Introduction

The logging packages of Meziantou.Framework are providers for Microsoft.Extensions.Logging. Your code keeps logging through ILogger and ILogger<T>; the provider decides where the entries go.

Each package is independent: install only the ones you need. The test packages are often used together: the in-memory logger to assert on the entries, and the xUnit.net logger to read them when a test fails.

What you can do with them

• Write the logs to files without blocking the application, with one file per hour, day or month, a size limit, retention and compression. See File logger.
• Assert on the logs in tests: find the entries by level, message, category or parameter value. See In-memory logger.
• Show the logs in the test output, for the test that is running, including from a host or a web application started by the test. See xUnit.net logger.

Namespaces

LoggerFactory, ILogger and the LogInformation extension methods are in the Microsoft.Extensions.Logging namespace.

Related sections

• Snapshot testing and Inline snapshot testing compare the entries collected by the in-memory logger with a snapshot instead of writing one assertion per entry.
• OpenTelemetry collector receives the logs, traces and metrics that an application exports with OpenTelemetry, to test them.

Next steps

• Getting started: install a package and write your first log entry.