#829: read/write splitting on CTE mutable statements

.gitignore

@@ -12,4 +12,3 @@ dev/cache
 !dev/cache/.keepme
 .venv
 **/__pycache__
-.bundle

Cargo.lock

@@ -192,11 +192,12 @@ checksum = "604178f6c5c21f02dc555784810edfb88d34ac2c73b2eae109655649ee73ce3d"
 
 [[package]]
 name = "bb8"
-version = "0.8.6"
+version = "0.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d89aabfae550a5c44b43ab941844ffcd2e993cb6900b342debf59e9ea74acdb8"
+checksum = "98b4b0f25f18bcdc3ac72bdb486ed0acf7e185221fd4dc985bc15db5800b0ba2"
 dependencies = [
  "async-trait",
+ "futures-channel",
  "futures-util",
  "parking_lot",
  "tokio",
@@ -1525,9 +1526,9 @@ checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
 [[package]]
 name = "sqlparser"
-version = "0.52.0"
+version = "0.41.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9a875d8cd437cc8a97e9aeaeea352ec9a19aea99c23e9effb17757291de80b08"
+checksum = "5cc2c25a6c66789625ef164b4c7d2e548d627902280c13710d33da8222169964"
 dependencies = [
  "log",
  "sqlparser_derive",

Cargo.toml

@@ -8,7 +8,7 @@ edition = "2021"
 tokio = { version = "1", features = ["full"] }
 bytes = "1"
 md-5 = "0.10"
-bb8 = "=0.8.6"
+bb8 = "0.8.1"
 async-trait = "0.1"
 rand = "0.8"
 chrono = "0.4"
@@ -19,7 +19,7 @@ serde_derive = "1"
 regex = "1"
 num_cpus = "1"
 once_cell = "1"
-sqlparser = { version = "0.52", features = ["visitor"] }
+sqlparser = { version = "0.41", features = ["visitor"] }
 log = "0.4"
 arc-swap = "1"
 parking_lot = "0.12.1"

charts/pgcat/Chart.yaml

@@ -2,7 +2,7 @@ apiVersion: v2
 name: pgcat
 description: A Helm chart for PgCat a PostgreSQL pooler and proxy (like PgBouncer) with support for sharding, load balancing, failover and mirroring.
 maintainers:
-  - name: PostgresML
-    email: team@postgresml.org
+  - name: Wildcard
+    email: support@w6d.io
 appVersion: "1.2.0"
-version: 0.2.5
+version: 0.2.1

cr.yaml

@@ -1,2 +1 @@
 sign: false
-pages_branch: main

pgcat.toml

@@ -179,7 +179,7 @@ primary_reads_enabled = true
 # `random`: picks a shard at random
 # `random_healthy`: picks a shard at random favoring shards with the least number of recent errors
 # `shard_<number>`: e.g. shard_0, shard_4, etc. picks a specific shard, everytime
-# default_shard = "shard_0"
+# no_shard_specified_behavior = "shard_0"
 
 # So what if you wanted to implement a different hashing function,
 # or you've already built one and you want this pooler to use it?

src/client.rs

@@ -881,7 +881,6 @@ where
         };
 
         query_router.update_pool_settings(&pool.settings);
-        query_router.set_default_role();
 
         // Our custom protocol loop.
         // We expect the client to either start a transaction with regular queries

src/query_router.rs

@@ -386,14 +386,14 @@ impl QueryRouter {
         }
     }
 
-    /// Determines if a query is a mutation or not.
-    fn is_mutation_query(q: &sqlparser::ast::Query) -> bool {
+    /// Determines if a query is mutable or not.
+    fn query_is_mutable_statement(q: &sqlparser::ast::Query) -> bool {
         use sqlparser::ast::*;
 
         match q.body.as_ref() {
             SetExpr::Insert(_) => true,
             SetExpr::Update(_) => true,
-            SetExpr::Query(q) => Self::is_mutation_query(q),
+            SetExpr::Query(q) => Self::query_is_mutable_statement(q),
             _ => false,
         }
     }
@@ -440,9 +440,9 @@ impl QueryRouter {
                     };
 
                     let has_locks = !query.locks.is_empty();
-                    let has_mutation = Self::is_mutation_query(query);
+                    let is_mutable_statement = Self::query_is_mutable_statement(query);
 
-                    if has_locks || has_mutation {
+                    if has_locks || is_mutable_statement {
                         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.
@@ -1061,11 +1061,6 @@ impl QueryRouter {
         self.active_shard
     }
 
-    /// Set active_role as the default_role specified in the pool.
-    pub fn set_default_role(&mut self) {
-        self.active_role = self.pool_settings.default_role;
-    }
-
     /// Get the current desired server role we should be talking to.
     pub fn role(&self) -> Option<Role> {
         self.active_role

tests/ruby/load_balancing_spec.rb

@@ -56,41 +56,6 @@ describe "Random Load Balancing" do
       end
     end
   end
-
-  context "when all replicas are down " do
-    let(:processes) { Helpers::Pgcat.single_shard_setup("sharded_db", 5, "transaction", "random", "debug", {"default_role" => "replica"}) }
-
-    it "unbans them automatically to prevent false positives in health checks that could make all replicas unavailable" do
-      conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
-      failed_count = 0
-      number_of_replicas = processes[:replicas].length
-
-      # Take down all replicas
-      processes[:replicas].each(&:take_down)
-
-      (number_of_replicas + 1).times do |n|
-        conn.async_exec("SELECT 1 + 2")
-      rescue
-        conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
-        failed_count += 1
-      end
-
-      expect(failed_count).to eq(number_of_replicas + 1)
-      failed_count = 0
-
-      # Ban_time is configured to 60 so this reset will only work
-      # if the replicas are unbanned automatically
-      processes[:replicas].each(&:reset)
-
-      number_of_replicas.times do
-        conn.async_exec("SELECT 1 + 2")
-      rescue
-        conn = PG.connect(processes.pgcat.connection_string("sharded_db", "sharding_user"))
-        failed_count += 1
-      end
-      expect(failed_count).to eq(0)
-    end
-  end
 end
 
 describe "Least Outstanding Queries Load Balancing" do
@@ -196,3 +161,4 @@ describe "Least Outstanding Queries Load Balancing" do
     end
   end
 end
+