more lint changes

Authored-by: Javier Goday <jgoday@gmail.com>

.github/workflows/build-and-push.yaml

@@ -23,14 +23,17 @@ jobs:
 
     steps:
       - name: Checkout Repository
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v2
+        uses: docker/setup-buildx-action@v3
 
       - name: Determine tags
         id: metadata
-        uses: docker/metadata-action@v4
+        uses: docker/metadata-action@v5
         with:
           images: ${{ env.registry }}/${{ env.image-name }}
           tags: |
@@ -42,15 +45,18 @@ jobs:
             type=raw,value=latest,enable={{ is_default_branch }}
 
       - name: Log in to the Container registry
-        uses: docker/login-action@v2.1.0
+        uses: docker/login-action@v3
         with:
           registry: ${{ env.registry }}
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Build and push ${{ env.image-name }}
-        uses: docker/build-push-action@v3
+        uses: docker/build-push-action@v6
         with:
+          context: .
+          platforms: linux/amd64,linux/arm64
+          provenance: false
           push: true
           tags: ${{ steps.metadata.outputs.tags }}
           labels: ${{ steps.metadata.outputs.labels }}

Cargo.lock

@@ -146,6 +146,12 @@ dependencies = [
  "syn 2.0.26",
 ]
 
+[[package]]
+name = "atomic-waker"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1505bd5d3d116872e7271a6d4e16d81d0c8570876c8de68093a09ac269d8aac0"
+
 [[package]]
 name = "atomic_enum"
 version = "0.2.0"
@@ -542,29 +548,23 @@ checksum = "b6c80984affa11d98d1b88b66ac8853f143217b399d3c74116778ff8fdb4ed2e"
 
 [[package]]
 name = "h2"
-version = "0.3.20"
+version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97ec8491ebaf99c8eaa73058b045fe58073cd6be7f596ac993ced0b0a0c01049"
+checksum = "524e8ac6999421f49a846c2d4411f337e53497d8ec55d67753beffa43c5d9205"
 dependencies = [
+ "atomic-waker",
  "bytes",
  "fnv",
  "futures-core",
  "futures-sink",
- "futures-util",
  "http",
- "indexmap 1.9.3",
+ "indexmap",
  "slab",
  "tokio",
  "tokio-util",
  "tracing",
 ]
 
-[[package]]
-name = "hashbrown"
-version = "0.12.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
-
 [[package]]
 name = "hashbrown"
 version = "0.14.0"
@@ -609,9 +609,9 @@ dependencies = [
 
 [[package]]
 name = "http"
-version = "0.2.9"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd6effc99afb63425aff9b05836f029929e345a6148a14b7ecd5ab67af944482"
+checksum = "21b9ddb458710bc376481b842f5da65cdf31522de232c1ca8146abce2a358258"
 dependencies = [
  "bytes",
  "fnv",
@@ -620,12 +620,24 @@ dependencies = [
 
 [[package]]
 name = "http-body"
-version = "0.4.5"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d5f38f16d184e36f2408a55281cd658ecbd3ca05cce6d6510a176eca393e26d1"
+checksum = "1efedce1fb8e6913f23e0c92de8e62cd5b772a67e7b3946df930a62566c93184"
 dependencies = [
  "bytes",
  "http",
+]
+
+[[package]]
+name = "http-body-util"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "793429d76616a256bcb62c2a2ec2bed781c8307e797e2598c50010f2bee2544f"
+dependencies = [
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
  "pin-project-lite",
 ]
 
@@ -643,13 +655,12 @@ checksum = "c4a1e36c821dbe04574f602848a19f742f4fb3c98d40449f11bcad18d6b17421"
 
