@5app/logger

logger

Simple console logger that outputs json in prod and pretty messages on dev

Usage

npm install --save @5app/logger

Then, generate a logger in your app and use it to log messages.

const getLogger = require('@5app/logger');

const logger = getLogger({
  simple: process.env.NODE_ENV === 'development',
  metadata: {
    tag: process.env.TAG, // release tag, e.g. docker container tag
  },
});

logger.info('An email was sent', {
  email: '[e-mail]',
  template: 'template1',
});

logger.error(new Error('Unknown playlist 123'));

Options

The logger generator accepts the following options:

simple

This boolean value specifies whether we should log pretty dev-friendly messages instead of JSON or not. By default, simple will be false.

Example:

const getLogger = require('@5app/logger');

// This logger will log dev-friendly messages
const logger = getLogger({
  simple: true,
});

metadata

Metadata is an object containing service metadata like the release tag or the A/B testing experiment we are running. This object will be added to each log entry when using the JSON mode.

Example:

const getLogger = require('@5app/logger');

// This logger will add details about the current release and A/B experiment to every log line
const getLogger = require('@5app/logger');
const logger = getLogger({
  metadata: {
    release: '1.2.3',
    experiment: 12345,
  },
});

Changelog

1.0.1 (2019-09-10)

Bug Fixes

• Ignore metadata in simple mode (1779e1c)