mirror of
https://github.com/postgresml/pgcat.git
synced 2026-03-23 17:36:28 +00:00
1820 lines
66 KiB
Rust
1820 lines
66 KiB
Rust
use crate::errors::{ClientIdentifier, Error};
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use crate::pool::BanReason;
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/// Handle clients by pretending to be a PostgreSQL server.
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use bytes::{Buf, BufMut, BytesMut};
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use log::{debug, error, info, trace, warn};
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use once_cell::sync::Lazy;
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use std::collections::HashMap;
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use std::sync::{atomic::AtomicUsize, Arc};
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use std::time::Instant;
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use tokio::io::{split, AsyncReadExt, BufReader, ReadHalf, WriteHalf};
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use tokio::net::TcpStream;
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use tokio::sync::broadcast::Receiver;
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use tokio::sync::mpsc::Sender;
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use crate::admin::{generate_server_parameters_for_admin, handle_admin};
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use crate::auth_passthrough::refetch_auth_hash;
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use crate::config::{
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get_config, get_idle_client_in_transaction_timeout, get_prepared_statements, Address, PoolMode,
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};
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use crate::constants::*;
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use crate::messages::*;
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use crate::plugins::PluginOutput;
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use crate::pool::{get_pool, ClientServerMap, ConnectionPool};
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use crate::query_router::{Command, QueryRouter};
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use crate::server::{Server, ServerParameters};
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use crate::stats::{ClientStats, ServerStats};
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use crate::tls::Tls;
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use tokio_rustls::server::TlsStream;
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/// Incrementally count prepared statements
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/// to avoid random conflicts in places where the random number generator is weak.
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pub static PREPARED_STATEMENT_COUNTER: Lazy<Arc<AtomicUsize>> =
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Lazy::new(|| Arc::new(AtomicUsize::new(0)));
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/// Type of connection received from client.
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enum ClientConnectionType {
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Startup,
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Tls,
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CancelQuery,
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}
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/// The client state. One of these is created per client.
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pub struct Client<S, T> {
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/// The reads are buffered (8K by default).
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read: BufReader<S>,
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/// We buffer the writes ourselves because we know the protocol
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/// better than a stock buffer.
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write: T,
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/// Internal buffer, where we place messages until we have to flush
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/// them to the backend.
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buffer: BytesMut,
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/// Address
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addr: std::net::SocketAddr,
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/// The client was started with the sole reason to cancel another running query.
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cancel_mode: bool,
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/// In transaction mode, the connection is released after each transaction.
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/// Session mode has slightly higher throughput per client, but lower capacity.
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transaction_mode: bool,
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/// For query cancellation, the client is given a random process ID and secret on startup.
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process_id: i32,
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secret_key: i32,
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/// Clients are mapped to servers while they use them. This allows a client
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/// to connect and cancel a query.
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client_server_map: ClientServerMap,
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/// Client parameters, e.g. user, client_encoding, etc.
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#[allow(dead_code)]
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parameters: HashMap<String, String>,
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/// Statistics related to this client
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stats: Arc<ClientStats>,
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/// Clients want to talk to admin database.
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admin: bool,
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/// Last address the client talked to.
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last_address_id: Option<usize>,
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/// Last server process stats we talked to.
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last_server_stats: Option<Arc<ServerStats>>,
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/// Connected to server
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connected_to_server: bool,
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/// Name of the server pool for this client (This comes from the database name in the connection string)
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pool_name: String,
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/// Postgres user for this client (This comes from the user in the connection string)
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username: String,
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/// Server startup and session parameters that we're going to track
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server_parameters: ServerParameters,
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/// Used to notify clients about an impending shutdown
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shutdown: Receiver<()>,
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/// Prepared statements
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prepared_statements: HashMap<String, Parse>,
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}
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/// Client entrypoint.
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pub async fn client_entrypoint(
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mut stream: TcpStream,
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client_server_map: ClientServerMap,
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shutdown: Receiver<()>,
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drain: Sender<i32>,
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admin_only: bool,
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tls_certificate: Option<String>,
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log_client_connections: bool,
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) -> Result<(), Error> {
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// Figure out if the client wants TLS or not.
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let addr = match stream.peer_addr() {
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Ok(addr) => addr,
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Err(err) => {
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return Err(Error::SocketError(format!(
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"Failed to get peer address: {:?}",
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err
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)));
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}
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};
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match get_startup::<TcpStream>(&mut stream).await {
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// Client requested a TLS connection.
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Ok((ClientConnectionType::Tls, _)) => {
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// TLS settings are configured, will setup TLS now.
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if tls_certificate != None {
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debug!("Accepting TLS request");
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let mut yes = BytesMut::new();
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yes.put_u8(b'S');
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write_all(&mut stream, yes).await?;
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// Negotiate TLS.
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match startup_tls(stream, client_server_map, shutdown, admin_only).await {
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Ok(mut client) => {
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if log_client_connections {
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info!("Client {:?} connected (TLS)", addr);
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} else {
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debug!("Client {:?} connected (TLS)", addr);
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}
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if !client.is_admin() {
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let _ = drain.send(1).await;
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}
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let result = client.handle().await;
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if !client.is_admin() {
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let _ = drain.send(-1).await;
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}
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if result.is_err() {
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client.stats.disconnect();
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}
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result
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}
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Err(err) => Err(err),
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}
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}
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// TLS is not configured, we cannot offer it.
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else {
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// Rejecting client request for TLS.
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let mut no = BytesMut::new();
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no.put_u8(b'N');
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write_all(&mut stream, no).await?;
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// Attempting regular startup. Client can disconnect now
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// if they choose.
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match get_startup::<TcpStream>(&mut stream).await {
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// Client accepted unencrypted connection.
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Ok((ClientConnectionType::Startup, bytes)) => {
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let (read, write) = split(stream);
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// Continue with regular startup.
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match Client::startup(
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read,
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write,
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addr,
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bytes,
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client_server_map,
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shutdown,
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admin_only,
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)
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.await
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{
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Ok(mut client) => {
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if log_client_connections {
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info!("Client {:?} connected (plain)", addr);
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} else {
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debug!("Client {:?} connected (plain)", addr);
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}
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if !client.is_admin() {
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let _ = drain.send(1).await;
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}
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let result = client.handle().await;
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if !client.is_admin() {
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let _ = drain.send(-1).await;
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}
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if result.is_err() {
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client.stats.disconnect();
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}
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result
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}
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Err(err) => Err(err),
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}
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}
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// Client probably disconnected rejecting our plain text connection.
