LoggerJSON.Redactor behaviour (logger_json v7.0.3)

This module provides a behaviour which allows to redact sensitive information from logs.

Note: redactor will not be applied on Jason.Fragment structs if the encoder is Jason. For more information about encoding and redacting see LoggerJSON.Formatter.RedactorEncoder.encode/2.

Summary

Callbacks

new(opts)

Initializes a new redactor configuration.

redact(key, value, opts)

Takes a key and a value and returns a redacted value.

Callbacks

new(opts)

(optional)

@callback new(opts :: term()) :: {module(), term()}

Initializes a new redactor configuration.

Compile‑time vs. Runtime Configuration

This function can’t be used in config.exs because that file is evaluated before your application modules are compiled and loaded, so new/1 isn’t defined yet. You can only call it in config/runtime.exs or from your application code.

If you must set up the redactor in config.exs, use the tuple format: the first element is the module implementing LoggerJSON.Redactor, and the second is the options passed to new/1. For example:

config :logger, :default_handler,

formatter: {LoggerJSON.Formatters.Basic, redactors: [
  {MyRedactor, [option1: :value1]}
]}

Note that tuple‑based configs are resolved for each log entry, which can increase logging overhead.

redact(key, value, opts)

@callback redact(key :: String.t(), value :: term(), opts :: term()) :: term()

Takes a key and a value and returns a redacted value.

This callback will be applied on key-value pairs, like elements of structs, maps or keyword lists.