Restore the ability to filter spammy log messages (#530)

* Move connection checkin log messages to their own target

Under heavy load they can happen thousands of times per second, and
should generally be considered a nuisance at best. This marks the state
discard as an info rather than a warning, and moves all the messages
into their own log-target, so they can be filtered separately from the
more relevant warnings.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

* Remove left-over env_logger dependencies

When moving to tracing-subscriber for logging, the env_logger
dependencies were left around, this cuts them out as dead code.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

* Restore ability to filter log messages at runtime

This restores the RUST_LOG filters from env_logger but now with the
tracing subscriber setup. The filters are chained so commandline options
mark the default in case either option is set, which should be the path
of least confusion for users.  ( RUST_LOG setting level to debug, and
commandline to warning is an odd user case, and I don't know what a user
who does that is expecting. )

It also bumps the version number as a fix to see which versions have
which behaviour.

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

---------

Signed-off-by: D.S. Ljungmark <spider@skuggor.se>

Author: Spindel

Cargo.lock

@@ -1,6 +1,6 @@
 [package]
 name = "pgcat"
-version = "1.1.0"
+version = "1.1.1"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
@@ -22,7 +22,6 @@ once_cell = "1"
 sqlparser = {version = "0.34", features = ["visitor"] }
 log = "0.4"
 arc-swap = "1"
-env_logger = "0.10"
 parking_lot = "0.12.1"
 hmac = "0.12"
 sha2 = "0.10"
@@ -48,7 +47,7 @@ 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"]}
+tracing-subscriber = { version = "0.3.17", features = ["json", "env-filter", "std"]}
 
 [target.'cfg(not(target_env = "msvc"))'.dependencies]
 jemallocator = "0.5.0"

Cargo.toml

@@ -1,9 +1,14 @@
 use crate::cmd_args::{Args, LogFormat};
 use tracing_subscriber;
+use tracing_subscriber::EnvFilter;
 
 pub fn init(args: &Args) {
+    // Iniitalize a default filter, and then override the builtin default "warning" with our
+    // commandline, (default: "info")
+    let filter = EnvFilter::from_default_env().add_directive(args.log_level.into());
+
     let trace_sub = tracing_subscriber::fmt()
-        .with_max_level(args.log_level)
+        .with_env_filter(filter)
         .with_ansi(!args.no_color);
 
     match args.log_format {

src/logger.rs

@@ -23,7 +23,6 @@ extern crate arc_swap;
 extern crate async_trait;
 extern crate bb8;
 extern crate bytes;
-extern crate env_logger;
 extern crate exitcode;
 extern crate log;
 extern crate md5;

src/main.rs

@@ -1136,7 +1136,7 @@ impl Server {
         // server connection thrashing if clients repeatedly do this.
         // Instead, we ROLLBACK that transaction before putting the connection back in the pool
         if self.in_transaction() {
-            warn!("Server returned while still in transaction, rolling back transaction");
+            warn!(target: "pgcat::server::cleanup", "Server returned while still in transaction, rolling back transaction");
             self.query("ROLLBACK").await?;
         }
 
@@ -1146,14 +1146,14 @@ impl Server {
         // send `DISCARD ALL` if we think the session is altered instead of just sending
         // it before each checkin.
         if self.cleanup_state.needs_cleanup() && self.cleanup_connections {
-            warn!("Server returned with session state altered, discarding state ({}) for application {}", self.cleanup_state, self.application_name);
+            info!(target: "pgcat::server::cleanup", "Server returned with session state altered, discarding state ({}) for application {}", self.cleanup_state, self.application_name);
             self.query("DISCARD ALL").await?;
             self.query("RESET ROLE").await?;
             self.cleanup_state.reset();
         }
 
         if self.in_copy_mode() {
-            warn!("Server returned while still in copy-mode");
+            warn!(target: "pgcat::server::cleanup", "Server returned while still in copy-mode");
         }
 
         Ok(())