Advanced logging controls (#830)

* Implement Lambda's advance logging controls.

Provide a feature that exposes a initialization function for `tracing-subscriber` that sets the right logging controls based on Lambda's configuration.
The feature is enabled by default, but it can be disabled if a user doesn't want to use it.

Signed-off-by: David Calavera <[email protected]>

* Update examples to use the new tracing-subscriber feature.

Signed-off-by: David Calavera <[email protected]>

* Remove tracing from the runtime client.

It makes logs too verbose.

Signed-off-by: David Calavera <[email protected]>

* Make the tracing dependency optional.

Signed-off-by: David Calavera <[email protected]>

* Fix ambiguous name in old versions of Rust.

Identify the dependency as the top dependency.

Signed-off-by: David Calavera <[email protected]>

* Fix formatting.

Signed-off-by: David Calavera <[email protected]>

---------

Signed-off-by: David Calavera <[email protected]>

Author: calavera

README.md

@@ -372,6 +372,24 @@ You can read more about how [cargo lambda watch](https://www.cargo-lambda.info/c
 
 Lambdas can be run and debugged locally using a special [Lambda debug proxy](https://github.com/rimutaka/lambda-debug-proxy) (a non-AWS repo maintained by @rimutaka), which is a Lambda function that forwards incoming requests to one AWS SQS queue and reads responses from another queue. A local proxy running on your development computer reads the queue, calls your Lambda locally and sends back the response. This approach allows debugging of Lambda functions locally while being part of your AWS workflow. The Lambda handler code does not need to be modified between the local and AWS versions.
 
+## Tracing and Logging
+
+The Rust Runtime for Lambda integrates with the (Tracing)[https://tracing.rs] libraries to provide tracing and logging.
+
+By default, the runtime emits `tracing` events that you can collect via `tracing-subscriber`. It also enabled a feature called `tracing` that exposes a default subsriber with sensible options to send logging information to AWS CloudWatch. Follow the next example that shows how to enable the default subscriber:
+
+```rust
+use lambda_runtime::{run, service_fn, tracing, Error};
+
+#[tokio::main]
+async fn main() -> Result<(), Error> {
+    tracing::init_default_subscriber();
+    run(service_fn(|event| tracing::info!(?event))).await
+}
+```
+
+The subscriber uses `RUST_LOG` as the environment variable to determine the log level for your function. It also uses [Lambda's advance logging controls](https://aws.amazon.com/blogs/compute/introducing-advanced-logging-controls-for-aws-lambda-functions/) if they're configured for your function. By default, the log level to emit events is `INFO`.
+
 ## AWS event objects
 
 This project includes Lambda event struct definitions, [`aws_lambda_events`](https://crates.io/crates/aws_lambda_events). This crate can be leveraged to provide strongly-typed Lambda event structs. You can create your own custom event objects and their corresponding structs as well.

examples/advanced-sqs-multiple-functions-shared-data/consumer/Cargo.toml

@@ -3,19 +3,14 @@ name = "consumer"
 version = "0.1.0"
 edition = "2021"
 
-
 [dependencies]
-#tracing
-tracing = "0.1.40"
-tracing-subscriber = "0.3.17"
-
 #aws dependencies
 aws-sdk-config = "0.35.0"
 aws-sdk-sqs = "0.35.0"
 aws_lambda_events = { version = "0.11.1", features = ["sqs"], default-features = false }
 
 #lambda runtime
-lambda_runtime = "0.8.1"
+lambda_runtime = { path = "../../../lambda-runtime" }
 tokio = { version = "1", features = ["macros"] }
 
 #shared lib

examples/advanced-sqs-multiple-functions-shared-data/consumer/src/main.rs

@@ -1,15 +1,10 @@
 use aws_lambda_events::event::sqs::SqsEventObj;
-use lambda_runtime::{service_fn, Error, LambdaEvent};
+use lambda_runtime::{service_fn, tracing, Error, LambdaEvent};
 use pizza_lib::Pizza;
 
 #[tokio::main]
 async fn main() -> Result<(), Error> {
-    tracing_subscriber::fmt()
-        .with_max_level(tracing::Level::INFO)
-        .with_target(false)
-        .with_ansi(false)
-        .without_time()
-        .init();
+    tracing::init_default_subscriber();
     let func = service_fn(func);
     lambda_runtime::run(func).await?;
     Ok(())
@@ -18,7 +13,7 @@ async fn main() -> Result<(), Error> {
 async fn func(event: LambdaEvent<SqsEventObj<Pizza>>) -> Result<(), Error> {
     for record in event.payload.records.iter() {
         let pizza = &record.body;
-        println!("Pizza name: {} with toppings: {:?}", pizza.name, pizza.toppings);
+        tracing::info!(name = pizza.name, toppings = ?pizza.toppings, "pizza order received");
     }
     Ok(())
 }

examples/advanced-sqs-multiple-functions-shared-data/producer/Cargo.toml

@@ -7,17 +7,13 @@ edition = "2021"
 env = { "QUEUE_URL" = "https://changeMe" } 
 
 [dependencies]
-#tracing
-tracing = "0.1.40"
-tracing-subscriber = "0.3.17"
-
 #aws dependencies
 aws-config = "0.57.1"
 aws-sdk-config = "0.35.0"
 aws-sdk-sqs = "0.35.0"
 
