully or error out to the clients.
-    pub fn ban(&self, address: &Address, reason: BanReason, client_id: i32) {
+    pub fn ban(&self, address: &Address, reason: BanReason, client_info: Option<&ClientStats>) {
         // Primary can never be banned
         if address.role == Role::Primary {
             return;
@@ -636,7 +710,10 @@ impl ConnectionPool {
         let now = chrono::offset::Utc::now().naive_utc();
         let mut guard = self.banlist.write();
         error!("Banning {:?}", address);
-        self.stats.client_ban_error(client_id, address.id);
+        if let Some(client_info) = client_info {
+            client_info.ban_error();
+            address.stats.error();
+        }
         guard[address.shard].insert(address.clone(), (reason, now));
     }
 
@@ -797,7 +874,8 @@ pub struct ServerPool {
     user: User,
     database: String,
     client_server_map: ClientServerMap,
-    stats: Reporter,
+    stats: Arc<PoolStats>,
+    auth_hash: Arc<RwLock<Option<String>>>,
 }
 
 impl ServerPool {
@@ -806,14 +884,16 @@ impl ServerPool {
         user: User,
         database: &str,
         client_server_map: ClientServerMap,
-        stats: Reporter,
+        stats: Arc<PoolStats>,
+        auth_hash: Arc<RwLock<Option<String>>>,
     ) -> ServerPool {
         ServerPool {
             address,
-            user,
+            user: user.clone(),
             database: database.to_string(),
             client_server_map,
             stats,
+            auth_hash,
         }
     }
 }
@@ -826,34 +906,32 @@ impl ManageConnection for ServerPool {
     /// Attempts to create a new connection.
     async fn connect(&self) -> Result<Self::Connection, Self::Error> {
         info!("Creating a new server connection {:?}", self.address);
-        let server_id = rand::random::<i32>();
 
-        self.stats.server_register(
-            server_id,
-            self.address.id,
-            self.address.name(),
-            self.address.pool_name.clone(),
-            self.address.username.clone(),
-        );
-        self.stats.server_login(server_id);
+        let stats = Arc::new(ServerStats::new(
+            self.address.clone(),
+            self.stats.clone(),
+            tokio::time::Instant::now(),
+        ));
+
+        stats.register(stats.clone());
 
         // Connect to the PostgreSQL server.
         match Server::startup(
-            server_id,
             &self.address,
             &self.user,
             &self.database,
             self.client_server_map.clone(),
-            self.stats.clone(),
+            stats.clone(),
+            self.auth_hash.clone(),
         )
         .await
         {
             Ok(conn) => {
-                self.stats.server_idle(server_id);
+                stats.idle();
                 Ok(conn)
             }
             Err(err) => {
-                self.stats.server_disconnecting(server_id);
+                stats.disconnect();
                 Err(err)
             }
         }
@@ -881,11 +959,3 @@ pub fn get_pool(db: &str, user: &str) -> Option<ConnectionPool> {
 pub fn get_all_pools() -> HashMap<PoolIdentifier, ConnectionPool> {
     (*(*POOLS.load())).clone()
 }
-
-/// How many total servers we have in the config.
-pub fn get_number_of_addresses() -> usize {
-    get_all_pools()
-        .iter()
-        .map(|(_, pool)| pool.databases())
-        .sum()
-}

src/prometheus.rs

@@ -5,10 +5,12 @@ use phf::phf_map;
 use std::collections::HashMap;
 use std::fmt;
 use std::net::SocketAddr;
+use std::sync::atomic::Ordering;
+use std::sync::Arc;
 
 use crate::config::Address;
 use crate::pool::get_all_pools;
-use crate::stats::{get_address_stats, get_pool_stats, get_server_stats, ServerInformation};
+use crate::stats::{get_pool_stats, get_server_stats, ServerStats};
 
 struct MetricHelpType {
     help: &'static str,
@@ -220,7 +222,7 @@ impl<Value: fmt::Display> PrometheusMetric<Value> {
         Self::from_name(&format!("servers_{}", name), value, labels)
     }
 
-    fn from_address(address: &Address, name: &str, value: i64) -> Option<PrometheusMetric<i64>> {
+    fn from_address(address: &Address, name: &str, value: u64) -> Option<PrometheusMetric<u64>> {
         let mut labels = HashMap::new();
         labels.insert("host", address.host.clone());
         labels.insert("shard", address.shard.to_string());
@@ -231,7 +233,7 @@ impl<Value: fmt::Display> PrometheusMetric<Value> {
         Self::from_name(&format!("stats_{}", name), value, labels)
     }
 
-    fn from_pool(pool: &(String, String), name: &str, value: i64) -> Option<PrometheusMetric<i64>> {
+    fn from_pool(pool: &(String, String), name: &str, value: u64) -> Option<PrometheusMetric<u64>> {
         let mut labels = HashMap::new();
         labels.insert("pool", pool.0.clone());
         labels.insert("user", pool.1.clone());
@@ -261,20 +263,18 @@ async fn prometheus_stats(request: Request<Body>) -> Result<Response<Body>, hype
 
 // Adds metrics shown in a SHOW STATS admin command.
 fn push_address_stats(lines: &mut Vec<String>) {
-    let address_stats: HashMap<usize, HashMap<String, i64>> = get_address_stats();
     for (_, pool) in get_all_pools() {
         for shard in 0..pool.shards() {
             for server in 0..pool.servers(shard) {
                 let address = pool.address(shard, server);
-                if let Some(address_stats) = address_stats.get(&address.id) {
-                    for (key, value) in address_stats.iter() {
-                        if let Some(prometheus_metric) =
-                            PrometheusMetric::<i64>::from_address(address, key, *value)
-                        {
-                            lines.push(prometheus_metric.to_string());
-                        } else {
-                            warn!("Metric {} not implemented for {}", key, address.name());
-                        }
+                let stats = &*address.stats;
+                for (key, value) in stats.clone() {
+                    if let Some(prometheus_metric) =
+                        PrometheusMetric::<u64>::from_address(address, &key, value)
+                    {
+                        lines.push(prometheus_metric.to_string());
+                    } else {
+                        warn!("Metric {} not implemented for {}", key, address.name());
                     }
                 }
             }
@@ -286,8 +286,9 @@ fn push_address_stats(lines: &mut Vec<String>) {
 fn push_pool_stats(lines: &mut Vec<String>) {
     let pool_stats = get_pool_stats();
     for (pool, stats) in pool_stats.iter() {
-        for (name, value) in stats.iter() {
-            if let Some(prometheus_metric) = PrometheusMetric::<i64>::from_pool(pool, name, *value)
+        let stats = &**stats;
+        for (name, value) in stats.clone() {
+            if let Some(prometheus_metric) = PrometheusMetric::<u64>::from_pool(pool, &name, value)
             {
                 lines.push(prometheus_metric.to_string());
             } else {
@@ -330,9 +331,9 @@ fn push_database_stats(lines: &mut Vec<String>) {
 // Adds relevant metrics shown in a SHOW SERVERS admin command.
 fn push_server_stats(lines: &mut Vec<String>) {
     let server_stats = get_server_stats();
-    let mut server_stats_by_addresses = HashMap::<String, ServerInformation>::new();
-    for (_, info) in server_stats {
-        server_stats_by_addresses.insert(info.address_name.clone(), info);
+    let mut server_stats_by_addresses = HashMap::<String, Arc<ServerStats>>::new();
+    for (_, stats) in server_stats {
+        server_stats_by_addresses.insert(stats.address_name(), stats);
     }
 
     for (_, pool) in get_all_pools() {
@@ -341,11 +342,23 @@ fn push_server_stats(lines: &mut Vec<String>) {
                 let address = pool.address(shard, server);
                 if let Some(server_info) = server_stats_by_addresses.get(&address.name()) {
                     let metrics = [
-                        ("bytes_received", server_info.bytes_received),
-                        ("bytes_sent", server_info.bytes_sent),
-                        ("transaction_count", server_info.transaction_count),
-                        ("query_count", server_info.query_count),
-                        ("error_count", server_info.error_count),
+                        (
+                            "bytes_received",
+                            server_info.bytes_received.load(Ordering::Relaxed),
+                        ),
+                        ("bytes_sent", server_info.bytes_sent.load(Ordering::Relaxed)),
+                        (
+                            "transaction_count",
+                            server_info.transaction_count.load(Ordering::Relaxed),
+                        ),
+                        (
+                            "query_count",
+                            server_info.query_count.load(Ordering::Relaxed),
+                        ),
+                        (
+                            "error_count",
+                            server_info.error_count.load(Ordering::Relaxed),
+                        ),
                     ];
                     for (key, value) in metrics {
                         if let Some(prometheus_metric) =

src/query_router.rs

@@ -1,4 +1,4 @@
-/// Route queries automatically based on explicitely requested
+/// Route queries automatically based on explicitly requested
 /// or implied query characteristics.
 use bytes::{Buf, BytesMut};
 use log::{debug, error};
@@ -1110,6 +1110,9 @@ mod test {
             sharding_key_regex: None,
             shard_id_regex: None,
             regex_search_limit: 1000,
+            auth_query: None,
+            auth_query_password: None,
+            auth_query_user: None,
         };
         let mut qr = QueryRouter::new();
         assert_eq!(qr.active_role, None);
@@ -1171,6 +1174,9 @@ mod test {
             sharding_key_regex: Some(Regex::new(r"/\* sharding_key: (\d+) \*/").unwrap()),
             shard_id_regex: Some(Regex::new(r"/\* shard_id: (\d+) \*/").unwrap()),
             regex_search_limit: 1000,
+            auth_query: None,
+            auth_query_password: None,
+            auth_query_user: None,
         };
         let mut qr = QueryRouter::new();
         qr.update_pool_settings(pool_settings.clone());

src/server.rs

@@ -1,37 +1,114 @@
 /// Implementation of the PostgreSQL server (database) protocol.
 /// Here we are pretending to the a Postgres client.
 use bytes::{Buf, BufMut, BytesMut};
+use fallible_iterator::FallibleIterator;
 use log::{debug, error, info, trace, warn};
+use parking_lot::{Mutex, RwLock};
+use postgres_protocol::message;
+use std::collections::HashMap;
 use std::io::Read;
+use std::sync::Arc;
 use std::time::SystemTime;
-use tokio::io::{AsyncReadExt, BufReader};
-use tokio::net::{
-    tcp::{OwnedReadHalf, OwnedWriteHalf},
-    TcpStream,
-};
+use tokio::io::{AsyncRead, AsyncReadExt, AsyncWrite, BufStream};
+use tokio::net::TcpStream;
+use tokio_rustls::rustls::{OwnedTrustAnchor, RootCertStore};
+use tokio_rustls::{client::TlsStream, TlsConnector};
 
