Fix tracing logging functions (#945)

* Add file header

* Fix log functions

* Remove erroneous code in valgrind CI

* Address comments

ci/valgrind-check/Cargo.toml

@@ -23,11 +23,11 @@ description = "Internal crate for zenoh."
 
 [dependencies]
 tokio = { version = "1.35.1",  features = ["rt-multi-thread", "time", "io-std"] }
-tracing-subscriber = {version = "0.3", features = ["json", "env-filter"]}
+tracing-subscriber = { version = "0.3", features = ["json", "env-filter"] }
 futures = "0.3.25"
 zenoh = { path = "../../zenoh/" }
 zenoh-runtime = { path = "../../commons/zenoh-runtime/" }
-zenoh-util = { path = "../../commons/zenoh-util/" }
+zenoh-util = { path = "../../commons/zenoh-util/", features = ["test"] }
 
 [[bin]]
 name = "pub_sub"

ci/valgrind-check/src/pub_sub/bin/z_pub_sub.rs

@@ -14,11 +14,10 @@
 use std::time::Duration;
 use zenoh::config::Config;
 use zenoh::prelude::r#async::*;
-use zenoh_util::init_log;
+
 #[tokio::main]
 async fn main() {
-
-    init_log();
+    zenoh_util::init_log_test();
 
     let _z = zenoh_runtime::ZRuntimePoolGuard;
 

ci/valgrind-check/src/queryable_get/bin/z_queryable_get.rs

@@ -15,11 +15,10 @@ use std::convert::TryFrom;
 use std::time::Duration;
 use zenoh::config::Config;
 use zenoh::prelude::r#async::*;
-use zenoh_util::init_log;
 
 #[tokio::main]
 async fn main() {
-    init_log();
+    zenoh_util::init_log_test();
 
     let _z = zenoh_runtime::ZRuntimePoolGuard;
 
@@ -36,9 +35,9 @@ async fn main() {
                 queryable_key_expr.clone(),
                 query.value().unwrap().clone(),
             ));
-            zenoh_runtime::ZRuntime::Application.block_in_place(
-                async move { query.reply(reply).res().await.unwrap(); }
-            );
+            zenoh_runtime::ZRuntime::Application.block_in_place(async move {
+                query.reply(reply).res().await.unwrap();
+            });
         })
         .complete(true)
         .res()

commons/zenoh-codec/tests/codec.rs

@@ -342,7 +342,7 @@ fn codec_shm_info() {
 // Common
 #[test]
 fn codec_extension() {
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     macro_rules! run_extension_single {
         ($ext:ty, $buff:expr) => {

commons/zenoh-util/Cargo.toml

@@ -33,6 +33,7 @@ maintenance = { status = "actively-developed" }
 
 [features]
 std = []
+test = []
 default = ["std"]
 
 [dependencies]

commons/zenoh-util/src/std_only/log.rs

@@ -1,16 +1,49 @@
+//
+// Copyright (c) 2024 ZettaScale Technology
+//
+// This program and the accompanying materials are made available under the
+// terms of the Eclipse Public License 2.0 which is available at
+// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
+// which is available at https://www.apache.org/licenses/LICENSE-2.0.
+//
+// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
+//
+// Contributors:
+//   ZettaScale Zenoh Team, <[email protected]>
+//
 use tracing_subscriber::EnvFilter;
 
 /// This is an utility function to enable the tracing formatting subscriber from
-/// the `RUST_LOG` environment variable.
+/// the `RUST_LOG` environment variable. If `RUST_LOG` is not set, then logging is not enabled.
 ///
 /// # Safety
 /// Calling this function initializes a `lazy_static` in the `tracing` crate
 /// such static is not deallocated prior to process existing, thus tools such as `valgrind`
 /// will report a memory leak.
 /// Refer to this issue: https://github.com/tokio-rs/tracing/issues/2069
-pub fn init_log_from_env() {
-    let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("z=info"));
+pub fn try_init_log_from_env() {
+    if let Ok(env_filter) = EnvFilter::try_from_default_env() {
+        init_env_filter(env_filter);
+    }
+}
+
+/// This is an utility function to enable the tracing formatting subscriber from
+/// the environment variable. If `RUST_LOG` is not set, then fallback directives are used.
+///
+/// # Safety
+/// Calling this function initializes a `lazy_static` in the `tracing` crate
+/// such static is not deallocated prior to process existing, thus tools such as `valgrind`
+/// will report a memory leak.
+/// Refer to this issue: https://github.com/tokio-rs/tracing/issues/2069
+pub fn init_log_from_env_or<S>(fallback: S)
+where
+    S: AsRef<str>,
+{
+    let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new(fallback));
+    init_env_filter(env_filter);
+}
 