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Ok((ClientConnectionType::Tls, _))
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| Ok((ClientConnectionType::CancelQuery, _)) => Err(Error::ProtocolSyncError(
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"Bad postgres client (plain)".into(),
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)),
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Err(err) => Err(err),
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}
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}
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}
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// Client wants to use plain connection without encryption.
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Ok((ClientConnectionType::Startup, bytes)) => {
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let (read, write) = split(stream);
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// Continue with regular startup.
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match Client::startup(
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read,
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write,
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addr,
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bytes,
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client_server_map,
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shutdown,
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admin_only,
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)
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.await
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{
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Ok(mut client) => {
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if log_client_connections {
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info!("Client {:?} connected (plain)", addr);
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} else {
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debug!("Client {:?} connected (plain)", addr);
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}
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if !client.is_admin() {
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let _ = drain.send(1).await;
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}
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let result = client.handle().await;
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if !client.is_admin() {
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let _ = drain.send(-1).await;
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}
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if result.is_err() {
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client.stats.disconnect();
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}
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result
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}
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Err(err) => Err(err),
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}
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}
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// Client wants to cancel a query.
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Ok((ClientConnectionType::CancelQuery, bytes)) => {
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let (read, write) = split(stream);
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// Continue with cancel query request.
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match Client::cancel(read, write, addr, bytes, client_server_map, shutdown).await {
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Ok(mut client) => {
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info!("Client {:?} issued a cancel query request", addr);
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if !client.is_admin() {
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let _ = drain.send(1).await;
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}
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let result = client.handle().await;
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if !client.is_admin() {
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let _ = drain.send(-1).await;
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}
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if result.is_err() {
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client.stats.disconnect();
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}
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result
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}
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Err(err) => Err(err),
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}
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}
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// Something failed, probably the socket.
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Err(err) => Err(err),
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}
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}
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/// Handle the first message the client sends.
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async fn get_startup<S>(stream: &mut S) -> Result<(ClientConnectionType, BytesMut), Error>
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where
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S: tokio::io::AsyncRead + std::marker::Unpin + tokio::io::AsyncWrite,
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{
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// Get startup message length.
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let len = match stream.read_i32().await {
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Ok(len) => len,
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Err(_) => return Err(Error::ClientBadStartup),
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};
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// Get the rest of the message.
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let mut startup = vec![0u8; len as usize - 4];
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match stream.read_exact(&mut startup).await {
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Ok(_) => (),
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Err(_) => return Err(Error::ClientBadStartup),
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};
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let mut bytes = BytesMut::from(&startup[..]);
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let code = bytes.get_i32();
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match code {
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// Client is requesting SSL (TLS).
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SSL_REQUEST_CODE => Ok((ClientConnectionType::Tls, bytes)),
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// Client wants to use plain text, requesting regular startup.
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PROTOCOL_VERSION_NUMBER => Ok((ClientConnectionType::Startup, bytes)),
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// Client is requesting to cancel a running query (plain text connection).
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CANCEL_REQUEST_CODE => Ok((ClientConnectionType::CancelQuery, bytes)),
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// Something else, probably something is wrong and it's not our fault,
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// e.g. badly implemented Postgres client.
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_ => Err(Error::ProtocolSyncError(format!(
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"Unexpected startup code: {}",
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code
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))),
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}
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}
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/// Handle TLS connection negotiation.
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pub async fn startup_tls(
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stream: TcpStream,
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client_server_map: ClientServerMap,
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shutdown: Receiver<()>,
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admin_only: bool,
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) -> Result<Client<ReadHalf<TlsStream<TcpStream>>, WriteHalf<TlsStream<TcpStream>>>, Error> {
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// Negotiate TLS.
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let tls = Tls::new()?;
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let addr = match stream.peer_addr() {
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Ok(addr) => addr,
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Err(err) => {
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return Err(Error::SocketError(format!(
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"Failed to get peer address: {:?}",
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err
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)));
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}
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};
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let mut stream = match tls.acceptor.accept(stream).await {
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Ok(stream) => stream,
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// TLS negotiation failed.
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Err(err) => {
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error!("TLS negotiation failed: {:?}", err);
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return Err(Error::TlsError);
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}
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};
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// TLS negotiation successful.
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// Continue with regular startup using encrypted connection.
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match get_startup::<TlsStream<TcpStream>>(&mut stream).await {
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// Got good startup message, proceeding like normal except we
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// are encrypted now.
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Ok((ClientConnectionType::Startup, bytes)) => {
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let (read, write) = split(stream);
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Client::startup(
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read,
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write,
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addr,
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bytes,
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client_server_map,
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shutdown,
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admin_only,
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)
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.await
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}
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// Bad Postgres client.
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Ok((ClientConnectionType::Tls, _)) | Ok((ClientConnectionType::CancelQuery, _)) => {
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Err(Error::ProtocolSyncError("Bad postgres client (tls)".into()))
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}
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Err(err) => Err(err),
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}
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}
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impl<S, T> Client<S, T>
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where
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S: tokio::io::AsyncRead + std::marker::Unpin,
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T: tokio::io::AsyncWrite + std::marker::Unpin,
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{
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pub fn is_admin(&self) -> bool {
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self.admin
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}
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/// Handle Postgres client startup after TLS negotiation is complete
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/// or over plain text.
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pub async fn startup(
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mut read: S,
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mut write: T,
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addr: std::net::SocketAddr,
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bytes: BytesMut, // The rest of the startup message.
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client_server_map: ClientServerMap,
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shutdown: Receiver<()>,
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admin_only: bool,
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) -> Result<Client<S, T>, Error> {
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let parameters = parse_startup(bytes.clone())?;
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// This parameter is mandatory by the protocol.
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let username = match parameters.get("user") {
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Some(user) => user,
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None => {
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return Err(Error::ClientError(
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"Missing user parameter on client startup".into(),
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))
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}
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};
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let pool_name = match parameters.get("database") {
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Some(db) => db,
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None => username,
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};
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let application_name = match parameters.get("application_name") {
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Some(application_name) => application_name,
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None => "pgcat",
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};
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let client_identifier = ClientIdentifier::new(&application_name, &username, &pool_name);
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let admin = ["pgcat", "pgbouncer"]
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.iter()
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.filter(|db| *db == pool_name)
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.count()
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== 1;
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// Kick any client that's not admin while we're in admin-only mode.
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if !admin && admin_only {
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debug!(
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"Rejecting non-admin connection to {} when in admin only mode",
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pool_name
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);
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error_response_terminal(
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&mut write,
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"terminating connection due to administrator command",
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)
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.await?;
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return Err(Error::ShuttingDown);
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}
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|
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// Generate random backend ID and secret key
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let process_id: i32 = rand::random();
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let secret_key: i32 = rand::random();
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|
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// Perform MD5 authentication.
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// TODO: Add SASL support.
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let salt = md5_challenge(&mut write).await?;
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let code = match read.read_u8().await {
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Ok(p) => p,
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Err(_) => {
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return Err(Error::ClientSocketError(
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"password code".into(),
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client_identifier,
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))
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}
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};
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|
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// PasswordMessage
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if code as char != 'p' {
|
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return Err(Error::ProtocolSyncError(format!(
|
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"Expected p, got {}",
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code as char
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)));
|
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}
|
|
|
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let len = match read.read_i32().await {
|
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Ok(len) => len,
|
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Err(_) => {
|
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return Err(Error::ClientSocketError(
|
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"password message length".into(),
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client_identifier,
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))
|
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}
|
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};
|
|
|
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let mut password_response = vec![0u8; (len - 4) as usize];
|
|
|
|
match read.read_exact(&mut password_response).await {
|
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Ok(_) => (),
|
|
Err(_) => {
|
|
return Err(Error::ClientSocketError(
|
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"password message".into(),
|
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client_identifier,
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))
|
|
}
|
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};
|
|
|
|
// Authenticate admin user.
|
|
let (transaction_mode, mut server_parameters) = if admin {
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|
let config = get_config();
|
|
|
|
// Compare server and client hashes.
|
|
let password_hash = md5_hash_password(
|
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&config.general.admin_username,
|
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&config.general.admin_password,
|
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&salt,
|
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);
|
|
|
|
if password_hash != password_response {
|
|
let error = Error::ClientGeneralError("Invalid password".into(), client_identifier);
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|
|
warn!("{}", error);
|
|
wrong_password(&mut write, username).await?;
|
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|
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return Err(error);
|
|
}
|
|
|
|
(false, generate_server_parameters_for_admin())
|
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}
|
|
// Authenticate normal user.
|
|
else {
|
|
let mut pool = match get_pool(pool_name, username) {
|
|
Some(pool) => pool,
|
|
None => {
|
|
error_response(
|
|
&mut write,
|
|
&format!(
|
|
"No pool configured for database: {:?}, user: {:?}",
|
|
pool_name, username
|
|
),
|
|
)
|
|
.await?;
|
|
|
|
return Err(Error::ClientGeneralError(
|
|
"Invalid pool name".into(),
|
|
client_identifier,
|
|
));
|
|
}
|
|
};
|
|
|
|
// 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()));
|
|
}
|
|
|
|
let mut hash = (*pool.auth_hash.read()).clone();
|
|
|
|
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;
|
|
|
|
// If the pool hasn't been validated yet,
|
|
// connect to the servers and figure out what's what.
|
|
if !pool.validated() {
|
|
match pool.validate().await {
|
|
Ok(_) => (),
|
|
Err(err) => {
|
|
error_response(
|
|
&mut write,
|
|
&format!(
|
|
"Pool down for database: {:?}, user: {:?}",
|
|
pool_name, username
|
|
),
|
|
)
|
|
.await?;
|
|
return Err(Error::ClientError(format!("Pool down: {:?}", err)));
|
|
}
|
|
}
|
|
}
|
|
|
|
(transaction_mode, pool.server_parameters())
|
|
};
|
|
|
|
// Update the parameters to merge what the application sent and what's originally on the server
|
|
server_parameters.set_from_hashmap(¶meters, false);
|
|
|
|
debug!("Password authentication successful");
|
|
|
|
auth_ok(&mut write).await?;
|
|
write_all(&mut write, (&server_parameters).into()).await?;
|
|
backend_key_data(&mut write, process_id, secret_key).await?;
|
|
ready_for_query(&mut write).await?;
|
|
|
|
trace!("Startup OK");
|
|
let stats = Arc::new(ClientStats::new(
|
|
process_id,
|
|
application_name,
|
|
username,
|
|
pool_name,
|
|
tokio::time::Instant::now(),
|
|
));
|
|
|
|
Ok(Client {
|
|
read: BufReader::new(read),
|
|
write,
|
|
addr,
|
|
buffer: BytesMut::with_capacity(8196),
|
|
cancel_mode: false,
|
|
transaction_mode,
|
|
process_id,
|
|
secret_key,
|
|
client_server_map,
|
|
parameters: parameters.clone(),
|
|
stats,
|
|
admin,
|
|
last_address_id: None,
|
|
last_server_stats: None,
|
|
pool_name: pool_name.clone(),
|
|
username: username.clone(),
|
|
server_parameters,
|
|
shutdown,
|
|
connected_to_server: false,
|
|
prepared_statements: HashMap::new(),
|
|
})
|
|
}
|
|
|
|
/// Handle cancel request.
|
|
pub async fn cancel(
|
|
read: S,
|
|
write: T,
|
|
addr: std::net::SocketAddr,
|
|
mut bytes: BytesMut, // The rest of the startup message.
|
|
client_server_map: ClientServerMap,
|
|
shutdown: Receiver<()>,
|
|
) -> Result<Client<S, T>, Error> {
|
|
let process_id = bytes.get_i32();
|
|
let secret_key = bytes.get_i32();
|
|
Ok(Client {
|
|
read: BufReader::new(read),
|
|
write,
|
|
addr,
|
|
buffer: BytesMut::with_capacity(8196),
|
|
cancel_mode: true,
|
|
transaction_mode: false,
|
|
process_id,
|
|
secret_key,
|
|
client_server_map,
|
|
parameters: HashMap::new(),
|
|
stats: Arc::new(ClientStats::default()),
|
|
admin: false,
|
|
last_address_id: None,
|
|
last_server_stats: None,
|
|
pool_name: String::from("undefined"),
|
|
username: String::from("undefined"),
|
|
server_parameters: ServerParameters::new(),
|
|
shutdown,
|
|
connected_to_server: false,
|
|
prepared_statements: HashMap::new(),
|
|
})
|
|
}
|
|
|
|
/// Handle a connected and authenticated client.
|
|
pub async fn handle(&mut self) -> Result<(), Error> {
|
|
// The client wants to cancel a query it has issued previously.
|
|
if self.cancel_mode {
|
|
trace!("Sending CancelRequest");
|
|
|
|
let (process_id, secret_key, address, port) = {
|
|
let guard = self.client_server_map.lock();
|
|
|
|
match guard.get(&(self.process_id, self.secret_key)) {
|
|
// Drop the mutex as soon as possible.
|
|
// We found the server the client is using for its query
|
|
// that it wants to cancel.
|
|
Some((process_id, secret_key, address, port)) => {
|
|
(*process_id, *secret_key, address.clone(), *port)
|
|
}
|
|
|
|
// The client doesn't know / got the wrong server,
|
|
// we're closing the connection for security reasons.
|
|
None => return Ok(()),
|
|
}
|
|
};
|
|
|
|
// Opens a new separate connection to the server, sends the backend_id
|
|
// and secret_key and then closes it for security reasons. No other interactions
|
|
// take place.
|
|
return Server::cancel(&address, port, process_id, secret_key).await;
|
|
}
|
|
|
|
// 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.register(self.stats.clone());
|
|
|
|
// Result returned by one of the plugins.
|
|
let mut plugin_output = None;
|
|
|
|
// Prepared statement being executed
|
|
let mut prepared_statement = None;
|
|
let mut will_prepare = false;
|
|
|
|
let client_identifier = ClientIdentifier::new(
|
|
&self.server_parameters.get_application_name(),
|
|
&self.username,
|
|
&self.pool_name,
|
|
);
|
|
|
|
// Our custom protocol loop.
|
|
// We expect the client to either start a transaction with regular queries
|
|
// or issue commands for our sharding and server selection protocol.
|
|
loop {
|
|
trace!(
|
|
"Client idle, waiting for message, transaction mode: {}",
|
|
self.transaction_mode
|
|
);
|
|
|
|
// Should we rewrite prepared statements and bind messages?
|
|
let mut prepared_statements_enabled = get_prepared_statements();
|
|
|
|
// Read a complete message from the client, which normally would be
|
|
// either a `Q` (query) or `P` (prepare, extended protocol).
|
|
// We can parse it here before grabbing a server from the pool,
|
|
// in case the client is sending some custom protocol messages, e.g.
|
|
// SET SHARDING KEY TO 'bigint';
|
|
|
|
let mut message = tokio::select! {
|
|
_ = self.shutdown.recv() => {
|
|
if !self.admin {
|
|
error_response_terminal(
|
|
&mut self.write,
|
|
"terminating connection due to administrator command"
|
|
).await?;
|
|
|
|
self.stats.disconnect();
|
|
return Ok(());
|
|
}
|
|
|
|
// Admin clients ignore shutdown.
|
|
else {
|
|
read_message(&mut self.read).await?
|
|
}
|
|
},
|
|
message_result = read_message(&mut self.read) => message_result?
|
|
};
|
|
|
|
if message[0] as char == 'X' {
|
|
debug!("Client disconnecting");
|
|
|
|
self.stats.disconnect();
|
|
|
|
return Ok(());
|
|
}
|
|
|
|
// Handle admin database queries.
|
|
if self.admin {
|
|
debug!("Handling admin command");
|
|
handle_admin(&mut self.write, message, self.client_server_map.clone()).await?;
|
|
continue;
|
|
}
|
|
|
|
// Get a pool instance referenced by the most up-to-date
|
|
// pointer. This ensures we always read the latest config
|
|
// when starting a query.
|
|
let mut pool = self.get_pool().await?;
|
|
query_router.update_pool_settings(pool.settings.clone());
|
|
|
|
let mut initial_parsed_ast = None;
|
|
|
|
match message[0] as char {
|
|
// Buffer extended protocol messages even if we do not have
|
|
// a server connection yet. Hopefully, when we get the S message
|
|
// we'll be able to allocate a connection. Also, clients do not expect
|
|
// the server to respond to these messages so even if we were not able to
|
|
// allocate a connection, we wouldn't be able to send back an error message
|
|
// to the client so we buffer them and defer the decision to error out or not
|
|
// to when we get the S message
|
|
'D' => {
|
|
if prepared_statements_enabled {
|
|
let name;
|
|
(name, message) = self.rewrite_describe(message).await?;
|
|
|
|
if let Some(name) = name {
|
|
prepared_statement = Some(name);
|
|
}
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
continue;
|
|
}
|
|
|
|
'E' => {
|
|
self.buffer.put(&message[..]);
|
|
continue;
|
|
}
|
|
|
|
'Q' => {
|
|
if query_router.query_parser_enabled() {
|
|
match query_router.parse(&message) {
|
|
Ok(ast) => {
|
|
let plugin_result = query_router.execute_plugins(&ast).await;
|
|
|
|
match plugin_result {
|
|
Ok(PluginOutput::Deny(error)) => {
|
|
error_response(&mut self.write, &error).await?;
|
|
continue;
|
|
}
|
|
|
|
Ok(PluginOutput::Intercept(result)) => {
|
|
write_all(&mut self.write, result).await?;
|
|
continue;
|
|
}
|
|
|
|
_ => (),
|
|
};
|
|
|
|
let _ = query_router.infer(&ast);
|
|
|
|
initial_parsed_ast = Some(ast);
|
|
}
|
|
Err(error) => {
|
|
warn!(
|
|
"Query parsing error: {} (client: {})",
|
|
error, client_identifier
|
|
);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
'P' => {
|
|
if prepared_statements_enabled {
|
|
(prepared_statement, message) = self.rewrite_parse(message)?;
|
|
will_prepare = true;
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
|
|
if query_router.query_parser_enabled() {
|
|
match query_router.parse(&message) {
|
|
Ok(ast) => {
|
|
if let Ok(output) = query_router.execute_plugins(&ast).await {
|
|
plugin_output = Some(output);
|
|
}
|
|
|
|
let _ = query_router.infer(&ast);
|
|
}
|
|
Err(error) => {
|
|
warn!(
|
|
"Query parsing error: {} (client: {})",
|
|
error, client_identifier
|
|
);
|
|
}
|
|
};
|
|
}
|
|
|
|
continue;
|
|
}
|
|
|
|
'B' => {
|
|
if prepared_statements_enabled {
|
|
(prepared_statement, message) = self.rewrite_bind(message).await?;
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
|
|
if query_router.query_parser_enabled() {
|
|
query_router.infer_shard_from_bind(&message);
|
|
}
|
|
|
|
continue;
|
|
}
|
|
|
|
// Close (F)
|
|
'C' => {
|
|
if prepared_statements_enabled {
|
|
let close: Close = (&message).try_into()?;
|
|
|
|
if close.is_prepared_statement() && !close.anonymous() {
|
|
self.prepared_statements.remove(&close.name);
|
|
write_all_flush(&mut self.write, &close_complete()).await?;
|
|
continue;
|
|
}
|
|
}
|
|
}
|
|
|
|
_ => (),
|
|
}
|
|
|
|
// Check on plugin results.