-use crate::config::{Address, User};
+use crate::config::{get_config, Address, User};
 use crate::constants::*;
-use crate::errors::Error;
+use crate::errors::{Error, ServerIdentifier};
 use crate::messages::*;
 use crate::mirrors::MirroringManager;
 use crate::pool::ClientServerMap;
 use crate::scram::ScramSha256;
-use crate::stats::Reporter;
+use crate::stats::ServerStats;
+use std::io::Write;
+
+use pin_project::pin_project;
+
+#[pin_project(project = SteamInnerProj)]
+pub enum StreamInner {
+    Plain {
+        #[pin]
+        stream: TcpStream,
+    },
+    Tls {
+        #[pin]
+        stream: TlsStream<TcpStream>,
+    },
+}
+
+impl AsyncWrite for StreamInner {
+    fn poll_write(
+        self: std::pin::Pin<&mut Self>,
+        cx: &mut std::task::Context<'_>,
+        buf: &[u8],
+    ) -> std::task::Poll<Result<usize, std::io::Error>> {
+        let this = self.project();
+        match this {
+            SteamInnerProj::Tls { stream } => stream.poll_write(cx, buf),
+            SteamInnerProj::Plain { stream } => stream.poll_write(cx, buf),
+        }
+    }
+
+    fn poll_flush(
+        self: std::pin::Pin<&mut Self>,
+        cx: &mut std::task::Context<'_>,
+    ) -> std::task::Poll<Result<(), std::io::Error>> {
+        let this = self.project();
+        match this {
+            SteamInnerProj::Tls { stream } => stream.poll_flush(cx),
+            SteamInnerProj::Plain { stream } => stream.poll_flush(cx),
+        }
+    }
+
+    fn poll_shutdown(
+        self: std::pin::Pin<&mut Self>,
+        cx: &mut std::task::Context<'_>,
+    ) -> std::task::Poll<Result<(), std::io::Error>> {
+        let this = self.project();
+        match this {
+            SteamInnerProj::Tls { stream } => stream.poll_shutdown(cx),
+            SteamInnerProj::Plain { stream } => stream.poll_shutdown(cx),
+        }
+    }
+}
+
+impl AsyncRead for StreamInner {
+    fn poll_read(
+        self: std::pin::Pin<&mut Self>,
+        cx: &mut std::task::Context<'_>,
+        buf: &mut tokio::io::ReadBuf<'_>,
+    ) -> std::task::Poll<std::io::Result<()>> {
+        let this = self.project();
+        match this {
+            SteamInnerProj::Tls { stream } => stream.poll_read(cx, buf),
+            SteamInnerProj::Plain { stream } => stream.poll_read(cx, buf),
+        }
+    }
+}
+
+impl StreamInner {
+    pub fn try_write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
+        match self {
+            StreamInner::Tls { stream } => {
+                let r = stream.get_mut();
+                let mut w = r.1.writer();
+                w.write(buf)
+            }
+            StreamInner::Plain { stream } => stream.try_write(buf),
+        }
+    }
+}
 
 /// Server state.
 pub struct Server {
-    server_id: i32,
-
     /// Server host, e.g. localhost,
     /// port, e.g. 5432, and role, e.g. primary or replica.
     address: Address,
 
-    /// Buffered read socket.
-    read: BufReader<OwnedReadHalf>,
-
-    /// Unbuffered write socket (our client code buffers).
-    write: OwnedWriteHalf,
+    /// Server TCP connection.
+    stream: BufStream<StreamInner>,
 
     /// Our server response buffer. We buffer data before we give it to the client.
     buffer: BytesMut,
@@ -62,7 +139,7 @@ pub struct Server {
     connected_at: chrono::naive::NaiveDateTime,
 
     /// Reports various metrics, e.g. data sent & received.
-    stats: Reporter,
+    stats: Arc<ServerStats>,
 
     /// Application name using the server at the moment.
     application_name: String,
@@ -77,12 +154,12 @@ impl Server {
     /// Pretend to be the Postgres client and connect to the server given host, port and credentials.
     /// Perform the authentication and return the server in a ready for query state.
     pub async fn startup(
-        server_id: i32,
         address: &Address,
         user: &User,
         database: &str,
         client_server_map: ClientServerMap,
-        stats: Reporter,
+        stats: Arc<ServerStats>,
+        auth_hash: Arc<RwLock<Option<String>>>,
     ) -> Result<Server, Error> {
         let mut stream =
             match TcpStream::connect(&format!("{}:{}", &address.host, address.port)).await {
@@ -95,30 +172,137 @@ impl Server {
                     )));
                 }
             };
+
+        // TCP timeouts.
         configure_socket(&stream);
 
+        let config = get_config();
+
+        let mut stream = if config.general.server_tls {
+            // Request a TLS connection
+            ssl_request(&mut stream).await?;
+
+            let response = match stream.read_u8().await {
+                Ok(response) => response as char,
+                Err(err) => {
+                    return Err(Error::SocketError(format!(
+                        "Server socket error: {:?}",
+                        err
+                    )))
+                }
+            };
+
+            match response {
+                // Server supports TLS
+                'S' => {
+                    debug!("Connecting to server using TLS");
+
+                    let mut root_store = RootCertStore::empty();
+                    root_store.add_server_trust_anchors(
+                        webpki_roots::TLS_SERVER_ROOTS.0.iter().map(|ta| {
+                            OwnedTrustAnchor::from_subject_spki_name_constraints(
+                                ta.subject,
+                                ta.spki,
+                                ta.name_constraints,
+                            )
+                        }),
+                    );
+
+                    let mut tls_config = rustls::ClientConfig::builder()
+                        .with_safe_defaults()
+                        .with_root_certificates(root_store)
+                        .with_no_client_auth();
+
+                    // Equivalent to sslmode=prefer which is fine most places.
+                    // If you want verify-full, change `verify_server_certificate` to true.
+                    if !config.general.verify_server_certificate {
+                        let mut dangerous = tls_config.dangerous();
+                        dangerous.set_certificate_verifier(Arc::new(
+                            crate::tls::NoCertificateVerification {},
+                        ));
+                    }
+
+                    let connector = TlsConnector::from(Arc::new(tls_config));
+                    let stream = match connector
+                        .connect(address.host.as_str().try_into().unwrap(), stream)
+                        .await
+                    {
+                        Ok(stream) => stream,
+                        Err(err) => {
+                            return Err(Error::SocketError(format!("Server TLS error: {:?}", err)))
+                        }
+                    };
+
+                    StreamInner::Tls { stream }
+                }
+
+                // Server does not support TLS
+                'N' => StreamInner::Plain { stream },
+
+                // Something else?
+                m => {
+                    return Err(Error::SocketError(format!(
+                        "Unknown message: {}",
+                        m as char
+                    )));
+                }
+            }
+        } else {
+            StreamInner::Plain { stream }
+        };
+
+        // let (read, write) = split(stream);
+        // let (mut read, mut write) = (ReadInner::Plain { stream: read }, WriteInner::Plain { stream: write });
+
         trace!("Sending StartupMessage");
 
         // StartupMessage
-        startup(&mut stream, &user.username, database).await?;
+        let username = match user.server_username {
+            Some(ref server_username) => server_username,
+            None => &user.username,
+        };
+
+        let password = match user.server_password {
+            Some(ref server_password) => Some(server_password),
+            None => match user.password {
+                Some(ref password) => Some(password),
+                None => None,
+            },
+        };
+
+        startup(&mut stream, username, database).await?;
 
         let mut server_info = BytesMut::new();
         let mut process_id: i32 = 0;
         let mut secret_key: i32 = 0;
+        let server_identifier = ServerIdentifier::new(username, &database);
 
         // We'll be handling multiple packets, but they will all be structured the same.
         // We'll loop here until this exchange is complete.
-        let mut scram = ScramSha256::new(&user.password);
+        let mut scram: Option<ScramSha256> = match password {
+            Some(password) => Some(ScramSha256::new(password)),
+            None => None,
+        };
 
         loop {
             let code = match stream.read_u8().await {
                 Ok(code) => code as char,
-                Err(_) => return Err(Error::SocketError(format!("Error reading message code on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                Err(_) => {
+                    return Err(Error::ServerStartupError(
+                        "message code".into(),
+                        server_identifier,
+                    ))
+                }
             };
 
             let len = match stream.read_i32().await {
                 Ok(len) => len,
-                Err(_) => return Err(Error::SocketError(format!("Error reading message len on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                Err(_) => {
+                    return Err(Error::ServerStartupError(
+                        "message len".into(),
+                        server_identifier,
+                    ))
+                }
             };
 
             trace!("Message: {}", code);
@@ -129,7 +313,12 @@ impl Server {
                     // Determine which kind of authentication is required, if any.
                     let auth_code = match stream.read_i32().await {
                         Ok(auth_code) => auth_code,
-                        Err(_) => return Err(Error::SocketError(format!("Error reading auth code on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "auth code".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
 
                     trace!("Auth: {}", auth_code);
@@ -142,32 +331,79 @@ impl Server {
 
                             match stream.read_exact(&mut salt).await {
                                 Ok(_) => (),
-                                Err(_) => return Err(Error::SocketError(format!("Error reading salt on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                                Err(_) => {
+                                    return Err(Error::ServerStartupError(
+                                        "salt".into(),
+                                        server_identifier,
+                                    ))
+                                }
                             };
 
-                            md5_password(&mut stream, &user.username, &user.password, &salt[..])
-                                .await?;
+                            match password {
+                                // Using plaintext password
+                                Some(password) => {
+                                    md5_password(&mut stream, username, password, &salt[..]).await?
+                                }
+
+                                // Using auth passthrough, in this case we should already have a
+                                // hash obtained when the pool was validated. If we reach this point
+                                // and don't have a hash, we return an error.
+                                None => {
+                                    let option_hash = (*auth_hash.read()).clone();
+                                    match option_hash {
+                                        Some(hash) =>
+                                            md5_password_with_hash(
+                                                &mut stream,
+                                                &hash,
+                                                &salt[..],
+                                            )
+                                            .await?,
+                                        None => return Err(
+                                            Error::ServerAuthError(
+                                                "Auth passthrough (auth_query) failed and no user password is set in cleartext".into(),
+                                                server_identifier
+                                            )
+                                        ),
+                                    }
+                                }
+                            }
                         }
 
                         AUTHENTICATION_SUCCESSFUL => (),
 
                         SASL => {
+                            if scram.is_none() {
+                                return Err(Error::ServerAuthError(
+                                    "SASL auth required and no password specified. \
+                                    Auth passthrough (auth_query) method is currently \
+                                    unsupported for SASL auth"
+                                        .into(),
+                                    server_identifier,
+                                ));
+                            }
+
                             debug!("Starting SASL authentication");
+
                             let sasl_len = (len - 8) as usize;
                             let mut sasl_auth = vec![0u8; sasl_len];
 
                             match stream.read_exact(&mut sasl_auth).await {
                                 Ok(_) => (),
-                                Err(_) => return Err(Error::SocketError(format!("Error reading sasl message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                                Err(_) => {
+                                    return Err(Error::ServerStartupError(
+                                        "sasl message".into(),
+                                        server_identifier,
+                                    ))
+                                }
                             };
 
                             let sasl_type = String::from_utf8_lossy(&sasl_auth[..sasl_len - 2]);
 
-                            if sasl_type == SCRAM_SHA_256 {
+                            if sasl_type.contains(SCRAM_SHA_256) {
                                 debug!("Using {}", SCRAM_SHA_256);
 
                                 // Generate client message.
-                                let sasl_response = scram.message();
+                                let sasl_response = scram.as_mut().unwrap().message();
 
                                 // SASLInitialResponse (F)
                                 let mut res = BytesMut::new();
@@ -186,7 +422,7 @@ impl Server {
                                 res.put_i32(sasl_response.len() as i32);
                                 res.put(sasl_response);
 
-                                write_all(&mut stream, res).await?;
+                                write_all_flush(&mut stream, &res).await?;
                             } else {
                                 error!("Unsupported SCRAM version: {}", sasl_type);
                                 return Err(Error::ServerError);
@@ -200,11 +436,16 @@ impl Server {
 
                             match stream.read_exact(&mut sasl_data).await {
                                 Ok(_) => (),
-                                Err(_) => return Err(Error::SocketError(format!("Error reading sasl cont message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                                Err(_) => {
+                                    return Err(Error::ServerStartupError(
+                                        "sasl cont message".into(),
+                                        server_identifier,
+                                    ))
+                                }
                             };
 
                             let msg = BytesMut::from(&sasl_data[..]);
-                            let sasl_response = scram.update(&msg)?;
+                            let sasl_response = scram.as_mut().unwrap().update(&msg)?;
 
                             // SASLResponse
                             let mut res = BytesMut::new();
@@ -212,7 +453,7 @@ impl Server {
                             res.put_i32(4 + sasl_response.len() as i32);
                             res.put(sasl_response);
 
-                            write_all(&mut stream, res).await?;
+                            write_all_flush(&mut stream, &res).await?;
                         }
 
