logger.js

var env = process.env.NODE_ENV || 'dev';
var winston = require('winston');

winston.setLevels(winston.config.syslog.levels)

if (env !== 'dev') {
  winston.remove(winston.transports.Console);
}

var customColors = {
  trace: 'white',
  debug: 'green',
  info: 'green',
  warn: 'yellow',
  crit: 'red',
  fatal: 'red'
};

var logger = new (winston.Logger)({
  colors: customColors,
  levels: {
    trace: 0,
    debug: 1,
    info: 2,
    warn: 3,
    crit: 4,
    fatal: 5
  },
  transports: [
    // Console.
    new (winston.transports.Console)({
      colorize: true,
      timestamp: true
    }),
    // File.
    new (winston.transports.File)({
      filename: './logs/node.log',
      level: 'info',
      timestamp: true,
      json: false,
      maxsize: 100000,
      maxFiles: 5,
    })
  ]
});
winston.addColors(customColors);

module.exports = logger;