 [[package]]
 name = "hyper"
-version = "0.14.27"
+version = "1.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ffb1cfd654a8219eaef89881fdb3bb3b1cdc5fa75ded05d6933b2b382e395468"
+checksum = "50dfd22e0e76d0f662d429a5f80fcaf3855009297eab6a0a9f8543834744ba05"
 dependencies = [
  "bytes",
  "futures-channel",
- "futures-core",
  "futures-util",
  "h2",
  "http",
@@ -658,13 +669,26 @@ dependencies = [
  "httpdate",
  "itoa",
  "pin-project-lite",
- "socket2 0.4.9",
+ "smallvec",
  "tokio",
- "tower-service",
- "tracing",
  "want",
 ]
 
+[[package]]
+name = "hyper-util"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cde7055719c54e36e95e8719f95883f22072a48ede39db7fc17a4e1d5281e9b9"
+dependencies = [
+ "bytes",
+ "futures-util",
+ "http",
+ "http-body",
+ "hyper",
+ "pin-project-lite",
+ "tokio",
+]
+
 [[package]]
 name = "iana-time-zone"
 version = "0.1.57"
@@ -709,16 +733,6 @@ dependencies = [
  "unicode-normalization",
 ]
 
-[[package]]
-name = "indexmap"
-version = "1.9.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"
-dependencies = [
- "autocfg",
- "hashbrown 0.12.3",
-]
-
 [[package]]
 name = "indexmap"
 version = "2.0.0"
@@ -726,7 +740,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d5477fe2230a79769d8dc68e0eabf5437907c0457a5614a9e8dddb67f65eb65d"
 dependencies = [
  "equivalent",
- "hashbrown 0.14.0",
+ "hashbrown",
 ]
 
 [[package]]
@@ -848,7 +862,7 @@ version = "0.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1efa59af2ddfad1854ae27d75009d538d0998b4b2fd47083e743ac1a10e46c60"
 dependencies = [
- "hashbrown 0.14.0",
+ "hashbrown",
 ]
 
 [[package]]
@@ -1020,7 +1034,7 @@ checksum = "9b2a4787296e9989611394c33f193f676704af1686e70b8f8033ab5ba9a35a94"
 
 [[package]]
 name = "pgcat"
-version = "1.1.2-dev4"
+version = "1.2.0"
 dependencies = [
  "arc-swap",
  "async-trait",
@@ -1034,7 +1048,9 @@ dependencies = [
  "fallible-iterator",
  "futures",
  "hmac",
+ "http-body-util",
  "hyper",
+ "hyper-util",
  "itertools",
  "jemallocator",
  "log",
@@ -1478,9 +1494,9 @@ dependencies = [
 
 [[package]]
 name = "smallvec"
-version = "1.11.0"
+version = "1.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62bb4feee49fdd9f707ef802e22365a35de4b7b299de4763d44bfea899442ff9"
+checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
 
 [[package]]
 name = "socket2"
@@ -1510,9 +1526,9 @@ checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
 [[package]]
 name = "sqlparser"
-version = "0.34.0"
+version = "0.41.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37d3706eefb17039056234df6b566b0014f303f867f2656108334a55b8096f59"
+checksum = "5cc2c25a6c66789625ef164b4c7d2e548d627902280c13710d33da8222169964"
 dependencies = [
  "log",
  "sqlparser_derive",
@@ -1520,13 +1536,13 @@ dependencies = [
 
 [[package]]
 name = "sqlparser_derive"
-version = "0.1.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "55fe75cb4a364c7f7ae06c7dbbc8d84bddd85d6cdf9975963c3935bc1991761e"
+checksum = "01b2e185515564f15375f593fb966b5718bc624ba77fe49fa4616ad619690554"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 1.0.109",
+ "syn 2.0.26",
 ]
 
 [[package]]
@@ -1741,19 +1757,13 @@ version = "0.19.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f8123f27e969974a3dfba720fdb560be359f57b44302d280ba72e76a74480e8a"
 dependencies = [
- "indexmap 2.0.0",
+ "indexmap",
  "serde",
  "serde_spanned",
  "toml_datetime",
  "winnow",
 ]
 
-[[package]]
-name = "tower-service"
-version = "0.3.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b6bc1c9ce2b5135ac7f93c72918fc37feb872bdc6a5533a8b85eb4b86bfdae52"
-
 [[package]]
 name = "tracing"
 version = "0.1.37"

