Logging

The CLI embraces the swift-log interface for logging. The package abstracts away the implementation details of logging, allowing the CLI to be agnostic to the logging backend. The logger is dependency-injected using swift-service-context and can be accessed anywhere using:

ServiceContext.current?.logger

NOTE

swift-service-context passes the instance using task locals which don't propagate the value when using Dispatch, so if you run asynchronous code using Dispatch, you'll to get the instance from the context and pass it to the asynchronous operation.

What to log

Logs are not the CLI's UI. They are a tool to diagnose issues when they arise. Therefore, the more information you provide, the better. When building new features, put yourself in the shoes of a developer coming across unexpected behavior, and think about what information would be helpful to them. Ensure you you use the right log level. Otherwise developers won't be able to filter out the noise.