|
|
match plugin_output {
|
|
Some(PluginOutput::Deny(error)) => {
|
|
self.buffer.clear();
|
|
error_response(&mut self.write, &error).await?;
|
|
plugin_output = None;
|
|
continue;
|
|
}
|
|
|
|
_ => (),
|
|
};
|
|
|
|
// Check if the pool is paused and wait until it's resumed.
|
|
if pool.wait_paused().await {
|
|
// Refresh pool information, something might have changed.
|
|
pool = self.get_pool().await?;
|
|
}
|
|
|
|
query_router.update_pool_settings(pool.settings.clone());
|
|
|
|
let current_shard = query_router.shard();
|
|
|
|
// Handle all custom protocol commands, if any.
|
|
match query_router.try_execute_command(&message) {
|
|
// Normal query, not a custom command.
|
|
None => (),
|
|
|
|
// SET SHARD TO
|
|
Some((Command::SetShard, _)) => {
|
|
match query_router.shard() {
|
|
None => (),
|
|
Some(selected_shard) => {
|
|
if selected_shard >= pool.shards() {
|
|
// Bad shard number, send error message to client.
|
|
query_router.set_shard(current_shard);
|
|
|
|
error_response(
|
|
&mut self.write,
|
|
&format!(
|
|
"shard {} is not configured {}, staying on shard {:?} (shard numbers start at 0)",
|
|
selected_shard,
|
|
pool.shards(),
|
|
current_shard,
|
|
),
|
|
)
|
|
.await?;
|
|
} else {
|
|
custom_protocol_response_ok(&mut self.write, "SET SHARD").await?;
|
|
}
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// SET PRIMARY READS TO
|
|
Some((Command::SetPrimaryReads, _)) => {
|
|
custom_protocol_response_ok(&mut self.write, "SET PRIMARY READS").await?;
|
|
continue;
|
|
}
|
|
|
|
// SET SHARDING KEY TO
|
|
Some((Command::SetShardingKey, _)) => {
|
|
custom_protocol_response_ok(&mut self.write, "SET SHARDING KEY").await?;
|
|
continue;
|
|
}
|
|
|
|
// SET SERVER ROLE TO
|
|
Some((Command::SetServerRole, _)) => {
|
|
custom_protocol_response_ok(&mut self.write, "SET SERVER ROLE").await?;
|
|
continue;
|
|
}
|
|
|
|
// SHOW SERVER ROLE
|
|
Some((Command::ShowServerRole, value)) => {
|
|
show_response(&mut self.write, "server role", &value).await?;
|
|
continue;
|
|
}
|
|
|
|
// SHOW SHARD
|
|
Some((Command::ShowShard, value)) => {
|
|
show_response(&mut self.write, "shard", &value).await?;
|
|
continue;
|
|
}
|
|
|
|
// SHOW PRIMARY READS
|
|
Some((Command::ShowPrimaryReads, value)) => {
|
|
show_response(&mut self.write, "primary reads", &value).await?;
|
|
continue;
|
|
}
|
|
};
|
|
|
|
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.stats)
|
|
.await
|
|
{
|
|
Ok(conn) => {
|
|
debug!("Got connection from pool");
|
|
conn
|
|
}
|
|
Err(err) => {
|
|
// Client is attempting to get results from the server,
|
|
// 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,
|
|
format!("could not get connection from the pool - {}", err).as_str(),
|
|
)
|
|
.await?;
|
|
|
|
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;
|
|
}
|
|
};
|
|
|
|
let mut reference = connection.0;
|
|
let address = connection.1;
|
|
let server = &mut *reference;
|
|
|
|
// Server is assigned to the client in case the client wants to
|
|
// cancel a query later.
|
|
server.claim(self.process_id, self.secret_key);
|
|
self.connected_to_server = true;
|
|
|
|
// Update statistics
|
|
self.stats.active();
|
|
|
|
self.last_address_id = Some(address.id);
|
|
self.last_server_stats = Some(server.stats());
|
|
|
|
debug!(
|
|
"Client {:?} talking to server {:?}",
|
|
self.addr,
|
|
server.address()
|
|
);
|
|
|
|
server.sync_parameters(&self.server_parameters).await?;
|
|
|
|
let mut initial_message = Some(message);
|
|
|
|
let idle_client_timeout_duration = match get_idle_client_in_transaction_timeout() {
|
|
0 => tokio::time::Duration::MAX,
|
|
timeout => tokio::time::Duration::from_millis(timeout),
|
|
};
|
|
|
|
// Transaction loop. Multiple queries can be issued by the client here.
|
|
// The connection belongs to the client until the transaction is over,
|
|
// or until the client disconnects if we are in session mode.
|
|
//
|
|
// If the client is in session mode, no more custom protocol
|
|
// commands will be accepted.
