docs/go/observability/logging.md
Encore offers built-in support for Structured Logging, which combines a free-form log message with structured and type-safe key-value pairs. This enables straightforward analysis of what your application is doing, in a way that is easy for a computer to parse, analyze, and index. This makes it simple to quickly filter and search through logs.
Encore’s logging is integrated with the built-in Distributed Tracing functionality, and all logs are automatically included in the active trace. This dramatically simplifies debugging of your application.
First, import encore.dev/rlog in your package. Then simply call one of the package methods Info, Error, or Debug. For example:
rlog.Info("log message",
"user_id", 12345,
"is_subscriber", true)
rlog.Error("something went terribly wrong!",
"err", err)
The first parameter is the log message. After that follows zero or more key-value pairs for structured logging for context.
If you’re logging many log messages with the same key-value pairs each time it can be a bit cumbersome. To help with that, use rlog.With() to group them into a context object, which then copies the key-value pairs into each log event:
ctx := rlog.With("is_subscriber", true)
ctx.Info("user logged in", "login_method", "oauth") // includes is_subscriber=true
For more information, see the API Documentation.
Encore also makes it simple to live-stream logs directly to your terminal, from any environment, by running:
$ encore logs --env=prod