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "pgcat"
-version = "1.1.2-dev4"
+version = "1.2.0"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
@@ -19,7 +19,7 @@ serde_derive = "1"
 regex = "1"
 num_cpus = "1"
 once_cell = "1"
-sqlparser = {version = "0.34", features = ["visitor"] }
+sqlparser = { version = "0.41", features = ["visitor"] }
 log = "0.4"
 arc-swap = "1"
 parking_lot = "0.12.1"
@@ -29,7 +29,9 @@ base64 = "0.21"
 stringprep = "0.1"
 tokio-rustls = "0.24"
 rustls-pemfile = "1"
-hyper = { version = "0.14", features = ["full"] }
+http-body-util = "0.1.2"
+hyper = { version = "1.4.1", features = ["full"] }
+hyper-util = { version = "0.1.7", features = ["tokio"] }
 phf = { version = "0.11.1", features = ["macros"] }
 exitcode = "1.1.2"
 futures = "0.3"
@@ -47,9 +49,12 @@ serde_json = "1"
 itertools = "0.10"
 clap = { version = "4.3.1", features = ["derive", "env"] }
 tracing = "0.1.37"
-tracing-subscriber = { version = "0.3.17", features = ["json", "env-filter", "std"]}
+tracing-subscriber = { version = "0.3.17", features = [
+    "json",
+    "env-filter",
+    "std",
+] }
 lru = "0.12.0"
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 jemallocator = "0.5.0"
-

Dockerfile

@@ -1,4 +1,4 @@
-FROM rust:1-slim-bookworm AS builder
+FROM rust:1.79.0-slim-bookworm AS builder
 
 RUN apt-get update && \
     apt-get install -y build-essential
@@ -19,3 +19,4 @@ COPY --from=builder /app/pgcat.toml /etc/pgcat/pgcat.toml
 WORKDIR /etc/pgcat
 ENV RUST_LOG=info
 CMD ["pgcat"]
+STOPSIGNAL SIGINT

Dockerfile.ci

@@ -1,4 +1,4 @@
-FROM cimg/rust:1.67.1
+FROM cimg/rust:1.79.0
 COPY --from=sclevine/yj /bin/yj /bin/yj
 RUN /bin/yj -h
 RUN sudo apt-get update && \

charts/pgcat/Chart.yaml

@@ -4,5 +4,5 @@ description: A Helm chart for PgCat a PostgreSQL pooler and proxy (like PgBounce
 maintainers:
   - name: Wildcard
     email: support@w6d.io
-appVersion: "1.1.1"
-version: 0.1.0
+appVersion: "1.2.0"
+version: 0.2.0

charts/pgcat/values.yaml

@@ -170,13 +170,13 @@ configuration:
     connect_timeout: 5000
 
     # How long an idle connection with a server is left open (ms).
-    idle_timeout: 30000 # milliseconds
+    idle_timeout: 30000  # milliseconds
 
     # Max connection lifetime before it's closed, even if actively used.
-    server_lifetime: 86400000 # 24 hours
+    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
+    idle_client_in_transaction_timeout: 0  # milliseconds
 
     # @param configuration.general.healthcheck_timeout How much time to give `SELECT 1` health check query to return with a result (ms).
     healthcheck_timeout: 1000
@@ -240,7 +240,15 @@ configuration:
   ## the pool_name is what clients use as database name when connecting
   ## For the example below a client can connect using "postgres://sharding_user:sharding_user@pgcat_host:pgcat_port/sharded"
   ## @param [object]
-  pools: []
+  pools:
+    [{
+      name: "simple", pool_mode: "transaction",
+      users: [{username: "user", password: "pass", pool_size: 5, statement_timeout: 0}],
+      shards: [{
+        servers: [{host: "postgres", port: 5432, role: "primary"}],
+        database: "postgres"
+      }]
+    }]
     # - ## default values
     #   ##
     #   ##

dev/Dockerfile

@@ -1,4 +1,4 @@
-FROM rust:1.70-bullseye
+FROM rust:bullseye
 
 # Dependencies
 COPY --from=sclevine/yj /bin/yj /bin/yj

pgcat.service

@@ -11,6 +11,7 @@ RestartSec=1
 Environment=RUST_LOG=info
 LimitNOFILE=65536
 ExecStart=/usr/bin/pgcat /etc/pgcat.toml
+ExecReload=/bin/kill -SIGHUP $MAINPID
 
 [Install]
 WantedBy=multi-user.target

src/admin.rs

@@ -55,7 +55,12 @@ where
 
     let query_parts: Vec<&str> = query.trim_end_matches(';').split_whitespace().collect();
 
-    match query_parts[0].to_ascii_uppercase().as_str() {
+    match query_parts
+        .first()
+        .unwrap_or(&"")
+        .to_ascii_uppercase()
+        .as_str()
+    {
         "BAN" => {
             trace!("BAN");
             ban(stream, query_parts).await
@@ -84,7 +89,12 @@ where
             trace!("SHUTDOWN");
             shutdown(stream).await
         }
-        "SHOW" => match query_parts[1].to_ascii_uppercase().as_str() {
+        "SHOW" => match query_parts
+            .get(1)
+            .unwrap_or(&"")
+            .to_ascii_uppercase()
+            .as_str()
+        {
             "HELP" => {
                 trace!("SHOW HELP");
                 show_help(stream).await

src/config.rs

@@ -38,12 +38,12 @@ pub enum Role {
     Mirror,
 }
 
-impl ToString for Role {
-    fn to_string(&self) -> String {
-        match *self {
-            Role::Primary => "primary".to_string(),
-            Role::Replica => "replica".to_string(),
-            Role::Mirror => "mirror".to_string(),
+impl std::fmt::Display for Role {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Role::Primary => write!(f, "primary"),
+            Role::Replica => write!(f, "replica"),
+            Role::Mirror => write!(f, "mirror"),
         }
     }
 }
@@ -476,11 +476,11 @@ pub enum PoolMode {
     Session,
 }
 
-impl ToString for PoolMode {
-    fn to_string(&self) -> String {
-        match *self {
-            PoolMode::Transaction => "transaction".to_string(),
-            PoolMode::Session => "session".to_string(),
+impl std::fmt::Display for PoolMode {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            PoolMode::Transaction => write!(f, "transaction"),
+            PoolMode::Session => write!(f, "session"),
         }
     }
 }
@@ -493,12 +493,13 @@ pub enum LoadBalancingMode {
     #[serde(alias = "loc", alias = "LOC", alias = "least_outstanding_connections")]
     LeastOutstandingConnections,
 }
-impl ToString for LoadBalancingMode {
-    fn to_string(&self) -> String {
-        match *self {
-            LoadBalancingMode::Random => "random".to_string(),
+
+impl std::fmt::Display for LoadBalancingMode {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            LoadBalancingMode::Random => write!(f, "random"),
             LoadBalancingMode::LeastOutstandingConnections => {
-                "least_outstanding_connections".to_string()
+                write!(f, "least_outstanding_connections")
             }
         }
     }
@@ -999,15 +1000,17 @@ impl Config {
     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();
+                pool.auth_query.clone_from(&self.general.auth_query);
             }
 
             if pool.auth_query_user.is_none() {
-                pool.auth_query_user = self.general.auth_query_user.clone();
+                pool.auth_query_user
+                    .clone_from(&self.general.auth_query_user);
             }
 
             if pool.auth_query_password.is_none() {
-                pool.auth_query_password = self.general.auth_query_password.clone();
+                pool.auth_query_password
+                    .clone_from(&self.general.auth_query_password);
             }
         }
     }
@@ -1155,7 +1158,7 @@ impl Config {
             "Default max server lifetime: {}ms",
             self.general.server_lifetime
         );
-        info!("Sever round robin: {}", self.general.server_round_robin);
+        info!("Server round robin: {}", self.general.server_round_robin);
         match self.general.tls_certificate.clone() {
             Some(tls_certificate) => {
                 info!("TLS certificate: {}", tls_certificate);

src/messages.rs

@@ -733,6 +733,10 @@ pub fn configure_socket(stream: &TcpStream) {
         }
         Err(err) => error!("Could not configure socket: {}", err),
     }
+    match sock_ref.set_nodelay(true) {
+        Ok(_) => (),
+        Err(err) => error!("Could not configure TCP_NODELAY for socket: {}", err),
+    }
 }
 
 pub trait BytesMutReader {

src/pool.rs

@@ -813,7 +813,7 @@ impl ConnectionPool {
             }
         }
 
-        client_stats.checkout_success();
+        client_stats.checkout_error();
 
         Err(Error::AllServersDown)
     }

src/prometheus.rs

@@ -1,5 +1,11 @@
-use hyper::service::{make_service_fn, service_fn};
-use hyper::{Body, Method, Request, Response, Server, StatusCode};
+use http_body_util::Full;
+use hyper::body;
+use hyper::body::Bytes;
+
+use hyper::server::conn::http1;
+use hyper::service::service_fn;
+use hyper::{Method, Request, Response, StatusCode};
+use hyper_util::rt::TokioIo;
 use log::{debug, error, info};
 use phf::phf_map;
 use std::collections::HashMap;
@@ -7,6 +13,7 @@ use std::fmt;
 use std::net::SocketAddr;
 use std::sync::atomic::Ordering;
 use std::sync::Arc;
+use tokio::net::TcpListener;
 
 use crate::config::Address;
 use crate::pool::{get_all_pools, PoolIdentifier};
@@ -243,7 +250,9 @@ impl<Value: fmt::Display> PrometheusMetric<Value> {
     }
 }
 
-async fn prometheus_stats(request: Request<Body>) -> Result<Response<Body>, hyper::http::Error> {
+async fn prometheus_stats(
+    request: Request<body::Incoming>,
+) -> Result<Response<Full<Bytes>>, hyper::http::Error> {
     match (request.method(), request.uri().path()) {
         (&Method::GET, "/metrics") => {
             let mut lines = Vec::new();
@@ -374,14 +383,35 @@ fn push_server_stats(lines: &mut Vec<String>) {
 }
 
 pub async fn start_metric_server(http_addr: SocketAddr) {
-    let http_service_factory =
-        make_service_fn(|_conn| async { Ok::<_, hyper::Error>(service_fn(prometheus_stats)) });
-    let server = Server::bind(&http_addr).serve(http_service_factory);
+    let listener = TcpListener::bind(http_addr);
+    let listener = match listener.await {
+        Ok(listener) => listener,
+        Err(e) => {
+            error!("Failed to bind prometheus server to HTTP address: {}.", e);
+            return;
+        }
+    };
     info!(
         "Exposing prometheus metrics on http://{}/metrics.",
         http_addr
     );
-    if let Err(e) = server.await {
-        error!("Failed to run HTTP server: {}.", e);
+    loop {
+        let stream = match listener.accept().await {
+            Ok((stream, _)) => stream,
+            Err(e) => {
+                error!("Error accepting connection: {}", e);
+                continue;
+            }
+        };
+        let io = TokioIo::new(stream);
+
+        tokio::task::spawn(async move {
+            if let Err(err) = http1::Builder::new()
+                .serve_connection(io, service_fn(prometheus_stats))
+                .await
+            {
+                eprintln!("Error serving HTTP connection for metrics: {:?}", err);
+            }
+        });
     }
 }

src/query_router.rs

@@ -427,8 +427,12 @@ impl QueryRouter {
                         None => (),
                     };
 