|
|
loop {
|
|
// Only check if we should rewrite prepared statements
|
|
// in session mode. In transaction mode, we check at the beginning of
|
|
// each transaction.
|
|
if !self.transaction_mode {
|
|
prepared_statements_enabled = get_prepared_statements();
|
|
}
|
|
|
|
debug!("Prepared statement active: {:?}", prepared_statement);
|
|
|
|
// We are processing a prepared statement.
|
|
if let Some(ref name) = prepared_statement {
|
|
debug!("Checking prepared statement is on server");
|
|
// Get the prepared statement the server expects to see.
|
|
let statement = match self.prepared_statements.get(name) {
|
|
Some(statement) => {
|
|
debug!("Prepared statement `{}` found in cache", name);
|
|
statement
|
|
}
|
|
None => {
|
|
return Err(Error::ClientError(format!(
|
|
"prepared statement `{}` not found",
|
|
name
|
|
)))
|
|
}
|
|
};
|
|
|
|
// Since it's already in the buffer, we don't need to prepare it on this server.
|
|
if will_prepare {
|
|
server.will_prepare(&statement.name);
|
|
will_prepare = false;
|
|
} else {
|
|
// The statement is not prepared on the server, so we need to prepare it.
|
|
if server.should_prepare(&statement.name) {
|
|
match server.prepare(statement).await {
|
|
Ok(_) => (),
|
|
Err(err) => {
|
|
pool.ban(
|
|
&address,
|
|
BanReason::MessageSendFailed,
|
|
Some(&self.stats),
|
|
);
|
|
return Err(err);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Done processing the prepared statement.
|
|
prepared_statement = None;
|
|
}
|
|
|
|
let mut message = match initial_message {
|
|
None => {
|
|
trace!("Waiting for message inside transaction or in session mode");
|
|
|
|
// This is not an initial message so discard the initial_parsed_ast
|
|
initial_parsed_ast.take();
|
|
|
|
match tokio::time::timeout(
|
|
idle_client_timeout_duration,
|
|
read_message(&mut self.read),
|
|
)
|
|
.await
|
|
{
|
|
Ok(Ok(message)) => message,
|
|
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);
|
|
}
|
|
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,
|
|
self.username,
|
|
query_router.shard(),
|
|
query_router.role()
|
|
);
|
|
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
Some(message) => {
|
|
initial_message = None;
|
|
message
|
|
}
|
|
};
|
|
|
|
// The message will be forwarded to the server intact. We still would like to
|
|
// parse it below to figure out what to do with it.
|
|
|
|
// Safe to unwrap because we know this message has a certain length and has the code
|
|
// This reads the first byte without advancing the internal pointer and mutating the bytes
|
|
let code = *message.get(0).unwrap() as char;
|
|
|
|
trace!("Message: {}", code);
|
|
|
|
match code {
|
|
// Query
|
|
'Q' => {
|
|
if query_router.query_parser_enabled() {
|
|
// We don't want to parse again if we already parsed it as the initial message
|
|
let ast = match initial_parsed_ast {
|
|
Some(_) => Some(initial_parsed_ast.take().unwrap()),
|
|
None => match query_router.parse(&message) {
|
|
Ok(ast) => Some(ast),
|
|
Err(error) => {
|
|
warn!(
|
|
"Query parsing error: {} (client: {})",
|
|
error, client_identifier
|
|
);
|
|
None
|
|
}
|
|
},
|
|
};
|
|
|
|
if let Some(ast) = ast {
|
|
let plugin_result = query_router.execute_plugins(&ast).await;
|
|
|
|
match plugin_result {
|
|
Ok(PluginOutput::Deny(error)) => {
|
|
error_response(&mut self.write, &error).await?;
|
|
continue;
|
|
}
|
|
|
|
Ok(PluginOutput::Intercept(result)) => {
|
|
write_all(&mut self.write, result).await?;
|
|
continue;
|
|
}
|
|
|
|
_ => (),
|
|
};
|
|
}
|
|
}
|
|
debug!("Sending query to server");
|
|
|
|
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();
|
|
server
|
|
.stats()
|
|
.transaction(&self.server_parameters.get_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 && !server.in_copy_mode() {
|
|
self.stats.idle();
|
|
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Terminate
|
|
'X' => {
|
|
server.checkin_cleanup().await?;
|
|
self.stats.disconnect();
|
|
self.release();
|
|
|
|
if prepared_statements_enabled {
|
|
server.maintain_cache().await?;
|
|
}
|
|
|
|
return Ok(());
|
|
}
|
|
|
|
// Parse
|
|
// The query with placeholders is here, e.g. `SELECT * FROM users WHERE email = $1 AND active = $2`.
|
|
'P' => {
|
|
if prepared_statements_enabled {
|
|
(prepared_statement, message) = self.rewrite_parse(message)?;
|
|
will_prepare = true;
|
|
}
|
|
|
|
if query_router.query_parser_enabled() {
|
|
if let Ok(ast) = query_router.parse(&message) {
|
|
if let Ok(output) = query_router.execute_plugins(&ast).await {
|
|
plugin_output = Some(output);
|
|
}
|
|
}
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
}
|
|
|
|
// Bind
|
|
// The placeholder's replacements are here, e.g. 'user@email.com' and 'true'
|
|
'B' => {
|
|
if prepared_statements_enabled {
|
|
(prepared_statement, message) = self.rewrite_bind(message).await?;
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
}
|
|
|
|
// Describe
|
|
// Command a client can issue to describe a previously prepared named statement.
|
|
'D' => {
|
|
if prepared_statements_enabled {
|
|
let name;
|
|
(name, message) = self.rewrite_describe(message).await?;
|
|
|
|
if let Some(name) = name {
|
|
prepared_statement = Some(name);
|
|
}
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
}
|
|
|
|
// Close the prepared statement.
|
|
'C' => {
|
|
if prepared_statements_enabled {
|
|
let close: Close = (&message).try_into()?;
|
|
|
|
if close.is_prepared_statement() && !close.anonymous() {
|
|
match self.prepared_statements.get(&close.name) {
|
|
Some(parse) => {
|
|
server.will_close(&parse.generated_name);
|
|
}
|
|
|
|
// A prepared statement slipped through? Not impossible, since we don't support PREPARE yet.