                         SASL_FINAL => {
@@ -221,10 +462,19 @@ impl Server {
                             let mut sasl_final = vec![0u8; len as usize - 8];
                             match stream.read_exact(&mut sasl_final).await {
                                 Ok(_) => (),
-                                Err(_) => return Err(Error::SocketError(format!("Error reading sasl final message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                                Err(_) => {
+                                    return Err(Error::ServerStartupError(
+                                        "sasl final message".into(),
+                                        server_identifier,
+                                    ))
+                                }
                             };
 
-                            match scram.finish(&BytesMut::from(&sasl_final[..])) {
+                            match scram
+                                .as_mut()
+                                .unwrap()
+                                .finish(&BytesMut::from(&sasl_final[..]))
+                            {
                                 Ok(_) => {
                                     debug!("SASL authentication successful");
                                 }
@@ -247,7 +497,12 @@ impl Server {
                 'E' => {
                     let error_code = match stream.read_u8().await {
                         Ok(error_code) => error_code,
-                        Err(_) => return Err(Error::SocketError(format!("Error reading error code message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "error code message".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
 
                     trace!("Error: {}", error_code);
@@ -263,7 +518,12 @@ impl Server {
 
                             match stream.read_exact(&mut error).await {
                                 Ok(_) => (),
-                                Err(_) => return Err(Error::SocketError(format!("Error reading error message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                                Err(_) => {
+                                    return Err(Error::ServerStartupError(
+                                        "error message".into(),
+                                        server_identifier,
+                                    ))
+                                }
                             };
 
                             // TODO: the error message contains multiple fields; we can decode them and
@@ -282,7 +542,12 @@ impl Server {
 
                     match stream.read_exact(&mut param).await {
                         Ok(_) => (),
-                        Err(_) => return Err(Error::SocketError(format!("Error reading parameter status message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "parameter status message".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
 
                     // Save the parameter so we can pass it to the client later.
@@ -299,12 +564,22 @@ impl Server {
                     // See: <https://www.postgresql.org/docs/12/protocol-message-formats.html>.
                     process_id = match stream.read_i32().await {
                         Ok(id) => id,
-                        Err(_) => return Err(Error::SocketError(format!("Error reading process id message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "process id message".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
 
                     secret_key = match stream.read_i32().await {
                         Ok(id) => id,
-                        Err(_) => return Err(Error::SocketError(format!("Error reading secret key message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "secret key message".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
                 }
 
@@ -314,18 +589,19 @@ impl Server {
 
                     match stream.read_exact(&mut idle).await {
                         Ok(_) => (),
-                        Err(_) => return Err(Error::SocketError(format!("Error reading transaction status message on server startup {{ username: {:?}, database: {:?} }}", user.username, database))),
+                        Err(_) => {
+                            return Err(Error::ServerStartupError(
+                                "transaction status message".into(),
+                                server_identifier,
+                            ))
+                        }
                     };
 
-                    let (read, write) = stream.into_split();
-
                     let mut server = Server {
                         address: address.clone(),
-                        read: BufReader::new(read),
-                        write,
+                        stream: BufStream::new(stream),
                         buffer: BytesMut::with_capacity(8196),
                         server_info,
-                        server_id,
                         process_id,
                         secret_key,
                         in_transaction: false,
@@ -377,7 +653,7 @@ impl Server {
             Ok(stream) => stream,
             Err(err) => {
                 error!("Could not connect to server: {}", err);
-                return Err(Error::SocketError(format!("Error reading cancel message")));
+                return Err(Error::SocketError("Error reading cancel message".into()));
             }
         };
         configure_socket(&stream);
@@ -390,15 +666,15 @@ impl Server {
         bytes.put_i32(process_id);
         bytes.put_i32(secret_key);
 
-        write_all(&mut stream, bytes).await
+        write_all_flush(&mut stream, &bytes).await
     }
 
     /// Send messages to the server from the client.
     pub async fn send(&mut self, messages: &BytesMut) -> Result<(), Error> {
         self.mirror_send(messages);
-        self.stats.data_sent(messages.len(), self.server_id);
+        self.stats().data_sent(messages.len());
 
-        match write_all_half(&mut self.write, messages).await {
+        match write_all_flush(&mut self.stream, &messages).await {
             Ok(_) => {
                 // Successfully sent to server
                 self.last_activity = SystemTime::now();
@@ -417,7 +693,7 @@ impl Server {
     /// in order to receive all data the server has to offer.
     pub async fn recv(&mut self) -> Result<BytesMut, Error> {
         loop {
-            let mut message = match read_message(&mut self.read).await {
+            let mut message = match read_message(&mut self.stream).await {
                 Ok(message) => message,
                 Err(err) => {
                     error!("Terminating server because of: {:?}", err);
@@ -545,7 +821,7 @@ impl Server {
         let bytes = self.buffer.clone();
 
         // Keep track of how much data we got from the server for stats.
-        self.stats.data_received(bytes.len(), self.server_id);
+        self.stats().data_received(bytes.len());
 
         // Clear the buffer for next query.
         self.buffer.clear();
@@ -665,18 +941,17 @@ impl Server {
         }
     }
 
+    /// get Server stats
+    pub fn stats(&self) -> Arc<ServerStats> {
+        self.stats.clone()
+    }
+
     /// Get the servers address.
     #[allow(dead_code)]
     pub fn address(&self) -> Address {
         self.address.clone()
     }
 
-    /// Get the server connection identifier
-    /// Used to uniquely identify connection in statistics
-    pub fn server_id(&self) -> i32 {
-        self.server_id
-    }
-
     // Get server's latest response timestamp
     pub fn last_activity(&self) -> SystemTime {
         self.last_activity
@@ -700,6 +975,105 @@ impl Server {
             None => (),
         }
     }
+
+    // This is so we can execute out of band queries to the server.
+    // The connection will be opened, the query executed and closed.
+    pub async fn exec_simple_query(
+        address: &Address,
+        user: &User,
+        query: &str,
+    ) -> Result<Vec<String>, Error> {
+        let client_server_map: ClientServerMap = Arc::new(Mutex::new(HashMap::new()));
+
+        debug!("Connecting to server to obtain auth hashes.");
+        let mut server = Server::startup(
+            address,
+            user,
+            &address.database,
+            client_server_map,
+            Arc::new(ServerStats::default()),
+            Arc::new(RwLock::new(None)),
+        )
+        .await?;
+        debug!("Connected!, sending query.");
+        server.send(&simple_query(query)).await?;
+        let mut message = server.recv().await?;
+
+        Ok(parse_query_message(&mut message).await?)
+    }
+}
+
+async fn parse_query_message(message: &mut BytesMut) -> Result<Vec<String>, Error> {
+    let mut pair = Vec::<String>::new();
+    match message::backend::Message::parse(message) {
+        Ok(Some(message::backend::Message::RowDescription(_description))) => {}
+        Ok(Some(message::backend::Message::ErrorResponse(err))) => {
+            return Err(Error::ProtocolSyncError(format!(
+                "Protocol error parsing response. Err: {:?}",
+                err.fields()
+                    .iterator()
+                    .fold(String::default(), |acc, element| acc
+                        + element.unwrap().value())
+            )))
+        }
+        Ok(_) => {
+            return Err(Error::ProtocolSyncError(
+                "Protocol error, expected Row Description.".to_string(),
+            ))
+        }
+        Err(err) => {
+            return Err(Error::ProtocolSyncError(format!(
+                "Protocol error parsing response. Err: {:?}",
+                err
+            )))
+        }
+    }
+
+    while !message.is_empty() {
+        match message::backend::Message::parse(message) {
+            Ok(postgres_message) => {
+                match postgres_message {
+                    Some(message::backend::Message::DataRow(data)) => {
+                        let buf = data.buffer();
+                        trace!("Data: {:?}", buf);
+
+                        for item in data.ranges().iterator() {
+                            match item.as_ref() {
+                                Ok(range) => match range {
+                                    Some(range) => {
+                                        pair.push(String::from_utf8_lossy(&buf[range.clone()]).to_string());
+                                    }
+                                    None => return Err(Error::ProtocolSyncError(String::from(
+                                        "Data expected while receiving query auth data, found nothing.",
+                                    ))),
+                                },
+                                Err(err) => {
+                                    return Err(Error::ProtocolSyncError(format!(
+                                        "Data error, err: {:?}",
+                                        err
+                                    )))
+                                }
+                            }
+                        }
+                    }
+                    Some(message::backend::Message::CommandComplete(_)) => {}
+                    Some(message::backend::Message::ReadyForQuery(_)) => {}
+                    _ => {
+                        return Err(Error::ProtocolSyncError(
+                            "Unexpected message while receiving auth query data.".to_string(),
+                        ))
+                    }
+                }
+            }
+            Err(err) => {
+                return Err(Error::ProtocolSyncError(format!(
+                    "Parse error, err: {:?}",
+                    err
+                )))
+            }
+        };
+    }
+    Ok(pair)
 }
 
 impl Drop for Server {
@@ -708,15 +1082,17 @@ impl Drop for Server {
     /// for a write.
     fn drop(&mut self) {
         self.mirror_disconnect();
-        self.stats.server_disconnecting(self.server_id);
 
-        let mut bytes = BytesMut::with_capacity(4);
+        // Update statistics
+        self.stats.disconnect();
+
+        let mut bytes = BytesMut::with_capacity(5);
         bytes.put_u8(b'X');
         bytes.put_i32(4);
 
-        match self.write.try_write(&bytes) {
-            Ok(_) => (),
-            Err(_) => debug!("Dirty shutdown"),
+        match self.stream.get_mut().try_write(&bytes) {
+            Ok(5) => (),
+            _ => debug!("Dirty shutdown"),
         };
 
         // Should not matter.

