LocalStack supports logging output and error reporting through the
localstack CLI or a Docker/Docker Compose based setup. LocalStack’s logging setup allows you to:
- Discover errors in your code during development & testing.
- Get visibility into how and why your API calls are failing.
- Figure out unexpected errors such as Lambda timeouts and more!
With LocalStack logging, you can easily retrieve additional detail around errors using various configuration variables to specify the verbosity and the log level.
You can explicitly set a log level via two configuration variables:
LS_LOG. You can configure them while starting the LocalStack container, either with the CLI or a Docker/Docker-Compose setup.
DEBUG can be either
0 is the default). With
DEBUG, you can print more verbose logs, useful for troubleshooting issues. With
DEBUG=1, errors inside LocalStack are reported to the client in full, and these stack traces can help you better triage your issues.
LS_LOG supports the following values:
LS_LOG affects the log handlers level directly. If
LS_LOG is configured as
trace-internal, it will automatically set
DEBUG=1. To retrieve the debug information, it is recommended to set
DEBUG=1. While configuring
trace-internal, the LocalStack container will report the same log format but append the request and response objects and the HTTP headers to the log line.
AWS requests are logged uniformly in the
INFO log level (set by default or when
DEBUG=0). The shape is
AWS <service>.<operation> => <http-status> (<error type>). Requests to HTTP endpoints are logged in a similar way.
2022-07-12T10:12:03.250 INFO --- [ asgi_gw_0] localstack.request.aws : AWS s3.PutObject => 404 (NoSuchBucket) 2022-07-12T10:12:11.295 INFO --- [ asgi_gw_0] localstack.request.aws : AWS s3.CreateBucket => 200 2022-07-12T10:12:13.159 INFO --- [ asgi_gw_1] localstack.request.aws : AWS s3.PutObject => 200 2022-07-12T10:12:28.761 INFO --- [ asgi_gw_0] localstack.request.http : GET /_localstack/health => 200
You can inspect the logs of the LocalStack container using the
localstack CLI or your Docker/Docker Compose setup. With the
localstack CLI, you can run the following command to inspect the logs of the LocalStack container:
$ localstack logs
With Docker/Docker-Compose, you can run
docker ps to get the container ID of the LocalStack container and then run
docker logs <container-id> to inspect the logs.
To view the logs via a user interface, you can use the following options: