observability: tracing gum, automatically cross ref traceID (#5079)

* add some gum

* bump expander

* gum

* fix all remaining issues

* last fixup

* Update node/gum/proc-macro/src/lib.rs

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* change

* netowrk

* fixins

* chore

* allow optional fmt str + args, prep for expr as kv field

* tracing -> gum rename fallout

* restrict further

* allow multiple levels of field accesses

* another round of docs and a slip of the pen

* update ADR

* fixup lock fiel

* use target: instead of target=

* minors

* fix

* chore

* Update node/gum/README.md

Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: Andrei Sandu <54316454+sandreim@users.noreply.github.com>

polkadot/node/core/pvf/src/prepare/pool.rs

@@ -201,7 +201,7 @@ fn handle_to_pool(
 ) {
 	match to_pool {
 		ToPool::Spawn => {
-			tracing::debug!(target: LOG_TARGET, "spawning a new prepare worker");
+			gum::debug!(target: LOG_TARGET, "spawning a new prepare worker");
 			metrics.prepare_worker().on_begin_spawn();
 			mux.push(spawn_worker_task(program_path.to_owned(), spawn_timeout).boxed());
 		},
@@ -234,7 +234,7 @@ fn handle_to_pool(
 			}
 		},
 		ToPool::Kill(worker) => {
-			tracing::debug!(target: LOG_TARGET, ?worker, "killing prepare worker");
+			gum::debug!(target: LOG_TARGET, ?worker, "killing prepare worker");
 			// It may be absent if it were previously already removed by `purge_dead`.
 			let _ = attempt_retire(metrics, spawned, worker);
 		},
@@ -248,7 +248,7 @@ async fn spawn_worker_task(program_path: PathBuf, spawn_timeout: Duration) -> Po
 		match worker::spawn(&program_path, spawn_timeout).await {
 			Ok((idle, handle)) => break PoolEvent::Spawn(idle, handle),
 			Err(err) => {
-				tracing::warn!(target: LOG_TARGET, "failed to spawn a prepare worker: {:?}", err);
+				gum::warn!(target: LOG_TARGET, "failed to spawn a prepare worker: {:?}", err);
 
 				// Assume that the failure intermittent and retry after a delay.
 				Delay::new(Duration::from_secs(3)).await;

polkadot/node/core/pvf/src/prepare/queue.rs

@@ -211,7 +211,7 @@ async fn handle_to_queue(queue: &mut Queue, to_queue: ToQueue) -> Result<(), Fat
 }
 
 async fn handle_enqueue(queue: &mut Queue, priority: Priority, pvf: Pvf) -> Result<(), Fatal> {
-	tracing::debug!(
+	gum::debug!(
 		target: LOG_TARGET,
 		validation_code_hash = ?pvf.code_hash,
 		?priority,
@@ -228,7 +228,7 @@ async fn handle_enqueue(queue: &mut Queue, priority: Priority, pvf: Pvf) -> Resu
 		// Precondtion for `Enqueue` is that it is sent only once for a PVF;
 		// Thus this should always be `false`;
 		// qed.
-		tracing::warn!(
+		gum::warn!(
 			target: LOG_TARGET,
 			"duplicate `enqueue` command received for {:?}",
 			artifact_id,
@@ -331,7 +331,7 @@ async fn handle_worker_concluded(
 
 	queue.artifact_id_to_job.remove(&artifact_id);
 
-	tracing::debug!(
+	gum::debug!(
 		target: LOG_TARGET,
 		validation_code_hash = ?artifact_id.code_hash,
 		?worker,
@@ -370,7 +370,7 @@ async fn handle_worker_concluded(
 }
 
 async fn handle_worker_rip(queue: &mut Queue, worker: Worker) -> Result<(), Fatal> {
-	tracing::debug!(target: LOG_TARGET, ?worker, "prepare worker ripped");
+	gum::debug!(target: LOG_TARGET, ?worker, "prepare worker ripped");
 
 	let worker_data = queue.workers.remove(worker);
 	if let Some(WorkerData { job: Some(job), .. }) = worker_data {

polkadot/node/core/pvf/src/prepare/worker.rs

@@ -72,7 +72,7 @@ pub async fn start_work(
 ) -> Outcome {
 	let IdleWorker { mut stream, pid } = worker;
 
-	tracing::debug!(
+	gum::debug!(
 		target: LOG_TARGET,
 		worker_pid = %pid,
 		"starting prepare for {}",
@@ -81,7 +81,7 @@ pub async fn start_work(
 
 	with_tmp_file(pid, cache_path, |tmp_file| async move {
 		if let Err(err) = send_request(&mut stream, code, &tmp_file).await {
-			tracing::warn!(
+			gum::warn!(
 				target: LOG_TARGET,
 				worker_pid = %pid,
 				"failed to send a prepare request: {:?}",
@@ -109,7 +109,7 @@ pub async fn start_work(
 					// By convention we expect encoded `PrepareResult`.
 					if let Ok(result) = PrepareResult::decode(&mut response_bytes.as_slice()) {
 						if result.is_ok() {
-							tracing::debug!(
+							gum::debug!(
 								target: LOG_TARGET,
 								worker_pid = %pid,
 								"promoting WIP artifact {} to {}",
@@ -121,7 +121,7 @@ pub async fn start_work(
 								.await
 								.map(|_| Selected::Done(result))
 								.unwrap_or_else(|err| {
-									tracing::warn!(
+									gum::warn!(
 										target: LOG_TARGET,
 										worker_pid = %pid,
 										"failed to rename the artifact from {} to {}: {:?}",
@@ -137,7 +137,7 @@ pub async fn start_work(
 					} else {
 						// We received invalid bytes from the worker.
 						let bound_bytes = &response_bytes[..response_bytes.len().min(4)];
-						tracing::warn!(
+						gum::warn!(
 							target: LOG_TARGET,
 							worker_pid = %pid,
 							"received unexpected response from the prepare worker: {}",
@@ -148,7 +148,7 @@ pub async fn start_work(
 				},
 				Ok(Err(err)) => {
 					// Communication error within the time limit.
-					tracing::warn!(
+					gum::warn!(
 						target: LOG_TARGET,
 						worker_pid = %pid,
 						"failed to recv a prepare response: {:?}",
@@ -184,7 +184,7 @@ where
 	let tmp_file = match tmpfile_in("prepare-artifact-", cache_path).await {
 		Ok(f) => f,
 		Err(err) => {
-			tracing::warn!(
+			gum::warn!(
 				target: LOG_TARGET,
 				worker_pid = %pid,
 				"failed to create a temp file for the artifact: {:?}",
@@ -205,7 +205,7 @@ where
 		Ok(()) => (),
 		Err(err) if err.kind() == std::io::ErrorKind::NotFound => (),
 		Err(err) => {
-			tracing::warn!(
+			gum::warn!(
 				target: LOG_TARGET,
 				worker_pid = %pid,
 				"failed to remove the tmp file: {:?}",
@@ -246,7 +246,7 @@ pub fn worker_entrypoint(socket_path: &str) {
 		loop {
 			let (code, dest) = recv_request(&mut stream).await?;
 
-			tracing::debug!(
+			gum::debug!(
 				target: LOG_TARGET,
 				worker_pid = %std::process::id(),
 				"worker: preparing artifact",
@@ -267,7 +267,7 @@ pub fn worker_entrypoint(socket_path: &str) {
 
 					let artifact_bytes = compiled_artifact.encode();
 
-					tracing::debug!(
+					gum::debug!(
 						target: LOG_TARGET,
 						worker_pid = %std::process::id(),
 						"worker: writing artifact to {}",