tracing-cloudwatch

tracing-cloudwatch is a custom tracing-subscriber layer that sends your application's tracing events(logs) to AWS CloudWatch Logs.

We have supported rusoto and the AWS SDK as AWS clients.

Usage

With AWS SDK

feature awssdk required

use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};

#[tokio::main]
async fn main() {
    let config = aws_config::load_defaults(aws_config::BehaviorVersion::latest()).await;
    let cw_client = aws_sdk_cloudwatchlogs::Client::new(&config);

    tracing_subscriber::registry::Registry::default()
        .with(
            tracing_cloudwatch::layer().with_client(
                cw_client,
                tracing_cloudwatch::ExportConfig::default()
                    .with_batch_size(5)
                    .with_interval(std::time::Duration::from_secs(1))
                    .with_log_group_name("tracing-cloudwatch")
                    .with_log_stream_name("stream-1"),
            )
            .with_code_location(true)
            .with_target(false),
        )
        .init();
}

Chronological order

When aggregating logs from multiple places (or integrations such as tracing-gstreamer), messages can become unordered. This causes a InvalidParameterException: Log events in a single PutLogEvents request must be in chronological order. error from the CloudWatch client. To mediate this, you may enable the ordered_logs feature. Take into consideration that this can possibly increase processing time significantly depending on the number of events in the batch. Your milage may vary!

There is some additional context in https://github.com/ymgyt/tracing-cloudwatch/issues/40

With Rusoto

feature rusoto required

use tracing_subscriber::{layer::SubscriberExt, util::SubscriberInitExt};

#[tokio::main]
async fn main() {
    let cw_client = rusoto_logs::CloudWatchLogsClient::new(rusoto_core::Region::ApNortheast1);

    tracing_subscriber::registry::Registry::default()
        .with(
            tracing_cloudwatch::layer().with_client(
                cw_client,
                tracing_cloudwatch::ExportConfig::default()
                    .with_batch_size(5)
                    .with_interval(std::time::Duration::from_secs(1))
                    .with_log_group_name("tracing-cloudwatch")
                    .with_log_stream_name("stream-1"),
            )
            .with_code_location(true)
            .with_target(false),
        )
        .init();
}

Using pre-configured tracing_subsriber::fmt::Layer

You can specify a pre-configured fmt::Layer to control the log format. For example, the following example outputs the logs in JSON format.

tracing_subscriber::registry::Registry::default()
    .with(tracing_cloudwatch::layer()
        .with_fmt_layer(
            tracing_subscriber::fmt::layer()
                .json()
                .without_time()
        )
    )
    .init();

Required Permissions

Currently, following AWS IAM Permissions required

• logs:PutLogEvents

CloudWatch Log Groups and Streams

This crate does not create a log group and log stream, so if the specified log group and log stream does not exist, it will raise an error.

Retry and Timeout

We haven't implemented any custom retry logic or timeout settings within the crate. We assume that these configurations are handled through the SDK Client.
For instance, in the AWS SDK, you can set up these configurations using timeout_config and retry_config

License

This project is licensed under the MIT license.