 #lambda runtime
-lambda_runtime = "0.8.1"
+lambda_runtime = { path = "../../../lambda-runtime" }
 serde_json = "1.0.108"
 tokio = { version = "1", features = ["macros"] }
 

examples/advanced-sqs-multiple-functions-shared-data/producer/src/main.rs

@@ -1,4 +1,4 @@
-use lambda_runtime::{service_fn, Error, LambdaEvent};
+use lambda_runtime::{service_fn, tracing, Error, LambdaEvent};
 use pizza_lib::Pizza;
 use serde_json::{json, Value};
 
@@ -15,12 +15,7 @@ impl SQSManager {
 
 #[tokio::main]
 async fn main() -> Result<(), Error> {
-    tracing_subscriber::fmt()
-        .with_max_level(tracing::Level::INFO)
-        .with_target(false)
-        .with_ansi(false)
-        .without_time()
-        .init();
+    tracing::init_default_subscriber();
 
     // read the queue url from the environment
     let queue_url = std::env::var("QUEUE_URL").expect("could not read QUEUE_URL");
@@ -31,9 +26,7 @@ async fn main() -> Result<(), Error> {
     let sqs_manager_ref = &sqs_manager;
 
     // no need to create a SQS Client for each incoming request, let's use a shared state
-    let handler_func_closure = |event: LambdaEvent<Value>| async move {
-        process_event(event, sqs_manager_ref).await
-    };
+    let handler_func_closure = |event: LambdaEvent<Value>| async move { process_event(event, sqs_manager_ref).await };
     lambda_runtime::run(service_fn(handler_func_closure)).await?;
     Ok(())
 }

examples/advanced-sqs-partial-batch-failures/Cargo.toml

@@ -12,5 +12,3 @@ aws_lambda_events = { path = "../../lambda-events" }
 lambda_runtime = { path = "../../lambda-runtime" }
 tokio = { version = "1", features = ["macros"] }
 futures = "0.3"
-tracing = { version = "0.1", features = ["log"] }
-tracing-subscriber = { version = "0.3", default-features = false, features = ["fmt"] }

examples/advanced-sqs-partial-batch-failures/src/main.rs

@@ -3,9 +3,12 @@ use aws_lambda_events::{
     sqs::{BatchItemFailure, SqsBatchResponse, SqsMessageObj},
 };
 use futures::Future;
-use lambda_runtime::{run, service_fn, Error, LambdaEvent};
+use lambda_runtime::{
+    run, service_fn,
+    tracing::{self, Instrument},
+    Error, LambdaEvent,
+};
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
-use tracing::Instrument;
 
 /// [To customize] Your object definition, sent to the SQS queue triggering this lambda.
 #[derive(Deserialize, Serialize)]
@@ -29,13 +32,7 @@ async fn data_handler(data: Data) -> Result<(), Error> {
 #[tokio::main]
 async fn main() -> Result<(), Error> {
     // required to enable CloudWatch error logging by the runtime
-    tracing_subscriber::fmt()
-        .with_max_level(tracing::Level::INFO)
-        // disable printing the name of the module in every log line.
-        .with_target(false)
-        // disabling time is handy because CloudWatch will add the ingestion time.
-        .without_time()
-        .init();
+    tracing::init_default_subscriber();
 
     run_sqs_partial_batch_failure(data_handler).await
 }

examples/basic-error-handling/Cargo.toml

@@ -3,20 +3,9 @@ name = "error-handling"
 version = "0.1.0"
 edition = "2021"
 
-
-# Use cargo-edit(https://github.com/killercup/cargo-edit#installation)
-# to manage dependencies.
-# Running `cargo add DEPENDENCY_NAME` will
-# add the latest version of a dependency to the list,
-# and it will keep the alphabetic ordering for you.
-
 [dependencies]
 lambda_runtime = { path = "../../lambda-runtime" }
 serde = "1.0.136"
 serde_json = "1.0.81"
 simple-error = "0.2.3"
 tokio = { version = "1", features = ["macros"] }
-tracing = { version = "0.1", features = ["log"] }
-tracing-subscriber = { version = "0.3", default-features = false, features = ["fmt"] }
-
-

examples/basic-error-handling/src/main.rs

@@ -1,5 +1,5 @@
 /// See https://github.com/awslabs/aws-lambda-rust-runtime for more info on Rust runtime for AWS Lambda
-use lambda_runtime::{service_fn, Error, LambdaEvent};
+use lambda_runtime::{service_fn, tracing, Error, LambdaEvent};
 use serde::{Deserialize, Serialize};
 use serde_json::{json, Value};
 use std::fs::File;
@@ -50,13 +50,7 @@ impl std::fmt::Display for CustomError {
 #[tokio::main]
 async fn main() -> Result<(), Error> {
     // required to enable CloudWatch error logging by the runtime
-    tracing_subscriber::fmt()
-        .with_max_level(tracing::Level::INFO)
-        // disable printing the name of the module in every log line.
-        .with_target(false)
-        // disabling time is handy because CloudWatch will add the ingestion time.
-        .without_time()
-        .init();
+    tracing::init_default_subscriber();
 
     // call the actual handler of the request
     let func = service_fn(func);

examples/basic-lambda-external-runtime/Cargo.toml

@@ -6,10 +6,9 @@ edition = "2021"
 [dependencies]
 async-channel = "1.8.0"
 futures-lite = "1.13.0"
-lambda_runtime = "0.8.0"
-lambda_runtime_api_client = "0.8.0"
+lambda_runtime = { path = "../../lambda-runtime" }
 serde = "1.0.163"
 tokio = "1.28.2"
+
+[dev-dependencies]
 tokio-test = "0.4.2"
-tracing = "0.1.37"
-tracing-subscriber = { version = "0.3", default-features = false, features = ["fmt"] }