@gasket/plugin-logger

This plugin adds a logger to your Gasket application and introduces lifecycles for custom logger implementations. This plugin is included by default in all Gasket applications.

At this time, there is only one plugin which implements a custom logger: @gasket/plugin-winston.

Configuration

Configuration for @gasket/plugin-logger lives under the logger key in gasket.config.

| Option | Type | Default | Description | |---|---|---|---| | overrideConsole | boolean | false | When true, replaces the global console methods (log, info, warn, error, debug) with calls to gasket.logger. |

overrideConsole

Note: overrideConsole only takes effect when a custom logger is registered via the createLogger lifecycle; it has no effect when the default console-based fallback logger is in use.

Some third-party packages (e.g. SDKs, component libraries) call console.* directly and bypass the configured logger pipeline entirely. This causes issues such as multi-line plain-text output appearing in structured log aggregators (e.g. Elastic) instead of properly formatted log entries, because the formatting, transport, and metadata configuration in gasket.logger is never applied.

Enabling overrideConsole patches the global console methods during the init lifecycle — early enough to capture all subsequent output — and routes them through gasket.logger, so log levels, structured metadata, and transports work consistently across the entire app.

// gasket.config.js
export default {
  logger: {
    overrideConsole: true
  }
};

Note: This is an opt-in stop-gap for apps where third-party dependencies cannot be updated to accept a custom logger instance. The preferred long-term solution is to update those libraries to accept a logger instance so that gasket.logger can be passed down directly.

Installation

This plugin is only used by presets for create-gasket-app and is not installed for apps.

Actions

getLogger

Get the logger instance using the Actions API.

const logger = gasket.actions.getLogger();

Lifecycles

createLogger

To implement a custom logger, hook the createLogger lifecycle. Your hook must be synchronous and return an object with this shape:

type Logger = {
  [level: string]: (...args: Array<any>) => void,
  child: (metadata: Object) => Logger,
  close?: () => Promise<void> // Optional
}

The level keys are the log levels that your logger supports. The values are functions that accept any number of arguments and write them to the log. Your logger must support, at minimum, the following levels:

• debug
• error
• info
• warn

The child function is used to create a new logger with additional metadata. The metadata argument is set of properties that will be included in every log entry. The child function must return a new logger with the same shape as the parent logger.

The close function, if supplied, is called when the application is shutting down and should be used to close any open resources.

Test

If you are contributing to this plugin, use the following to run the tests:

npm test

License

MIT