|
|
None => (),
|
|
};
|
|
}
|
|
}
|
|
|
|
self.buffer.put(&message[..]);
|
|
}
|
|
|
|
// Execute
|
|
// Execute a prepared statement prepared in `P` and bound in `B`.
|
|
'E' => {
|
|
self.buffer.put(&message[..]);
|
|
}
|
|
|
|
// Sync
|
|
// Frontend (client) is asking for the query result now.
|
|
'S' => {
|
|
debug!("Sending query to server");
|
|
|
|
match plugin_output {
|
|
Some(PluginOutput::Deny(error)) => {
|
|
error_response(&mut self.write, &error).await?;
|
|
plugin_output = None;
|
|
self.buffer.clear();
|
|
continue;
|
|
}
|
|
|
|
Some(PluginOutput::Intercept(result)) => {
|
|
write_all(&mut self.write, result).await?;
|
|
plugin_output = None;
|
|
self.buffer.clear();
|
|
continue;
|
|
}
|
|
|
|
_ => (),
|
|
};
|
|
|
|
self.buffer.put(&message[..]);
|
|
|
|
let first_message_code = (*self.buffer.get(0).unwrap_or(&0)) as char;
|
|
|
|
// Almost certainly true
|
|
if first_message_code == 'P' && !prepared_statements_enabled {
|
|
// Message layout
|
|
// P followed by 32 int followed by null-terminated statement name
|
|
// So message code should be in offset 0 of the buffer, first character
|
|
// in prepared statement name would be index 5
|
|
let first_char_in_name = *self.buffer.get(5).unwrap_or(&0);
|
|
if first_char_in_name != 0 {
|
|
// This is a named prepared statement
|
|
// Server connection state will need to be cleared at checkin
|
|
server.mark_dirty();
|
|
}
|
|
}
|
|
|
|
self.send_and_receive_loop(
|
|
code,
|
|
None,
|
|
server,
|
|
&address,
|
|
&pool,
|
|
&self.stats.clone(),
|
|
)
|
|
.await?;
|
|
|
|
self.buffer.clear();
|
|
|
|
if !server.in_transaction() {
|
|
self.stats.transaction();
|
|
server
|
|
.stats()
|
|
.transaction(&self.server_parameters.get_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 && !server.in_copy_mode() {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// CopyData
|
|
'd' => {
|
|
self.buffer.put(&message[..]);
|
|
|
|
// Want to limit buffer size
|
|
if self.buffer.len() > 8196 {
|
|
// Forward the data to the server,
|
|
self.send_server_message(server, &self.buffer, &address, &pool)
|
|
.await?;
|
|
self.buffer.clear();
|
|
}
|
|
}
|
|
|
|
// CopyDone or CopyFail
|
|
// Copy is done, successfully or not.
|
|
'c' | 'f' => {
|
|
// We may already have some copy data in the buffer, add this message to buffer
|
|
self.buffer.put(&message[..]);
|
|
|
|
self.send_server_message(server, &self.buffer, &address, &pool)
|
|
.await?;
|
|
|
|
// Clear the buffer
|
|
self.buffer.clear();
|
|
|
|
let response = self
|
|
.receive_server_message(server, &address, &pool, &self.stats.clone())
|
|
.await?;
|
|
|
|
match write_all_flush(&mut self.write, &response).await {
|
|
Ok(_) => (),
|
|
Err(err) => {
|
|
server.mark_bad();
|
|
return Err(err);
|
|
}
|
|
};
|
|
|
|
if !server.in_transaction() {
|
|
self.stats.transaction();
|
|
server
|
|
.stats()
|
|
.transaction(self.server_parameters.get_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 {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Some unexpected message. We either did not implement the protocol correctly
|
|
// or this is not a Postgres client we're talking to.
|
|
_ => {
|
|
error!("Unexpected code: {}", code);
|
|
}
|
|
}
|
|
}
|
|
|
|
// 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?;
|
|
|
|
if prepared_statements_enabled {
|
|
server.maintain_cache().await?;
|
|
}
|
|
|
|
server.stats().idle();
|
|
self.connected_to_server = false;
|
|
|
|
self.release();
|
|
self.stats.idle();
|
|
}
|
|
}
|
|
|
|
/// Retrieve connection pool, if it exists.
|
|
/// Return an error to the client otherwise.
|
|
async fn get_pool(&mut self) -> Result<ConnectionPool, Error> {
|
|
match get_pool(&self.pool_name, &self.username) {
|
|
Some(pool) => Ok(pool),
|
|
None => {
|
|
error_response(
|
|
&mut self.write,
|
|
&format!(
|
|
"No pool configured for database: {}, user: {}",
|
|
self.pool_name, self.username
|
|
),
|
|
)
|
|
.await?;
|
|
|
|
Err(Error::ClientError(format!(
|
|
"Invalid pool name {{ username: {}, pool_name: {}, application_name: {} }}",
|
|
self.pool_name,
|
|
self.username,
|
|
self.server_parameters.get_application_name()
|
|
)))
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Rewrite Parse (F) message to set the prepared statement name to one we control.
|
|
/// Save it into the client cache.
|
|
fn rewrite_parse(&mut self, message: BytesMut) -> Result<(Option<String>, BytesMut), Error> {
|
|
let parse: Parse = (&message).try_into()?;
|
|
|
|
let name = parse.name.clone();
|
|
|
|
// Don't rewrite anonymous prepared statements
|
|
if parse.anonymous() {
|
|
debug!("Anonymous prepared statement");
|
|
return Ok((None, message));
|
|
}
|
|
|
|
let parse = parse.rename();
|
|
|
|
debug!(
|
|
"Renamed prepared statement `{}` to `{}` and saved to cache",
|
|
name, parse.name
|
|
);
|
|
|
|
self.prepared_statements.insert(name.clone(), parse.clone());
|
|
|
|
Ok((Some(name), parse.try_into()?))
|
|
}
|
|
|
|
/// Rewrite the Bind (F) message to use the prepared statement name
|
|
/// saved in the client cache.