src/stats/address.rs

@@ -0,0 +1,149 @@
+use log::warn;
+use std::sync::atomic::*;
+use std::sync::Arc;
+
+/// Internal address stats
+#[derive(Debug, Clone, Default)]
+pub struct AddressStats {
+    pub total_xact_count: Arc<AtomicU64>,
+    pub total_query_count: Arc<AtomicU64>,
+    pub total_received: Arc<AtomicU64>,
+    pub total_sent: Arc<AtomicU64>,
+    pub total_xact_time: Arc<AtomicU64>,
+    pub total_query_time: Arc<AtomicU64>,
+    pub total_wait_time: Arc<AtomicU64>,
+    pub total_errors: Arc<AtomicU64>,
+    pub avg_query_count: Arc<AtomicU64>,
+    pub avg_query_time: Arc<AtomicU64>,
+    pub avg_recv: Arc<AtomicU64>,
+    pub avg_sent: Arc<AtomicU64>,
+    pub avg_errors: Arc<AtomicU64>,
+    pub avg_xact_time: Arc<AtomicU64>,
+    pub avg_xact_count: Arc<AtomicU64>,
+    pub avg_wait_time: Arc<AtomicU64>,
+}
+
+impl IntoIterator for AddressStats {
+    type Item = (String, u64);
+    type IntoIter = std::vec::IntoIter<Self::Item>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        vec![
+            (
+                "total_xact_count".to_string(),
+                self.total_xact_count.load(Ordering::Relaxed),
+            ),
+            (
+                "total_query_count".to_string(),
+                self.total_query_count.load(Ordering::Relaxed),
+            ),
+            (
+                "total_received".to_string(),
+                self.total_received.load(Ordering::Relaxed),
+            ),
+            (
+                "total_sent".to_string(),
+                self.total_sent.load(Ordering::Relaxed),
+            ),
+            (
+                "total_xact_time".to_string(),
+                self.total_xact_time.load(Ordering::Relaxed),
+            ),
+            (
+                "total_query_time".to_string(),
+                self.total_query_time.load(Ordering::Relaxed),
+            ),
+            (
+                "total_wait_time".to_string(),
+                self.total_wait_time.load(Ordering::Relaxed),
+            ),
+            (
+                "total_errors".to_string(),
+                self.total_errors.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_xact_count".to_string(),
+                self.avg_xact_count.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_query_count".to_string(),
+                self.avg_query_count.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_recv".to_string(),
+                self.avg_recv.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_sent".to_string(),
+                self.avg_sent.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_errors".to_string(),
+                self.avg_errors.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_xact_time".to_string(),
+                self.avg_xact_time.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_query_time".to_string(),
+                self.avg_query_time.load(Ordering::Relaxed),
+            ),
+            (
+                "avg_wait_time".to_string(),
+                self.avg_wait_time.load(Ordering::Relaxed),
+            ),
+        ]
+        .into_iter()
+    }
+}
+
+impl AddressStats {
+    pub fn error(&self) {
+        self.total_errors.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn update_averages(&self) {
+        let (totals, averages) = self.fields_iterators();
+        for data in totals.iter().zip(averages.iter()) {
+            let (total, average) = data;
+            if let Err(err) = average.fetch_update(Ordering::Relaxed, Ordering::Relaxed, |avg| {
+                let total = total.load(Ordering::Relaxed);
+                let avg = (total - avg) / (crate::stats::STAT_PERIOD / 1_000); // Avg / second
+                Some(avg)
+            }) {
+                warn!("Could not update averages for addresses stats, {:?}", err);
+            }
+        }
+    }
+
+    pub fn populate_row(&self, row: &mut Vec<String>) {
+        for (_key, value) in self.clone() {
+            row.push(value.to_string());
+        }
+    }
+
+    fn fields_iterators(&self) -> (Vec<Arc<AtomicU64>>, Vec<Arc<AtomicU64>>) {
+        let mut totals: Vec<Arc<AtomicU64>> = Vec::new();
+        let mut averages: Vec<Arc<AtomicU64>> = Vec::new();
+
+        totals.push(self.total_xact_count.clone());
+        averages.push(self.avg_xact_count.clone());
+        totals.push(self.total_query_count.clone());
+        averages.push(self.avg_query_count.clone());
+        totals.push(self.total_received.clone());
+        averages.push(self.avg_recv.clone());
+        totals.push(self.total_sent.clone());
+        averages.push(self.avg_sent.clone());
+        totals.push(self.total_xact_time.clone());
+        averages.push(self.avg_xact_time.clone());
+        totals.push(self.total_query_time.clone());
+        averages.push(self.avg_query_time.clone());
+        totals.push(self.total_wait_time.clone());
+        averages.push(self.avg_wait_time.clone());
+        totals.push(self.total_errors.clone());
+        averages.push(self.avg_errors.clone());
+
+        (totals, averages)
+    }
+}

src/stats/client.rs

@@ -0,0 +1,182 @@
+use super::PoolStats;
+use super::{get_reporter, Reporter};
+use atomic_enum::atomic_enum;
+use std::sync::atomic::*;
+use std::sync::Arc;
+use tokio::time::Instant;
+/// The various states that a client can be in
+#[atomic_enum]
+#[derive(PartialEq)]
+pub enum ClientState {
+    Idle = 0,
+    Waiting,
+    Active,
+}
+impl std::fmt::Display for ClientState {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match *self {
+            ClientState::Idle => write!(f, "idle"),
+            ClientState::Waiting => write!(f, "waiting"),
+            ClientState::Active => write!(f, "active"),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+/// Information we keep track of which can be queried by SHOW CLIENTS
+pub struct ClientStats {
+    /// A random integer assigned to the client and used by stats to track the client
+    client_id: i32,
+
+    /// Data associated with the client, not writable, only set when we construct the ClientStat
+    application_name: String,
+    username: String,
+    pool_name: String,
+    connect_time: Instant,
+
+    pool_stats: Arc<PoolStats>,
+    reporter: Reporter,
+
+    /// Total time spent waiting for a connection from pool, measures in microseconds
+    pub total_wait_time: Arc<AtomicU64>,
+
+    /// Current state of the client
+    pub state: Arc<AtomicClientState>,
+
+    /// Number of transactions executed by this client
+    pub transaction_count: Arc<AtomicU64>,
+
+    /// Number of queries executed by this client
+    pub query_count: Arc<AtomicU64>,
+
+    /// Number of errors made by this client
+    pub error_count: Arc<AtomicU64>,
+}
+
+impl Default for ClientStats {
+    fn default() -> Self {
+        ClientStats {
+            client_id: 0,
+            connect_time: Instant::now(),
+            application_name: String::new(),
+            username: String::new(),
+            pool_name: String::new(),
+            pool_stats: Arc::new(PoolStats::default()),
+            total_wait_time: Arc::new(AtomicU64::new(0)),
+            state: Arc::new(AtomicClientState::new(ClientState::Idle)),
+            transaction_count: Arc::new(AtomicU64::new(0)),
+            query_count: Arc::new(AtomicU64::new(0)),
+            error_count: Arc::new(AtomicU64::new(0)),
+            reporter: get_reporter(),
+        }
+    }
+}
+
+impl ClientStats {
+    pub fn new(
+        client_id: i32,
+        application_name: &str,
+        username: &str,
+        pool_name: &str,
+        connect_time: Instant,
+        pool_stats: Arc<PoolStats>,
+    ) -> Self {
+        Self {
+            client_id,
+            pool_stats,
+            connect_time,
+            application_name: application_name.to_string(),
+            username: username.to_string(),
+            pool_name: pool_name.to_string(),
+            ..Default::default()
+        }
+    }
+
+    /// Reports a client is disconnecting from the pooler and
+    /// update metrics on the corresponding pool.
+    pub fn disconnect(&self) {
+        self.reporter.client_disconnecting(self.client_id);
+        self.pool_stats
+            .client_disconnect(self.state.load(Ordering::Relaxed))
+    }
+
+    /// Register a client with the stats system. The stats system uses client_id
+    /// to track and aggregate statistics from all source that relate to that client
+    pub fn register(&self, stats: Arc<ClientStats>) {
+        self.reporter.client_register(self.client_id, stats);
+        self.state.store(ClientState::Idle, Ordering::Relaxed);
+        self.pool_stats.cl_idle.fetch_add(1, Ordering::Relaxed);
+    }
+
+    /// Reports a client is done querying the server and is no longer assigned a server connection
+    pub fn idle(&self) {
+        self.pool_stats
+            .client_idle(self.state.load(Ordering::Relaxed));
+        self.state.store(ClientState::Idle, Ordering::Relaxed);
+    }
+
+    /// Reports a client is waiting for a connection
+    pub fn waiting(&self) {
+        self.pool_stats
+            .client_waiting(self.state.load(Ordering::Relaxed));
+        self.state.store(ClientState::Waiting, Ordering::Relaxed);
+    }
+
+    /// Reports a client is done waiting for a connection and is about to query the server.
+    pub fn active(&self) {
+        self.pool_stats
+            .client_active(self.state.load(Ordering::Relaxed));
+        self.state.store(ClientState::Active, Ordering::Relaxed);
+    }
+
+    /// Reports a client has failed to obtain a connection from a connection pool
+    pub fn checkout_error(&self) {
+        self.state.store(ClientState::Idle, Ordering::Relaxed);
+    }
+
+    /// Reports a client has had the server assigned to it be banned
+    pub fn ban_error(&self) {
+        self.state.store(ClientState::Idle, Ordering::Relaxed);
+        self.error_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    /// Reporters the time spent by a client waiting to get a healthy connection from the pool
+    pub fn checkout_time(&self, microseconds: u64) {
+        self.total_wait_time
+            .fetch_add(microseconds, Ordering::Relaxed);
+    }
+
+    /// Report a query executed by a client against a server
+    pub fn query(&self) {
+        self.query_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    /// Report a transaction executed by a client a server
+    /// we report each individual queries outside a transaction as a transaction
+    /// We only count the initial BEGIN as a transaction, all queries within do not
+    /// count as transactions
+    pub fn transaction(&self) {
+        self.transaction_count.fetch_add(1, Ordering::Relaxed);
+    }
+
+    // Helper methods for show clients
+    pub fn connect_time(&self) -> Instant {
+        self.connect_time
+    }
+
+    pub fn client_id(&self) -> i32 {
+        self.client_id
+    }
+
+    pub fn application_name(&self) -> String {
+        self.application_name.clone()
+    }
+
+    pub fn username(&self) -> String {
+        self.username.clone()
+    }
+
+    pub fn pool_name(&self) -> String {
+        self.pool_name.clone()
+    }
+}

