logger.js

var winston = require('winston')
// set default log level.
var logLevel = 'debug'
// Set up logger
var logger = winston.createLogger({
    level: logLevel,
    exitOnError: false,
    transports: [
        new (winston.transports.Console)(),
        new (winston.transports.File)({ filename: 'app.log' })
    ]
})
// Extend logger object to properly log 'Error' types
var origLog = logger.log
logger.log = function (level, msg) {
    if (msg instanceof Error) {
        var args = Array.prototype.slice.call(arguments)
        args[1] = msg.stack
        origLog.apply(logger, args)
    } else {
        origLog.apply(logger, arguments)
    }
}
module.exports = logger