|
|
async fn rewrite_bind(
|
|
&mut self,
|
|
message: BytesMut,
|
|
) -> Result<(Option<String>, BytesMut), Error> {
|
|
let bind: Bind = (&message).try_into()?;
|
|
let name = bind.prepared_statement.clone();
|
|
|
|
if bind.anonymous() {
|
|
debug!("Anonymous bind message");
|
|
return Ok((None, message));
|
|
}
|
|
|
|
match self.prepared_statements.get(&name) {
|
|
Some(prepared_stmt) => {
|
|
let bind = bind.reassign(prepared_stmt);
|
|
|
|
debug!("Rewrote bind `{}` to `{}`", name, bind.prepared_statement);
|
|
|
|
Ok((Some(name), bind.try_into()?))
|
|
}
|
|
None => {
|
|
debug!("Got bind for unknown prepared statement {:?}", bind);
|
|
|
|
error_response(
|
|
&mut self.write,
|
|
&format!(
|
|
"prepared statement \"{}\" does not exist",
|
|
bind.prepared_statement
|
|
),
|
|
)
|
|
.await?;
|
|
|
|
Err(Error::ClientError(format!(
|
|
"Prepared statement `{}` doesn't exist",
|
|
name
|
|
)))
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Rewrite the Describe (F) message to use the prepared statement name
|
|
/// saved in the client cache.
|
|
async fn rewrite_describe(
|
|
&mut self,
|
|
message: BytesMut,
|
|
) -> Result<(Option<String>, BytesMut), Error> {
|
|
let describe: Describe = (&message).try_into()?;
|
|
let name = describe.statement_name.clone();
|
|
|
|
if describe.anonymous() {
|
|
debug!("Anonymous describe");
|
|
return Ok((None, message));
|
|
}
|
|
|
|
match self.prepared_statements.get(&name) {
|
|
Some(prepared_stmt) => {
|
|
let describe = describe.rename(&prepared_stmt.name);
|
|
|
|
debug!(
|
|
"Rewrote describe `{}` to `{}`",
|
|
name, describe.statement_name
|
|
);
|
|
|
|
Ok((Some(name), describe.try_into()?))
|
|
}
|
|
|
|
None => {
|
|
debug!("Got describe for unknown prepared statement {:?}", describe);
|
|
|
|
Ok((None, message))
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Release the server from the client: it can't cancel its queries anymore.
|
|
pub fn release(&self) {
|
|
let mut guard = self.client_server_map.lock();
|
|
guard.remove(&(self.process_id, self.secret_key));
|
|
}
|
|
|
|
async fn send_and_receive_loop(
|
|
&mut self,
|
|
code: char,
|
|
message: Option<&BytesMut>,
|
|
server: &mut Server,
|
|
address: &Address,
|
|
pool: &ConnectionPool,
|
|
client_stats: &ClientStats,
|
|
) -> Result<(), Error> {
|
|
debug!("Sending {} to server", code);
|
|
|
|
let message = match message {
|
|
Some(message) => message,
|
|
None => &self.buffer,
|
|
};
|
|
|
|
self.send_server_message(server, message, address, pool)
|
|
.await?;
|
|
|
|
let query_start = Instant::now();
|
|
// 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, client_stats)
|
|
.await?;
|
|
|
|
match write_all_flush(&mut self.write, &response).await {
|
|
Ok(_) => (),
|
|
Err(err) => {
|
|
server.mark_bad();
|
|
return Err(err);
|
|
}
|
|
};
|
|
|
|
if !server.is_data_available() {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Report query executed statistics.
|
|
client_stats.query();
|
|
server.stats().query(
|
|
Instant::now().duration_since(query_start).as_millis() as u64,
|
|
&self.server_parameters.get_application_name(),
|
|
);
|
|
|
|
Ok(())
|
|
}
|
|
|
|
async fn send_server_message(
|
|
&self,
|
|
server: &mut Server,
|
|
message: &BytesMut,
|
|
address: &Address,
|
|
pool: &ConnectionPool,
|
|
) -> Result<(), Error> {
|
|
match server.send(message).await {
|
|
Ok(_) => Ok(()),
|
|
Err(err) => {
|
|
pool.ban(address, BanReason::MessageSendFailed, Some(&self.stats));
|
|
Err(err)
|
|
}
|
|
}
|
|
}
|
|
|
|
async fn receive_server_message(
|
|
&mut self,
|
|
server: &mut Server,
|
|
address: &Address,
|
|
pool: &ConnectionPool,
|
|
client_stats: &ClientStats,
|
|
) -> Result<BytesMut, Error> {
|
|
let statement_timeout_duration = match pool.settings.user.statement_timeout {
|
|
0 => tokio::time::Duration::MAX,
|
|
timeout => tokio::time::Duration::from_millis(timeout),
|
|
};
|
|
|
|
match tokio::time::timeout(
|
|
statement_timeout_duration,
|
|
server.recv(Some(&mut self.server_parameters)),
|
|
)
|
|
.await
|
|
{
|
|
Ok(result) => match result {
|
|
Ok(message) => Ok(message),
|
|
Err(err) => {
|
|
pool.ban(address, BanReason::MessageReceiveFailed, Some(client_stats));
|
|
error_response_terminal(
|
|
&mut self.write,
|
|
&format!("error receiving data from server: {:?}", err),
|
|
)
|
|
.await?;
|
|
Err(err)
|
|
}
|
|
},
|
|
Err(_) => {
|
|
error!(
|
|
"Statement timeout while talking to {:?} with user {}",
|
|
address, pool.settings.user.username
|
|
);
|
|
server.mark_bad();
|
|
pool.ban(address, BanReason::StatementTimeout, Some(client_stats));
|
|
error_response_terminal(&mut self.write, "pool statement timeout").await?;
|
|
Err(Error::StatementTimeout)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<S, T> Drop for Client<S, T> {
|
|
fn drop(&mut self) {
|
|
let mut guard = self.client_server_map.lock();
|
|
guard.remove(&(self.process_id, self.secret_key));
|
|
|
|
// Dirty shutdown
|
|
// TODO: refactor, this is not the best way to handle state management.
|
|
if self.connected_to_server && self.last_server_stats.is_some() {
|
|
self.last_server_stats.as_ref().unwrap().idle();
|
|
}
|
|
}
|
|
}
|