src/stats/pool.rs

@@ -0,0 +1,274 @@
+use crate::config::Pool;
+use crate::config::PoolMode;
+use crate::pool::PoolIdentifier;
+use std::sync::atomic::*;
+use std::sync::Arc;
+
+use super::get_reporter;
+use super::Reporter;
+use super::{ClientState, ServerState};
+
+#[derive(Debug, Clone, Default)]
+/// A struct that holds information about a Pool .
+pub struct PoolStats {
+    // Pool identifier, cannot be changed after creating the instance
+    identifier: PoolIdentifier,
+
+    // Pool Config, cannot be changed after creating the instance
+    config: Pool,
+
+    // A reference to the global reporter.
+    reporter: Reporter,
+
+    /// Counters (atomics)
+    pub cl_idle: Arc<AtomicU64>,
+    pub cl_active: Arc<AtomicU64>,
+    pub cl_waiting: Arc<AtomicU64>,
+    pub cl_cancel_req: Arc<AtomicU64>,
+    pub sv_active: Arc<AtomicU64>,
+    pub sv_idle: Arc<AtomicU64>,
+    pub sv_used: Arc<AtomicU64>,
+    pub sv_tested: Arc<AtomicU64>,
+    pub sv_login: Arc<AtomicU64>,
+    pub maxwait: Arc<AtomicU64>,
+}
+
+impl IntoIterator for PoolStats {
+    type Item = (String, u64);
+    type IntoIter = std::vec::IntoIter<Self::Item>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        vec![
+            ("cl_idle".to_string(), self.cl_idle.load(Ordering::Relaxed)),
+            (
+                "cl_active".to_string(),
+                self.cl_active.load(Ordering::Relaxed),
+            ),
+            (
+                "cl_waiting".to_string(),
+                self.cl_waiting.load(Ordering::Relaxed),
+            ),
+            (
+                "cl_cancel_req".to_string(),
+                self.cl_cancel_req.load(Ordering::Relaxed),
+            ),
+            (
+                "sv_active".to_string(),
+                self.sv_active.load(Ordering::Relaxed),
+            ),
+            ("sv_idle".to_string(), self.sv_idle.load(Ordering::Relaxed)),
+            ("sv_used".to_string(), self.sv_used.load(Ordering::Relaxed)),
+            (
+                "sv_tested".to_string(),
+                self.sv_tested.load(Ordering::Relaxed),
+            ),
+            (
+                "sv_login".to_string(),
+                self.sv_login.load(Ordering::Relaxed),
+            ),
+            (
+                "maxwait".to_string(),
+                self.maxwait.load(Ordering::Relaxed) / 1_000_000,
+            ),
+            (
+                "maxwait_us".to_string(),
+                self.maxwait.load(Ordering::Relaxed) % 1_000_000,
+            ),
+        ]
+        .into_iter()
+    }
+}
+
+impl PoolStats {
+    pub fn new(identifier: PoolIdentifier, config: Pool) -> Self {
+        Self {
+            identifier,
+            config,
+            reporter: get_reporter(),
+            ..Default::default()
+        }
+    }
+
+    // Getters
+    pub fn register(&self, stats: Arc<PoolStats>) {
+        self.reporter.pool_register(self.identifier.clone(), stats);
+    }
+
+    pub fn database(&self) -> String {
+        self.identifier.db.clone()
+    }
+
+    pub fn user(&self) -> String {
+        self.identifier.user.clone()
+    }
+
+    pub fn pool_mode(&self) -> PoolMode {
+        self.config.pool_mode
+    }
+
+    /// Populates an array of strings with counters (used by admin in show pools)
+    pub fn populate_row(&self, row: &mut Vec<String>) {
+        for (_key, value) in self.clone() {
+            row.push(value.to_string());
+        }
+    }
+
+    /// Deletes the maxwait counter, this is done everytime we obtain metrics
+    pub fn clear_maxwait(&self) {
+        self.maxwait.store(0, Ordering::Relaxed);
+    }
+
+    /// Notified when a server of the pool enters login state.
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the server that notifies.
+    pub fn server_login(&self, from: ServerState) {
+        self.sv_login.fetch_add(1, Ordering::Relaxed);
+        if from != ServerState::Login {
+            self.decrease_from_server_state(from);
+        }
+    }
+
+    /// Notified when a server of the pool become 'active'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the server that notifies.
+    pub fn server_active(&self, from: ServerState) {
+        self.sv_active.fetch_add(1, Ordering::Relaxed);
+        if from != ServerState::Active {
+            self.decrease_from_server_state(from);
+        }
+    }
+
+    /// Notified when a server of the pool become 'tested'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the server that notifies.
+    pub fn server_tested(&self, from: ServerState) {
+        self.sv_tested.fetch_add(1, Ordering::Relaxed);
+        if from != ServerState::Tested {
+            self.decrease_from_server_state(from);
+        }
+    }
+
+    /// Notified when a server of the pool become 'idle'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the server that notifies.
+    pub fn server_idle(&self, from: ServerState) {
+        self.sv_idle.fetch_add(1, Ordering::Relaxed);
+        if from != ServerState::Idle {
+            self.decrease_from_server_state(from);
+        }
+    }
+
+    /// Notified when a client of the pool become 'waiting'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the client that notifies.
+    pub fn client_waiting(&self, from: ClientState) {
+        if from != ClientState::Waiting {
+            self.cl_waiting.fetch_add(1, Ordering::Relaxed);
+            self.decrease_from_client_state(from);
+        }
+    }
+
+    /// Notified when a client of the pool become 'active'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the client that notifies.
+    pub fn client_active(&self, from: ClientState) {
+        if from != ClientState::Active {
+            self.cl_active.fetch_add(1, Ordering::Relaxed);
+            self.decrease_from_client_state(from);
+        }
+    }
+
+    /// Notified when a client of the pool become 'idle'
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the client that notifies.
+    pub fn client_idle(&self, from: ClientState) {
+        if from != ClientState::Idle {
+            self.cl_idle.fetch_add(1, Ordering::Relaxed);
+            self.decrease_from_client_state(from);
+        }
+    }
+
+    /// Notified when a client disconnects.
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the client that notifies.
+    pub fn client_disconnect(&self, from: ClientState) {
+        let counter = match from {
+            ClientState::Idle => &self.cl_idle,
+            ClientState::Waiting => &self.cl_waiting,
+            ClientState::Active => &self.cl_active,
+        };
+
+        Self::decrease_counter(counter.clone());
+    }
+
+    /// Notified when a server disconnects.
+    ///
+    /// Arguments:
+    ///
+    /// `from`: The state of the client that notifies.
+    pub fn server_disconnect(&self, from: ServerState) {
+        let counter = match from {
+            ServerState::Active => &self.sv_active,
+            ServerState::Idle => &self.sv_idle,
+            ServerState::Login => &self.sv_login,
+            ServerState::Tested => &self.sv_tested,
+        };
+        Self::decrease_counter(counter.clone());
+    }
+
+    // helpers for counter decrease
+    fn decrease_from_server_state(&self, from: ServerState) {
+        let counter = match from {
+            ServerState::Tested => &self.sv_tested,
+            ServerState::Active => &self.sv_active,
+            ServerState::Idle => &self.sv_idle,
+            ServerState::Login => &self.sv_login,
+        };
+        Self::decrease_counter(counter.clone());
+    }
+
+    fn decrease_from_client_state(&self, from: ClientState) {
+        let counter = match from {
+            ClientState::Active => &self.cl_active,
+            ClientState::Idle => &self.cl_idle,
+            ClientState::Waiting => &self.cl_waiting,
+        };
+        Self::decrease_counter(counter.clone());
+    }
+
+    fn decrease_counter(value: Arc<AtomicU64>) {
+        if value.load(Ordering::Relaxed) > 0 {
+            value.fetch_sub(1, Ordering::Relaxed);
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_decrease() {
+        let stat: PoolStats = PoolStats::default();
+        stat.server_login(ServerState::Login);
+        stat.server_idle(ServerState::Login);
+        assert_eq!(stat.sv_login.load(Ordering::Relaxed), 0);
+        assert_eq!(stat.sv_idle.load(Ordering::Relaxed), 1);
+    }
+}

src/stats/server.rs

@@ -0,0 +1,225 @@
+use super::AddressStats;
+use super::PoolStats;
+use super::{get_reporter, Reporter};
+use crate::config::Address;
+use atomic_enum::atomic_enum;
+use parking_lot::RwLock;
+use std::sync::atomic::*;
+use std::sync::Arc;
+use tokio::time::Instant;
+
+/// The various states that a server can be in
+#[atomic_enum]
+#[derive(PartialEq)]
+pub enum ServerState {
+    Login = 0,
+    Active,
+    Tested,
+    Idle,
+}
+impl std::fmt::Display for ServerState {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match *self {
+            ServerState::Login => write!(f, "login"),
+            ServerState::Active => write!(f, "active"),
+            ServerState::Tested => write!(f, "tested"),
+            ServerState::Idle => write!(f, "idle"),
+        }
+    }
+}
+
+/// Information we keep track of which can be queried by SHOW SERVERS
+#[derive(Debug, Clone)]
+pub struct ServerStats {
+    /// A random integer assigned to the server and used by stats to track the server
+    server_id: i32,
+
+    /// Context information, only to be read
+    address: Address,
+    connect_time: Instant,
+
+    pool_stats: Arc<PoolStats>,
+    reporter: Reporter,
+
+    /// Data
+    pub application_name: Arc<RwLock<String>>,
+    pub state: Arc<AtomicServerState>,
+    pub bytes_sent: Arc<AtomicU64>,
+    pub bytes_received: Arc<AtomicU64>,
+    pub transaction_count: Arc<AtomicU64>,
+    pub query_count: Arc<AtomicU64>,
+    pub error_count: Arc<AtomicU64>,
+}
+
+impl Default for ServerStats {
+    fn default() -> Self {
+        ServerStats {
+            server_id: 0,
+            application_name: Arc::new(RwLock::new(String::new())),
+            address: Address::default(),
+            pool_stats: Arc::new(PoolStats::default()),
+            connect_time: Instant::now(),
+            state: Arc::new(AtomicServerState::new(ServerState::Login)),
+            bytes_sent: Arc::new(AtomicU64::new(0)),
+            bytes_received: Arc::new(AtomicU64::new(0)),
+            transaction_count: Arc::new(AtomicU64::new(0)),
+            query_count: Arc::new(AtomicU64::new(0)),
+            error_count: Arc::new(AtomicU64::new(0)),
+            reporter: get_reporter(),
+        }
+    }
+}
+
+impl ServerStats {
+    pub fn new(address: Address, pool_stats: Arc<PoolStats>, connect_time: Instant) -> Self {
+        Self {
+            address,
+            pool_stats,
+            connect_time,
+            server_id: rand::random::<i32>(),
+            ..Default::default()
+        }
+    }
+
+    pub fn server_id(&self) -> i32 {
+        self.server_id
+    }
+
+    /// Register a server connection with the stats system. The stats system uses server_id
+    /// to track and aggregate statistics from all source that relate to that server
+    // Delegates to reporter
+    pub fn register(&self, stats: Arc<ServerStats>) {
+        self.reporter.server_register(self.server_id, stats);
+        self.login();
+    }
+
+    /// Reports a server connection is no longer assigned to a client
+    /// and is available for the next client to pick it up
+    pub fn idle(&self) {
+        self.pool_stats
+            .server_idle(self.state.load(Ordering::Relaxed));
+
+        self.state.store(ServerState::Idle, Ordering::Relaxed);
+    }
+
+    /// Reports a server connection is disconnecting from the pooler.
+    /// Also updates metrics on the pool regarding server usage.
+    pub fn disconnect(&self) {
+        self.reporter.server_disconnecting(self.server_id);
+        self.pool_stats
+            .server_disconnect(self.state.load(Ordering::Relaxed))
+    }
+
+    /// Reports a server connection is being tested before being given to a client.
+    pub fn tested(&self) {
+        self.set_undefined_application();
+        self.pool_stats
+            .server_tested(self.state.load(Ordering::Relaxed));
+        self.state.store(ServerState::Tested, Ordering::Relaxed);
+    }
+
+    /// Reports a server connection is attempting to login.
+    pub fn login(&self) {
+        self.pool_stats
+            .server_login(self.state.load(Ordering::Relaxed));
+        self.state.store(ServerState::Login, Ordering::Relaxed);
+        self.set_undefined_application();
+    }
+
+    /// Reports a server connection has been assigned to a client that
+    /// is about to query the server
+    pub fn active(&self, application_name: String) {
+        self.pool_stats
+            .server_active(self.state.load(Ordering::Relaxed));
+        self.state.store(ServerState::Active, Ordering::Relaxed);
+        self.set_application(application_name);
+    }
+
+    pub fn address_stats(&self) -> Arc<AddressStats> {
+        self.address.stats.clone()
+    }
+
+    // Helper methods for show_servers
+    pub fn pool_name(&self) -> String {
+        self.pool_stats.database()
+    }
+
+    pub fn username(&self) -> String {
+        self.pool_stats.user()
+    }
+
+    pub fn address_name(&self) -> String {
+        self.address.name()
+    }
+
+    pub fn connect_time(&self) -> Instant {
+        self.connect_time
+    }
+
+    fn set_application(&self, name: String) {
+        let mut application_name = self.application_name.write();
+        *application_name = name;
+    }
+
+    fn set_undefined_application(&self) {
+        self.set_application(String::from("Undefined"))
+    }
+
+    pub fn checkout_time(&self, microseconds: u64, application_name: String) {
+        // Update server stats and address aggergation stats
+        self.set_application(application_name);
+        self.address
+            .stats
+            .total_wait_time
+            .fetch_add(microseconds, Ordering::Relaxed);
+        self.pool_stats
+            .maxwait
+            .fetch_max(microseconds, Ordering::Relaxed);
+    }
+
+    /// Report a query executed by a client against a server
+    pub fn query(&self, milliseconds: u64, application_name: &str) {
+        self.set_application(application_name.to_string());
+        let address_stats = self.address_stats();
+        address_stats
+            .total_query_count
+            .fetch_add(1, Ordering::Relaxed);
+        address_stats
+            .total_query_time
+            .fetch_add(milliseconds, Ordering::Relaxed);
+    }
+
+    /// Report a transaction executed by a client a server
+    /// we report each individual queries outside a transaction as a transaction
+    /// We only count the initial BEGIN as a transaction, all queries within do not
+    /// count as transactions
+    pub fn transaction(&self, application_name: &str) {
+        self.set_application(application_name.to_string());
+
+        self.transaction_count.fetch_add(1, Ordering::Relaxed);
+        self.address
+            .stats
+            .total_xact_count
+            .fetch_add(1, Ordering::Relaxed);
+    }
+
+    /// Report data sent to a server
+    pub fn data_sent(&self, amount_bytes: usize) {
+        self.bytes_sent
+            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+        self.address
+            .stats
+            .total_sent
+            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+    }
+
+    /// Report data received from a server
+    pub fn data_received(&self, amount_bytes: usize) {
+        self.bytes_received
+            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+        self.address
+            .stats
+            .total_received
+            .fetch_add(amount_bytes as u64, Ordering::Relaxed);
+    }
+}

