chore: reproduce idle-in-transaction extended protocol bug (#851)

- chore: upgrade bindgen in `pg_query` to work with latest clang
- chore: add test case that demonstrates partial extended exchange
preventing `idle_in_transaction_session_timeout` from firing

Author: levkk

Cargo.lock

@@ -15,7 +15,7 @@ crate-type = ["rlib", "cdylib"]
 
 [dependencies]
 libloading = "0.8"
-pg_query = { git = "https://github.com/pgdogdev/pg_query.rs.git", rev = "f8c216209f90525f065b47ffde9eb5da803d2dc6" }
+pg_query = { git = "https://github.com/pgdogdev/pg_query.rs.git", rev = "d30dcb47fdf3fa77d102b813a34392146642903a" }
 pgdog-macros = { path = "../pgdog-macros", version = "0.1.1" }
 
 tracing = "0.1"

pgdog-plugin/Cargo.toml

@@ -43,7 +43,7 @@ base64 = "0.22"
 md5 = "0.7"
 futures = "0.3"
 csv-core = "0.1"
-pg_query = { git = "https://github.com/pgdogdev/pg_query.rs.git", rev = "f8c216209f90525f065b47ffde9eb5da803d2dc6" }
+pg_query = { git = "https://github.com/pgdogdev/pg_query.rs.git", rev = "d30dcb47fdf3fa77d102b813a34392146642903a" }
 regex = "1"
 semver = "1"
 uuid = { version = "1", features = ["v4", "serde"] }

pgdog/Cargo.toml

@@ -0,0 +1,78 @@
+use std::time::Duration;
+
+use pgdog_postgres_types::Format;
+use tokio::time::sleep;
+
+use crate::{
+    backend::{server::test::test_server, Server},
+    expect_message,
+    net::{DataRow, RowDescription},
+};
+
+use super::prelude::*;
+
+#[tokio::test]
+async fn test_idle_in_transaction_partial_recovery() {
+    crate::logger();
+
+    // Direct connection for testing state.
+    let mut test_server = test_server().await;
+
+    let mut client = TestClient::new_replicas(Parameters::default())
+        .await
+        .leak_pool();
+
+    client.send_simple(Query::new("BEGIN")).await;
+    client.read_until('Z').await.unwrap();
+
+    client
+        .send_simple(Query::new("SELECT pg_backend_pid()::text"))
+        .await;
+    expect_message!(client.read().await, RowDescription);
+    let rd = expect_message!(client.read().await, DataRow);
+    let pid: String = rd.get(0, Format::Text).unwrap();
+
+    client.read_until('Z').await.unwrap();
+
+    // This won't fire because we'll be stuck inside the extended exchange.
+    client
+        .send_simple(Query::new("SET idle_in_transaction_session_timeout TO 100"))
+        .await;
+    client.read_until('Z').await.unwrap();
+
+    client.send(Parse::named("__test_1", "SELECT $1")).await;
+    client.send(Flush).await;
+    client.try_process().await.unwrap();
+    client.read_until('1').await.unwrap();
+
+    // Stuck inside extended exchange, idle in transaction timeout will not fire.
+    sleep(Duration::from_millis(100)).await;
+
+    client.send(Parse::named("__test_2", "SELECT $1")).await;
+    client.send(Flush).await;
+
+    client.try_process().await.unwrap();
+    client.read_until('1').await.unwrap();
+
+    // Server in active state.
+    assert_server_state(&mut test_server, &pid, "active").await;
+
+    client.send(Terminate).await;
+    drop(client);
+
+    sleep(Duration::from_millis(50)).await;
+
+    // Cleanup works.
+    assert_server_state(&mut test_server, &pid, "idle").await;
+}
+
+async fn assert_server_state(conn: &mut Server, pid: &str, expected: &str) {
+    let response: Vec<String> = conn
+        .fetch_all(format!(
+            "SELECT state::text FROM pg_stat_activity WHERE pid = {}",
+            pid
+        ))
+        .await
+        .unwrap();
+    assert_eq!(response[0], expected);
+}

pgdog/src/frontend/client/query_engine/test/idle_in_transaction_recovery.rs

@@ -13,6 +13,7 @@ mod extended;
 mod fatal_error;
 mod graceful_disconnect;
 mod graceful_shutdown;
+mod idle_in_transaction_recovery;
 mod lock_session;
 mod omni;
 pub mod prelude;

pgdog/src/frontend/client/query_engine/test/mod.rs

@@ -111,6 +111,7 @@ pub struct TestClient {
     pub(crate) client: Client,
     pub(crate) engine: QueryEngine,
     pub(crate) conn: TcpStream,
+    pub(crate) leak_pool: bool,
 }
 
 impl TestClient {
@@ -119,13 +120,14 @@ impl TestClient {
     ///
     /// Config needs to be loaded.
     ///
-    async fn new(params: Parameters) -> Self {
+    pub(crate) async fn new(params: Parameters) -> Self {
         let (conn, client) = new_client_pair(params).await;
 
         Self {
             conn,
             engine: QueryEngine::from_client(&client).expect("create query engine from client"),
             client,
+            leak_pool: false,
         }
     }
 
@@ -135,6 +137,11 @@ impl TestClient {
         Self::new(params).await
     }
 
+    pub(crate) fn leak_pool(mut self) -> Self {
+        self.leak_pool = true;
+        self
+    }
+
     /// New client with replicas but not sharded.
     pub(crate) async fn new_replicas(params: Parameters) -> Self {
         load_test_replicas();
@@ -243,7 +250,9 @@ impl TestClient {
 
 impl Drop for TestClient {
     fn drop(&mut self) {
-        shutdown();
+        if !self.leak_pool {
+            shutdown();
+        }
     }
 }