molindo-node-logger

A Node.js logger that integrates well with the Molindo infrastructure.

Features

• Pretty prints messages in development mode.
• Prints JSON messages in production mode.
• Errors are printed to stderr, while all other levels are printed to stdout.
• In development only infos, warnings and errors are printed, while in production all levels are printed.
• If the process encounters an error, it will log it to the console before shutting down. unhandledRejection errors thrown from promises are logged as well.
• Offers an express integration that logs HTTP requests, including the operationName in the case of GraphQL requests. Confidential headers like cookie or authorization are masked.
• Uses the levels and level values from logback: ERROR (40000), WARN (30000), INFO (20000), DEBUG (10000), TRACE (5000).

Usage

import Logger from 'molindo-node-logger';

const logger = new Logger({ service: 'pizza-shop' });
logger.trace('Making a salami pizza …');
logger.debug('Adding salami …');
logger.info('Putting it in the oven …');
logger.warn("Don't forget to get it out in time …");
logger.error('Oh no, the pizza is burned!');

In production, printed JSON will look like this (except that it's not pretty printed):

{
  "service": "pizza-shop",
  "@timestamp": "2017-10-19T08:26:13.168Z",
  "level": "INFO",
  "level_value": 20000,
  "message": "Pizza is ready!"
}

Express integration

If you're running an express server, you can register the logger middleware to log HTTP requests.

import express from 'express';
import Logger, { createLoggerMiddleware } from 'molindo-node-logger';

const server = express();

const logger = new Logger({ service: 'pizza-shop' });
server.use(createLoggerMiddleware({ logger }));