+fn init_env_filter(env_filter: EnvFilter) {
     let subscriber = tracing_subscriber::fmt()
         .with_env_filter(env_filter)
         .with_thread_ids(true)
@@ -22,8 +55,11 @@ pub fn init_log_from_env() {
     let _ = tracing::subscriber::set_global_default(subscriber);
 }
 
-/// This is an utility function to enables the default tracing subscriber with INFO level
-pub fn init_log() {
+#[cfg(feature = "test")]
+// Used to verify memory leaks for valgrind CI.
+// `EnvFilter` internally uses a static reference that is not cleaned up yielding to false positive in valgrind.
+// This function enables logging without calling `EnvFilter` for env configuration.
+pub fn init_log_test() {
     let subscriber = tracing_subscriber::fmt()
         .with_max_level(tracing::Level::INFO)
         .with_thread_ids(true)

commons/zenoh-util/src/std_only/mod.rs

@@ -6,8 +6,7 @@ pub use lib_loader::*;
 pub mod timer;
 pub use timer::*;
 pub mod log;
-pub use log::init_log;
-pub use log::init_log_from_env;
+pub use log::*;
 
 /// The "ZENOH_HOME" environement variable name
 pub const ZENOH_HOME_ENV_VAR: &str = "ZENOH_HOME";

examples/examples/z_delete.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr) = parse_args();
 

examples/examples/z_forward.rs

@@ -20,7 +20,7 @@ use zenoh_ext::SubscriberForward;
 #[tokio::main]
 async fn main() {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, forward) = parse_args();
 

examples/examples/z_get.rs

@@ -21,7 +21,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, selector, value, target, timeout) = parse_args();
 

examples/examples/z_get_liveliness.rs

@@ -21,7 +21,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, timeout) = parse_args();
 

examples/examples/z_info.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let config = parse_args();
 

examples/examples/z_liveliness.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr) = parse_args();
 

examples/examples/z_ping.rs

@@ -20,7 +20,7 @@ use zenoh_examples::CommonArgs;
 
 fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, warmup, size, n) = parse_args();
     let session = zenoh::open(config).res().unwrap();

examples/examples/z_pong.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 
 fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let config = parse_args();
 

examples/examples/z_pub.rs

@@ -20,7 +20,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, value, attachment) = parse_args();
 

examples/examples/z_pub_shm.rs

@@ -24,7 +24,7 @@ const K: u32 = 3;
 #[tokio::main]
 async fn main() -> Result<(), zenoh::Error> {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (mut config, path, value) = parse_args();
 

examples/examples/z_pub_shm_thr.rs

@@ -21,7 +21,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
     let (mut config, sm_size, size) = parse_args();
 
     // A probing procedure for shared memory is performed upon session opening. To enable `z_pub_shm_thr` to operate

examples/examples/z_pub_thr.rs

@@ -20,7 +20,7 @@ use zenoh_examples::CommonArgs;
 
 fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
     let args = Args::parse();
 
     let mut prio = Priority::default();

examples/examples/z_pull.rs

@@ -20,7 +20,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr) = parse_args();
 

examples/examples/z_put.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, value) = parse_args();
 

examples/examples/z_put_float.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, value) = parse_args();
 

examples/examples/z_queryable.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, value, complete) = parse_args();
 

examples/examples/z_scout.rs

@@ -18,7 +18,7 @@ use zenoh::scouting::WhatAmI;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     println!("Scouting...");
     let receiver = zenoh::scout(WhatAmI::Peer | WhatAmI::Router, Config::default())

examples/examples/z_storage.rs

@@ -23,7 +23,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr, complete) = parse_args();
 

examples/examples/z_sub.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (mut config, key_expr) = parse_args();
 

examples/examples/z_sub_liveliness.rs

@@ -19,7 +19,7 @@ use zenoh_examples::CommonArgs;
 #[tokio::main]
 async fn main() {
     // Initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (config, key_expr) = parse_args();
 

examples/examples/z_sub_thr.rs

@@ -69,7 +69,7 @@ impl Drop for Stats {
 
 fn main() {
     // initiate logging
-    zenoh_util::init_log_from_env();
+    zenoh_util::try_init_log_from_env();
 
     let (mut config, m, n) = parse_args();