-                    // If we already visited a write statement, we should be going to the primary.
-                    if !visited_write_statement {
+                    let has_locks = !query.locks.is_empty();
+
+                    if has_locks {
+                        self.active_role = Some(Role::Primary);
+                    } else if !visited_write_statement {
+                        // If we already visited a write statement, we should be going to the primary.
                         self.active_role = match self.primary_reads_enabled() {
                             false => Some(Role::Replica), // If primary should not be receiving reads, use a replica.
                             true => None,                 // Any server role is fine in this case.
@@ -499,6 +503,7 @@ impl QueryRouter {
                 table: _,
                 on: _,
                 returning: _,
+                ignore: _,
             } => {
                 // Not supported in postgres.
                 assert!(or.is_none());
@@ -506,7 +511,9 @@ impl QueryRouter {
                 assert!(after_columns.is_empty());
 
                 Self::process_table(table_name, &mut table_names);
-                Self::process_query(source, &mut exprs, &mut table_names, &Some(columns));
+                if let Some(source) = source {
+                    Self::process_query(source, &mut exprs, &mut table_names, &Some(columns));
+                }
             }
             Delete {
                 tables,
@@ -514,6 +521,8 @@ impl QueryRouter {
                 using,
                 selection,
                 returning: _,
+                order_by: _,
+                limit: _,
             } => {
                 if let Some(expr) = selection {
                     exprs.push(expr.clone());
@@ -1153,6 +1162,29 @@ mod test {
         }
     }
 
+    #[test]
+    fn test_select_for_update() {
+        QueryRouter::setup();
+        let mut qr = QueryRouter::new();
+        qr.pool_settings.query_parser_read_write_splitting = true;
+
+        let queries_in_primary_role = vec![
+            simple_query("BEGIN"), // Transaction start
+            simple_query("SELECT * FROM items WHERE id = 5 FOR UPDATE"),
+            simple_query("UPDATE items SET name = 'pumpkin' WHERE id = 5"),
+        ];
+
+        for query in queries_in_primary_role {
+            assert!(qr.infer(&qr.parse(&query).unwrap()).is_ok());
+            assert_eq!(qr.role(), Some(Role::Primary));
+        }
+
+        // query without lock do not change role
+        let query = simple_query("SELECT * FROM items WHERE id = 5");
+        assert!(qr.infer(&qr.parse(&query).unwrap()).is_ok());
+        assert_eq!(qr.role(), None);
+    }
+
     #[test]
     fn test_infer_primary_reads_enabled() {
         QueryRouter::setup();

src/sharding.rs

@@ -14,11 +14,11 @@ pub enum ShardingFunction {
     Sha1,
 }
 
-impl ToString for ShardingFunction {
-    fn to_string(&self) -> String {
-        match *self {
-            ShardingFunction::PgBigintHash => "pg_bigint_hash".to_string(),
-            ShardingFunction::Sha1 => "sha1".to_string(),
+impl std::fmt::Display for ShardingFunction {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ShardingFunction::PgBigintHash => write!(f, "pg_bigint_hash"),
+            ShardingFunction::Sha1 => write!(f, "sha1"),
         }
     }
 }

tests/ruby/admin_spec.rb

@@ -91,6 +91,27 @@ describe "Admin" do
     end
   end
 
+  [
+    "SHOW ME THE MONEY", 
+    "SHOW ME THE WAY", 
+    "SHOW UP", 
+    "SHOWTIME",
+    "HAMMER TIME",
+    "SHOWN TO BE TRUE",
+    "SHOW ",
+    "SHOW     ",
+    "SHOW 1",
+    ";;;;;"
+  ].each do |cmd|
+    describe "Bad command #{cmd}" do
+      it "does not panic and responds with PG::SystemError" do
+        admin_conn = PG::connect(processes.pgcat.admin_connection_string)
+        expect { admin_conn.async_exec(cmd) }.to raise_error(PG::SystemError).with_message(/Unsupported/)
+        admin_conn.close
+      end
+    end
+  end
+
   describe "PAUSE" do
     it "pauses all pools" do
       admin_conn = PG::connect(processes.pgcat.admin_connection_string)