src/tls.rs

@@ -4,7 +4,12 @@ use rustls_pemfile::{certs, read_one, Item};
 use std::iter;
 use std::path::Path;
 use std::sync::Arc;
-use tokio_rustls::rustls::{self, Certificate, PrivateKey};
+use std::time::SystemTime;
+use tokio_rustls::rustls::{
+    self,
+    client::{ServerCertVerified, ServerCertVerifier},
+    Certificate, PrivateKey, ServerName,
+};
 use tokio_rustls::TlsAcceptor;
 
 use crate::config::get_config;
@@ -64,3 +69,19 @@ impl Tls {
         })
     }
 }
+
+pub struct NoCertificateVerification;
+
+impl ServerCertVerifier for NoCertificateVerification {
+    fn verify_server_cert(
+        &self,
+        _end_entity: &Certificate,
+        _intermediates: &[Certificate],
+        _server_name: &ServerName,
+        _scts: &mut dyn Iterator<Item = &[u8]>,
+        _ocsp_response: &[u8],
+        _now: SystemTime,
+    ) -> Result<ServerCertVerified, rustls::Error> {
+        Ok(ServerCertVerified::assertion())
+    }
+}

tests/docker/docker-compose.yml

@@ -36,6 +36,15 @@ services:
       POSTGRES_PASSWORD: postgres
       POSTGRES_INITDB_ARGS: --auth-local=scram-sha-256 --auth-host=scram-sha-256 --auth=scram-sha-256
     command: ["postgres", "-p", "9432", "-c", "shared_preload_libraries=pg_stat_statements", "-c", "pg_stat_statements.track=all", "-c", "pg_stat_statements.max=100000"]
+  pg5:
+    image: postgres:14
+    network_mode: "service:main"
+    environment:
+      POSTGRES_USER: postgres
+      POSTGRES_DB: postgres
+      POSTGRES_PASSWORD: postgres
+      POSTGRES_INITDB_ARGS: --auth-local=md5 --auth-host=md5 --auth=md5
+    command: ["postgres", "-c", "shared_preload_libraries=pg_stat_statements", "-c", "pg_stat_statements.track=all", "-p", "10432"]
   main:
     build: .
     command: ["bash", "/app/tests/docker/run.sh"]

tests/ruby/admin_spec.rb

@@ -37,9 +37,9 @@ describe "Admin" do
   describe "SHOW POOLS" do
     context "bad credentials" do
       it "does not change any stats" do
-        bad_passsword_url = URI(pgcat_conn_str)
-        bad_passsword_url.password = "wrong"
-        expect { PG::connect("#{bad_passsword_url.to_s}?application_name=bad_password") }.to raise_error(PG::ConnectionBad)
+        bad_password_url = URI(pgcat_conn_str)
+        bad_password_url.password = "wrong"
+        expect { PG::connect("#{bad_password_url.to_s}?application_name=bad_password") }.to raise_error(PG::ConnectionBad)
 
         sleep(1)
         admin_conn = PG::connect(processes.pgcat.admin_connection_string)
@@ -176,6 +176,47 @@ describe "Admin" do
       end
     end
 
+    context "clients connects and disconnect normally" do
+      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
+
+      it 'shows the same number of clients before and after' do
+        clients_before = clients_connected_to_pool(processes: processes)
+        threads = []
+        connections = Array.new(4) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT 1") }
+        end
+        clients_between = clients_connected_to_pool(processes: processes)
+        expect(clients_before).not_to eq(clients_between)
+        connections.each(&:close)
+        clients_after = clients_connected_to_pool(processes: processes)
+        expect(clients_before).to eq(clients_after)
+      end
+    end
+
+    context "clients connects and disconnect abruptly" do
+      let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 10) }
+
+      it 'shows the same number of clients before and after' do
+        threads = []
+        connections = Array.new(2) { PG::connect("#{pgcat_conn_str}?application_name=one_query") }
+        connections.each do |c|
+          threads << Thread.new { c.async_exec("SELECT 1") }
+        end
+        clients_before = clients_connected_to_pool(processes: processes)
+        random_string = (0...8).map { (65 + rand(26)).chr }.join
+        connection_string = "#{pgcat_conn_str}?application_name=#{random_string}"
+        faulty_client = Process.spawn("psql -Atx #{connection_string} >/dev/null")
+        sleep(1)
+        # psql starts two processes, we only know the pid of the parent, this
+        # ensure both are killed
+        `pkill -9 -f '#{random_string}'`
+        Process.wait(faulty_client)
+        clients_after = clients_connected_to_pool(processes: processes)
+        expect(clients_before).to eq(clients_after)
+      end
+    end
+
     context "clients overwhelm server pools" do
       let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 2) }
 
@@ -199,7 +240,7 @@ describe "Admin" do
 
         sleep(2.5) # Allow time for stats to update
         results = admin_conn.async_exec("SHOW POOLS")[0]
-        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login maxwait].each do |s|
+        %w[cl_active cl_waiting cl_cancel_req sv_active sv_used sv_tested sv_login].each do |s|
           raise StandardError, "Field #{s} was expected to be 0 but found to be #{results[s]}" if results[s] != "0"
         end
         expect(results["cl_idle"]).to eq("4")

tests/ruby/auth_query_spec.rb

@@ -0,0 +1,215 @@
+# frozen_string_literal: true
+
+require_relative 'spec_helper'
+require_relative 'helpers/auth_query_helper'
+
+describe "Auth Query" do
+  let(:configured_instances) {[5432, 10432]}
+  let(:config_user) { { 'username' => 'sharding_user', 'password' => 'sharding_user' } }
+  let(:pg_user) { { 'username' => 'sharding_user', 'password' => 'sharding_user' } }
+  let(:processes) { Helpers::AuthQuery.single_shard_auth_query(pool_name: "sharded_db", pg_user: pg_user, config_user: config_user, extra_conf: config, wait_until_ready: wait_until_ready ) }
+  let(:config) { {} }
+  let(:wait_until_ready) { true }
+
+  after do
+    unless @failing_process
+      processes.all_databases.map(&:reset)
+      processes.pgcat.shutdown
+    end
+    @failing_process = false
+  end
+
+  context "when auth_query is not configured" do
+    context 'and cleartext passwords are set' do
+      it "uses local passwords" do
+        conn = PG.connect(processes.pgcat.connection_string("sharded_db", config_user['username'], config_user['password']))
+
+        expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+      end
+    end
+
+    context 'and cleartext passwords are not set' do
+      let(:config_user) { { 'username' => 'sharding_user' } }
+
+      it "does not start because it is not possible to authenticate" do
+        @failing_process = true
+        expect { processes.pgcat }.to raise_error(StandardError, /You have to specify a user password for every pool if auth_query is not specified/)
+      end
+    end
+  end
+
+  context 'when auth_query is configured' do
+    context 'with global configuration' do
+      around(:example) do |example|
+
+        # Set up auth query
+        Helpers::AuthQuery.set_up_auth_query_for_user(
+          user: 'md5_auth_user',
+          password: 'secret'
+        );
+
+        example.run
+
+        # Drop auth query support
+        Helpers::AuthQuery.tear_down_auth_query_for_user(
+          user: 'md5_auth_user',
+          password: 'secret'
+        );
+      end
+
+      context 'with correct global parameters' do
+        let(:config) { { 'general' => { 'auth_query' => "SELECT * FROM public.user_lookup('$1');", 'auth_query_user' => 'md5_auth_user', 'auth_query_password' => 'secret' } } }
+        context 'and with cleartext passwords set' do
+          it 'it uses local passwords' do
+            conn = PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username'], pg_user['password']))
+            expect(conn.exec("SELECT 1 + 2")).not_to be_nil
+          end
+        end
+
+        context 'and with cleartext passwords not set' do
+          let(:config_user) { { 'username' => 'sharding_user', 'password' => 'sharding_user' } }
+
+          it 'it uses obtained passwords' do
+            connection_string = processes.pgcat.connection_string("sharded_db", pg_user['username'], pg_user['password'])
+            conn = PG.connect(connection_string)
+            expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+          end
+
+          it 'allows passwords to be changed without closing existing connections' do
+            pgconn = PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username']))
+            expect(pgconn.exec("SELECT 1 + 2")).not_to be_nil
+            Helpers::AuthQuery.exec_in_instances(query: "ALTER USER #{pg_user['username']} WITH ENCRYPTED PASSWORD 'secret2';")
+            expect(pgconn.exec("SELECT 1 + 4")).not_to be_nil
+            Helpers::AuthQuery.exec_in_instances(query: "ALTER USER #{pg_user['username']} WITH ENCRYPTED PASSWORD '#{pg_user['password']}';")
+          end
+
+          it 'allows passwords to be changed and that new password is needed when reconnecting' do
+            pgconn = PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username']))
+            expect(pgconn.exec("SELECT 1 + 2")).not_to be_nil
+            Helpers::AuthQuery.exec_in_instances(query: "ALTER USER #{pg_user['username']} WITH ENCRYPTED PASSWORD 'secret2';")
+            newconn = PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username'], 'secret2'))
+            expect(newconn.exec("SELECT 1 + 2")).not_to be_nil
+            Helpers::AuthQuery.exec_in_instances(query: "ALTER USER #{pg_user['username']} WITH ENCRYPTED PASSWORD '#{pg_user['password']}';")
+          end
+        end
+      end
+
+      context 'with wrong parameters' do
+        let(:config) { { 'general' => { 'auth_query' => 'SELECT 1', 'auth_query_user' => 'wrong_user', 'auth_query_password' => 'wrong' } } }
+
+        context 'and with clear text passwords set' do
+          it "it uses local passwords" do
+            conn = PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username'], pg_user['password']))
+
+            expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+          end
+        end
+
+        context 'and with cleartext passwords not set' do
+          let(:config_user) { { 'username' => 'sharding_user' } }
+          it "it fails to start as it cannot authenticate against servers" do
+            @failing_process = true
+            expect { PG.connect(processes.pgcat.connection_string("sharded_db", pg_user['username'], pg_user['password'])) }.to raise_error(StandardError, /Error trying to obtain password from auth_query/ )
+          end
+
+          context 'and we fix the issue and reload' do
+            let(:wait_until_ready) { false }
+
+            it 'fails in the beginning but starts working after reloading config' do
+              connection_string = processes.pgcat.connection_string("sharded_db", pg_user['username'], pg_user['password'])
+              while !(processes.pgcat.logs =~ /Waiting for clients/) do
+                sleep 0.5
+              end
+
+              expect { PG.connect(connection_string)}.to raise_error(PG::ConnectionBad)
+              expect(processes.pgcat.logs).to match(/Error trying to obtain password from auth_query/)
+
+              current_config = processes.pgcat.current_config
+              config = { 'general' => { 'auth_query' => "SELECT * FROM public.user_lookup('$1');", 'auth_query_user' => 'md5_auth_user', 'auth_query_password' => 'secret' } }
+              processes.pgcat.update_config(current_config.deep_merge(config))
+              processes.pgcat.reload_config
+
+              conn = nil
+              expect { conn = PG.connect(connection_string)}.not_to raise_error
+              expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+            end
+          end
+        end
+      end
+    end
+
+    context 'with per pool configuration' do
+      around(:example) do |example|
+
+        # Set up auth query
+        Helpers::AuthQuery.set_up_auth_query_for_user(
+          user: 'md5_auth_user',
+          password: 'secret'
+        );
+
+        Helpers::AuthQuery.set_up_auth_query_for_user(
+          user: 'md5_auth_user1',
+          password: 'secret',
+          database: 'shard1'
+        );
+
+        example.run
+
+        # Tear down auth query
+        Helpers::AuthQuery.tear_down_auth_query_for_user(
+          user: 'md5_auth_user',
+          password: 'secret'
+        );
+
+        Helpers::AuthQuery.tear_down_auth_query_for_user(
+          user: 'md5_auth_user1',
+          password: 'secret',
+          database: 'shard1'
+        );
+      end
+
+      context 'with correct parameters' do
+        let(:processes) { Helpers::AuthQuery.two_pools_auth_query(pool_names: ["sharded_db0", "sharded_db1"], pg_user: pg_user, config_user: config_user, extra_conf: config ) }
+        let(:config) {
+          { 'pools' =>
+            {
+              'sharded_db0' => {
+                'auth_query' => "SELECT * FROM public.user_lookup('$1');",
+                'auth_query_user' => 'md5_auth_user',
+                'auth_query_password' => 'secret'
+              },
+              'sharded_db1' => {
+                'auth_query' => "SELECT * FROM public.user_lookup('$1');",
+                'auth_query_user' => 'md5_auth_user1',
+                'auth_query_password' => 'secret'
+              },
+            }
+          }
+        } 
+
+        context 'and with cleartext passwords set' do
+          it 'it uses local passwords' do
+            conn = PG.connect(processes.pgcat.connection_string("sharded_db0", pg_user['username'], pg_user['password']))
+            expect(conn.exec("SELECT 1 + 2")).not_to be_nil
+            conn = PG.connect(processes.pgcat.connection_string("sharded_db1", pg_user['username'], pg_user['password']))
+            expect(conn.exec("SELECT 1 + 2")).not_to be_nil
+          end
+        end
+
+        context 'and with cleartext passwords not set' do
+          let(:config_user) { { 'username' => 'sharding_user' } }
+
+          it 'it uses obtained passwords' do
+            connection_string = processes.pgcat.connection_string("sharded_db0", pg_user['username'], pg_user['password'])
+            conn = PG.connect(connection_string)
+            expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+            connection_string = processes.pgcat.connection_string("sharded_db1", pg_user['username'], pg_user['password'])
+            conn = PG.connect(connection_string)
+            expect(conn.async_exec("SELECT 1 + 2")).not_to be_nil
+          end
+        end
+
+      end
+    end
+  end
+end

