View Source Logger.Translator behaviour (Logger v1.18.0)

Default translation for Erlang log messages.

Logger allows developers to rewrite log messages provided by OTP applications into a format more compatible with Elixir log messages by providing a translator.

A translator is simply a tuple containing a module and a function that can be added and removed via the Logger.add_translator/1 and Logger.remove_translator/1 functions and is invoked for every Erlang message above the minimum log level with four arguments:

  • min_level - the current Logger level
  • level - the level of the message being translated
  • kind - if the message is a :report or :format
  • message - the message to format. If it is :report, it is a tuple with {report_type, report_data}, if it is :format, it is a tuple with {format_message, format_args}.

The function must return:

  • {:ok, chardata, metadata} - if the message translation with its metadata
  • {:ok, chardata} - the translated message
  • :skip - if the message is not meant to be translated nor logged
  • :none - if there is no translation, which triggers the next translator

See the function translate/4 in this module for an example implementation and the default messages translated by Logger.

Summary

Callbacks

Callback for translating a logger message.

Functions

Built-in translation function.

Callbacks

translate(level, level, arg3, report)

@callback translate(Logger.level(), Logger.level(), :format | :report, :logger.report()) ::
  {:ok, iodata(), keyword()} | {:ok, iodata()} | :skip | :none

Callback for translating a logger message.

Functions

translate(min_level, level, kind, message)

Built-in translation function.

This function is an implementation of the translate/4 callback. For arguments and return value of this function, see that callback.