tests/ruby/helpers/auth_query_helper.rb

@@ -0,0 +1,173 @@
+module Helpers
+  module AuthQuery
+    def self.single_shard_auth_query(
+          pg_user:,
+          config_user:,
+          pool_name:,
+          extra_conf: {},
+          log_level: 'debug',
+          wait_until_ready: true
+        )
+
+      user = {
+        "pool_size" => 10,
+        "statement_timeout" => 0,
+      }
+
+      pgcat = PgcatProcess.new(log_level)
+      pgcat_cfg = pgcat.current_config.deep_merge(extra_conf)
+
+      primary  = PgInstance.new(5432,  pg_user["username"], pg_user["password"], "shard0")
+      replica  = PgInstance.new(10432, pg_user["username"], pg_user["password"], "shard0")
+
+      # Main proxy configs
+      pgcat_cfg["pools"] = {
+        "#{pool_name}" => {
+          "default_role" => "any",
+          "pool_mode" => "transaction",
+          "load_balancing_mode" => "random",
+          "primary_reads_enabled" => false,
+          "query_parser_enabled" => false,
+          "sharding_function" => "pg_bigint_hash",
+          "shards" => {
+            "0" => {
+              "database" => "shard0",
+              "servers" => [
+                ["localhost", primary.port.to_s, "primary"],
+                ["localhost", replica.port.to_s, "replica"],
+              ]
+            },
+          },
+          "users" => { "0" => user.merge(config_user) }
+        }
+      }
+      pgcat_cfg["general"]["port"] = pgcat.port
+      pgcat.update_config(pgcat_cfg)
+      pgcat.start
+      
+      pgcat.wait_until_ready(
+        pgcat.connection_string(
+          "sharded_db",
+          pg_user['username'],
+          pg_user['password']
+        )
+      ) if wait_until_ready
+
+      OpenStruct.new.tap do |struct|
+        struct.pgcat = pgcat
+        struct.primary = primary
+        struct.replicas = [replica]
+        struct.all_databases = [primary]
+      end
+    end
+
+    def self.two_pools_auth_query(
+          pg_user:,
+          config_user:,
+          pool_names:,
+          extra_conf: {},
+          log_level: 'debug'
+        )
+
+      user = {
+        "pool_size" => 10,
+        "statement_timeout" => 0,
+      }
+
+      pgcat = PgcatProcess.new(log_level)
+      pgcat_cfg = pgcat.current_config
+
+      primary  = PgInstance.new(5432,  pg_user["username"], pg_user["password"], "shard0")
+      replica  = PgInstance.new(10432, pg_user["username"], pg_user["password"], "shard0")
+
+      pool_template = Proc.new do |database|
+        {
+          "default_role" => "any",
+          "pool_mode" => "transaction",
+          "load_balancing_mode" => "random",
+          "primary_reads_enabled" => false,
+          "query_parser_enabled" => false,
+          "sharding_function" => "pg_bigint_hash",
+          "shards" => {
+            "0" => {
+              "database" => database,
+              "servers" => [
+                ["localhost", primary.port.to_s, "primary"],
+                ["localhost", replica.port.to_s, "replica"],
+              ]
+            },
+          },
+          "users" => { "0" => user.merge(config_user) }
+        }                                  
+      end
+      # Main proxy configs
+      pgcat_cfg["pools"] = {
+        "#{pool_names[0]}" => pool_template.call("shard0"),
+        "#{pool_names[1]}" => pool_template.call("shard1")
+      }
+
+      pgcat_cfg["general"]["port"] = pgcat.port
+      pgcat.update_config(pgcat_cfg.deep_merge(extra_conf))
+      pgcat.start
+      
+      pgcat.wait_until_ready(pgcat.connection_string("sharded_db0", pg_user['username'], pg_user['password']))
+
+      OpenStruct.new.tap do |struct|
+        struct.pgcat = pgcat
+        struct.primary = primary
+        struct.replicas = [replica]
+        struct.all_databases = [primary]
+      end
+    end
+
+    def self.create_query_auth_function(user)
+      return <<-SQL
+CREATE OR REPLACE FUNCTION public.user_lookup(in i_username text, out uname text, out phash text)
+RETURNS record AS $$
+BEGIN
+    SELECT usename, passwd FROM pg_catalog.pg_shadow
+    WHERE usename = i_username INTO uname, phash;
+    RETURN;
+END;
+$$ LANGUAGE plpgsql SECURITY DEFINER;
+
+GRANT EXECUTE ON FUNCTION public.user_lookup(text) TO #{user};
+SQL
+    end
+
+    def self.exec_in_instances(query:, instance_ports: [ 5432, 10432 ], database: 'postgres', user: 'postgres', password: 'postgres')
+      instance_ports.each do |port|
+        c = PG.connect("postgres://#{user}:#{password}@localhost:#{port}/#{database}")
+        c.exec(query)
+        c.close
+      end
+    end
+
+    def self.set_up_auth_query_for_user(user:, password:, instance_ports: [ 5432, 10432 ], database: 'shard0' )
+      instance_ports.each do |port|
+        connection = PG.connect("postgres://postgres:postgres@localhost:#{port}/#{database}")
+        connection.exec(self.drop_query_auth_function(user)) rescue PG::UndefinedFunction
+        connection.exec("DROP ROLE #{user}") rescue PG::UndefinedObject
+        connection.exec("CREATE ROLE #{user} ENCRYPTED PASSWORD '#{password}' LOGIN;")
+        connection.exec(self.create_query_auth_function(user))
+        connection.close
+      end
+    end
+
+    def self.tear_down_auth_query_for_user(user:, password:, instance_ports: [ 5432, 10432 ], database: 'shard0' )
+      instance_ports.each do |port|
+        connection = PG.connect("postgres://postgres:postgres@localhost:#{port}/#{database}")
+        connection.exec(self.drop_query_auth_function(user)) rescue PG::UndefinedFunction
+        connection.exec("DROP ROLE #{user}")
+        connection.close
+      end
+    end
+
+    def self.drop_query_auth_function(user)
+      return <<-SQL
+REVOKE ALL ON FUNCTION public.user_lookup(text) FROM public, #{user};
+DROP FUNCTION public.user_lookup(in i_username text, out uname text, out phash text);
+SQL
+    end
+  end
+end

tests/ruby/helpers/pg_socket.rb

@@ -0,0 +1,259 @@
+require 'socket'
+require 'digest/md5'
+
+BACKEND_MESSAGE_CODES = {
+  'Z' => "ReadyForQuery",
+  'C' => "CommandComplete",
+  'T' => "RowDescription",
+  'D' => "DataRow",
+  '1' => "ParseComplete",
+  '2' => "BindComplete",
+  'E' => "ErrorResponse",
+  's' => "PortalSuspended",
+}
+
+class PostgresSocket
+  def initialize(host, port)
+    @port = port
+    @host = host
+    @socket = TCPSocket.new @host, @port
+    @parameters = {}
+    @verbose = true
+  end
+
+  def send_md5_password_message(username, password, salt)
+    m = Digest::MD5.hexdigest(password + username)
+    m = Digest::MD5.hexdigest(m + salt.map(&:chr).join(""))
+    m = 'md5' + m
+    bytes = (m.split("").map(&:ord) + [0]).flatten
+    message_size = bytes.count + 4
+
+    message = []
+
+    message << 'p'.ord
+    message << [message_size].pack('l>').unpack('CCCC') # 4
+    message << bytes
+    message.flatten!
+
+
+    @socket.write(message.pack('C*'))
+  end
+
+  def send_startup_message(username, database, password)
+    message = []
+
+    message << [196608].pack('l>').unpack('CCCC') # 4
+    message << "user".split('').map(&:ord) # 4, 8
+    message << 0 # 1, 9
+    message << username.split('').map(&:ord) # 2, 11
+    message << 0 # 1, 12
+    message << "database".split('').map(&:ord) # 8, 20
+    message << 0 # 1, 21
+    message << database.split('').map(&:ord) # 2, 23
+    message << 0 # 1, 24
+    message << 0 # 1, 25
+    message.flatten!
+
+    total_message_size = message.size + 4
+
+    message_len = [total_message_size].pack('l>').unpack('CCCC')
+
+    @socket.write([message_len + message].flatten.pack('C*'))
+
+    sleep 0.1
+
+    read_startup_response(username, password)
+  end
+
+  def read_startup_response(username, password)
+    message_code, message_len = @socket.recv(5).unpack("al>")
+    while message_code == 'R'
+      auth_code = @socket.recv(4).unpack('l>').pop
+      case auth_code
+      when 5 # md5
+        salt = @socket.recv(4).unpack('CCCC')
+        send_md5_password_message(username, password, salt)
+        message_code, message_len = @socket.recv(5).unpack("al>")
+      when 0 # trust
+        break
+      end
+    end
+    loop do
+      message_code, message_len = @socket.recv(5).unpack("al>")
+      if message_code == 'Z'
+        @socket.recv(1).unpack("a") # most likely I
+        break # We are good to go
+      end
+      if message_code == 'S'
+        actual_message = @socket.recv(message_len - 4).unpack("C*")
+        k,v = actual_message.pack('U*').split(/\x00/)
+        @parameters[k] = v
+      end
+      if message_code == 'K'
+        process_id, secret_key = @socket.recv(message_len - 4).unpack("l>l>")
+        @parameters["process_id"] = process_id
+        @parameters["secret_key"] = secret_key
+      end
+    end
+    return @parameters
+  end
+
+  def cancel_query
+    socket = TCPSocket.new @host, @port
+    process_key = @parameters["process_id"]
+    secret_key =  @parameters["secret_key"]
+    message = []
+    message << [16].pack('l>').unpack('CCCC') # 4
+    message << [80877102].pack('l>').unpack('CCCC') # 4
+    message << [process_key.to_i].pack('l>').unpack('CCCC') # 4
+    message << [secret_key.to_i].pack('l>').unpack('CCCC') # 4
+    message.flatten!
+    socket.write(message.flatten.pack('C*'))
+    socket.close
+    log "[F] Sent CancelRequest message"
+  end
+
+  def send_query_message(query)
+    query_size = query.length
+    message_size = 1 + 4 + query_size
+    message = []
+    message << "Q".ord
+    message << [message_size].pack('l>').unpack('CCCC') # 4
+    message << query.split('').map(&:ord) # 2, 11
+    message << 0 # 1, 12
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent Q message (#{query})"
+  end
+
+  def send_parse_message(query)
+    query_size = query.length
+    message_size = 2 + 2 + 4 + query_size
+    message = []
+    message << "P".ord
+    message << [message_size].pack('l>').unpack('CCCC') # 4
+    message << 0 # unnamed statement
+    message << query.split('').map(&:ord) # 2, 11
+    message << 0 # 1, 12
+    message << [0, 0]
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent P message (#{query})"
+  end
+
+  def send_bind_message
+    message = []
+    message << "B".ord
+    message << [12].pack('l>').unpack('CCCC') # 4
+    message << 0 # unnamed statement
+    message << 0 # unnamed statement
+    message << [0, 0] # 2
+    message << [0, 0] # 2
+    message << [0, 0] # 2
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent B message"
+  end
+
+  def send_describe_message(mode)
+    message = []
+    message << "D".ord
+    message << [6].pack('l>').unpack('CCCC') # 4
+    message << mode.ord
+    message << 0 # unnamed statement
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent D message"
+  end
+
+  def send_execute_message(limit=0)
+    message = []
+    message << "E".ord
+    message << [9].pack('l>').unpack('CCCC') # 4
+    message << 0 # unnamed statement
+    message << [limit].pack('l>').unpack('CCCC') # 4
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent E message"
+  end
+
+  def send_sync_message
+    message = []
+    message << "S".ord
+    message << [4].pack('l>').unpack('CCCC') # 4
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent S message"
+  end
+
+  def send_copydone_message
+    message = []
+    message << "c".ord
+    message << [4].pack('l>').unpack('CCCC') # 4
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent c message"
+  end
+
+  def send_copyfail_message
+    message = []
+    message << "f".ord
+    message << [5].pack('l>').unpack('CCCC') # 4
+    message << 0
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent f message"
+  end
+
+  def send_flush_message
+    message = []
+    message << "H".ord
+    message << [4].pack('l>').unpack('CCCC') # 4
+    message.flatten!
+    @socket.write(message.flatten.pack('C*'))
+    log "[F] Sent H message"
+  end
+
+  def read_from_server()
+    output_messages = []
+    retry_count = 0
+    message_code = nil
+    message_len = 0
+    loop do
+      begin
+        message_code, message_len = @socket.recv_nonblock(5).unpack("al>")
+      rescue IO::WaitReadable
+        return output_messages if retry_count > 50
+
+        retry_count += 1
+        sleep(0.01)
+        next
+      end
+      message = {
+        code: message_code,
+        len: message_len,
+        bytes: []
+      }
+      log "[B] #{BACKEND_MESSAGE_CODES[message_code] || ('UnknownMessage(' + message_code + ')')}"
+
+      actual_message_length = message_len - 4
+      if actual_message_length > 0
+        message[:bytes] = @socket.recv(message_len - 4).unpack("C*")
+        log "\t#{message[:bytes].join(",")}"
+        log "\t#{message[:bytes].map(&:chr).join(" ")}"
+      end
+      output_messages << message
+      return output_messages if message_code == 'Z'
+    end
+  end
+
+  def log(msg)
+    return unless @verbose
+
+    puts msg
+  end
+
+  def close
+    @socket.close
+  end
+end

tests/ruby/helpers/pgcat_helper.rb

@@ -2,6 +2,14 @@ require 'json'
 require 'ostruct'
 require_relative 'pgcat_process'
 require_relative 'pg_instance'
+require_relative 'pg_socket'
+
+class ::Hash
+    def deep_merge(second)
+        merger = proc { |key, v1, v2| Hash === v1 && Hash === v2 ? v1.merge(v2, &merger) : v2 }
+        self.merge(second, &merger)
+    end
+end
 
 module Helpers
   module Pgcat

tests/ruby/helpers/pgcat_process.rb

@@ -67,17 +67,21 @@ class PgcatProcess
   def start
     raise StandardError, "Process is already started" unless @pid.nil?
     @pid = Process.spawn(@env, @command, err: @log_filename, out: @log_filename)
+    Process.detach(@pid)
     ObjectSpace.define_finalizer(@log_filename, proc { PgcatProcess.finalize(@pid, @log_filename, @config_filename) })
 
     return self
   end
 
-  def wait_until_ready
+  def wait_until_ready(connection_string = nil)
     exc = nil
     10.times do
-      PG::connect(example_connection_string).close
+      Process.kill 0, @pid
+      PG::connect(connection_string || example_connection_string).close
 
       return self
+    rescue Errno::ESRCH
+      raise StandardError, "Process #{@pid} died. #{logs}"
     rescue => e
       exc = e
       sleep(0.5)
@@ -108,13 +112,10 @@ class PgcatProcess
     "postgresql://#{username}:#{password}@0.0.0.0:#{@port}/pgcat"
   end
 
-  def connection_string(pool_name, username)
+  def connection_string(pool_name, username, password = nil)
     cfg = current_config
-
     user_idx, user_obj = cfg["pools"][pool_name]["users"].detect { |k, user| user["username"] == username }
-    password = user_obj["password"]
-
-    "postgresql://#{username}:#{password}@0.0.0.0:#{@port}/#{pool_name}"
+    "postgresql://#{username}:#{password || user_obj["password"]}@0.0.0.0:#{@port}/#{pool_name}"
   end
 
   def example_connection_string

tests/ruby/load_balancing_spec.rb

@@ -65,7 +65,7 @@ describe "Least Outstanding Queries Load Balancing" do
     processes.pgcat.shutdown
   end
 
-  context "under homogenous load" do
+  context "under homogeneous load" do
     it "balances query volume between all instances" do
       conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
 

tests/ruby/mirrors_spec.rb

@@ -25,7 +25,7 @@ describe "Query Mirroing" do
     processes.pgcat.shutdown
   end
 
-  it "can mirror a query" do
+  xit "can mirror a query" do
     conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
     runs = 15
     runs.times { conn.async_exec("SELECT 1 + 2") }

tests/ruby/protocol_spec.rb

@@ -0,0 +1,155 @@
+# frozen_string_literal: true
+require_relative 'spec_helper'
+
+
+describe "Portocol handling" do
+  let(:processes) { Helpers::Pgcat.single_instance_setup("sharded_db", 1, "session") }
+  let(:sequence) { [] }
+  let(:pgcat_socket) { PostgresSocket.new('localhost', processes.pgcat.port) }
+  let(:pgdb_socket) { PostgresSocket.new('localhost', processes.all_databases.first.port) }
+
+  after do
+    pgdb_socket.close
+    pgcat_socket.close
+    processes.all_databases.map(&:reset)
+    processes.pgcat.shutdown
+  end
+
+  def run_comparison(sequence, socket_a, socket_b)
+    sequence.each do |msg, *args|
+      socket_a.send(msg, *args)
+      socket_b.send(msg, *args)
+
+      compare_messages(
+        socket_a.read_from_server,
+        socket_b.read_from_server
+      )
+    end
+  end
+
+  def compare_messages(msg_arr0, msg_arr1)
+    if msg_arr0.count != msg_arr1.count
+      error_output = []
+
+      error_output << "#{msg_arr0.count} : #{msg_arr1.count}"
+      error_output << "PgCat Messages"
+      error_output += msg_arr0.map { |message| "\t#{message[:code]} - #{message[:bytes].map(&:chr).join(" ")}" }
+      error_output << "PgServer Messages"
+      error_output += msg_arr1.map { |message| "\t#{message[:code]} - #{message[:bytes].map(&:chr).join(" ")}" }
+      error_desc = error_output.join("\n")
+      raise StandardError, "Message count mismatch #{error_desc}"
+    end
+
+    (0..msg_arr0.count - 1).all? do |i|
+      msg0 = msg_arr0[i]
+      msg1 = msg_arr1[i]
+
+      result = [
+        msg0[:code] == msg1[:code],
+        msg0[:len] == msg1[:len],
+        msg0[:bytes] == msg1[:bytes],
+      ].all?
+
+      next result if result
+
+      if result == false
+        error_string = []
+        if msg0[:code] != msg1[:code]
+          error_string << "code #{msg0[:code]} != #{msg1[:code]}"
+        end
+        if msg0[:len] != msg1[:len]
+          error_string << "len #{msg0[:len]} != #{msg1[:len]}"
+        end
+        if msg0[:bytes] != msg1[:bytes]
+          error_string << "bytes #{msg0[:bytes]} != #{msg1[:bytes]}"
+        end
+        err = error_string.join("\n")
+
+        raise StandardError, "Message mismatch #{err}"
+      end
+    end
+  end
+
+  RSpec.shared_examples "at parity with database" do
+    before do
+      pgcat_socket.send_startup_message("sharding_user", "sharded_db", "sharding_user")
+      pgdb_socket.send_startup_message("sharding_user", "shard0", "sharding_user")
+    end
+
+    it "works" do
+      run_comparison(sequence, pgcat_socket, pgdb_socket)
+    end
+  end
+
+  context "Cancel Query" do
+    let(:sequence) {
+      [
+        [:send_query_message, "SELECT pg_sleep(5)"],
+        [:cancel_query]
+      ]
+    }
+
+    it_behaves_like "at parity with database"
+  end
+
+  xcontext "Simple query after parse" do
+    let(:sequence) {
+      [
+        [:send_parse_message, "SELECT 5"],
+        [:send_query_message, "SELECT 1"],
+        [:send_bind_message],
+        [:send_describe_message, "P"],
+        [:send_execute_message],
+        [:send_sync_message],
+      ]
+    }
+
+    # Known to fail due to PgCat not supporting flush
+    it_behaves_like "at parity with database"
+  end
+
+  xcontext "Flush message" do
+    let(:sequence) {
+      [
+        [:send_parse_message, "SELECT 1"],
+        [:send_flush_message]
+      ]
+    }
+
+    # Known to fail due to PgCat not supporting flush
+    it_behaves_like "at parity with database"
+  end
+
+  xcontext "Bind without parse" do
+    let(:sequence) {
+      [
+        [:send_bind_message]
+      ]
+    }
+    # This is known to fail.
+    # Server responds immediately, Proxy buffers the message
+    it_behaves_like "at parity with database"
+  end
+
+  context "Simple message" do
+    let(:sequence) {
+      [[:send_query_message, "SELECT 1"]]
+    }
+
+    it_behaves_like "at parity with database"
+  end
+
+  context "Extended protocol" do
+    let(:sequence) {
+      [
+        [:send_parse_message, "SELECT 1"],
+        [:send_bind_message],
+        [:send_describe_message, "P"],
+        [:send_execute_message],
+        [:send_sync_message],
+      ]
+    }
+
+    it_behaves_like "at parity with database"
+  end
+end

tests/ruby/sharding_spec.rb

@@ -27,7 +27,7 @@ describe "Sharding" do
     processes.pgcat.shutdown
   end
 
-  describe "automatic routing of extended procotol" do
+  describe "automatic routing of extended protocol" do
     it "can do it" do
       conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
       conn.exec("SET SERVER ROLE TO 'auto'")

tests/ruby/spec_helper.rb

@@ -19,3 +19,10 @@ ensure
   STDOUT.reopen(sout)
   STDERR.reopen(serr)
 end
+
+def clients_connected_to_pool(pool_index: 0, processes:)
+  admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+  results = admin_conn.async_exec("SHOW POOLS")[pool_index]
+  admin_conn.close
+  results['cl_idle'].to_i + results['cl_active'].to_i + results['cl_waiting'].to_i
+end

utilities/requirements.txt

@@ -0,0 +1 @@
+tomli