A small logging function to share between the client and server, inspired by winston

logger.js

/* This needs some work, and is probably pretty broken at the moment. Will come back to this later. */
define([
  'underscore'
], function (
  _
) {

  console.log(this);

  var root = this;

  var defaults = {
    // Methods that should be passed to `console`
    passMethods: [
      'assert', 'clear', 'count', 'dir', 'dirxml', 'exception', 'group',
      'groupCollapsed', 'groupEnd', 'profile', 'profileEnd', 'table', 'time',
      'timeEnd', 'trace'
    ],
    shouldPassMethods: true,
    logLevels: ['error', 'warn', 'info', 'debug', 'log'],
    logLevel: 'log',
    callback: null,
    transports: [root.console]
  };

  function Logger(options) {
    options = _.extend(defaults, options || {});
    this.passMethods = options.passMethods;
    this.shouldPassMethods = options.shouldPassMethods;
    this.logLevels = options.logLevels;
    this.logLevel = options.logLevel;
    this.callback = options.callback;
    this.transports = options.transports;

    for (var i=this.passMethods.length, method; i--;) {
      method = this.passMethods[i];
      this[method] = function () {
        if (this.shouldPassMethods && this.logLevel &&
            console && console[method]) {
          console[method].apply(console, arguments);
        }
      };
    }

    for (var l=this.logLevels.length, level; l--;) {
      level = this.logLevels[l];
      this[level] = function () {
        this.writeLog.apply(level, arguments);
        if (!this.isLevel(level)) return;
        for (var t=this.transports.length, transport; t--;) {
          transport = this.transports[t];
          transportFn = transport[level] || transport.log;
          if (transportFn) transportFn(arguments);
        }
      };
    }
  }

  Logger.prototype.isLevel = function (level) {
    if (_.isNaN(level)) level = _.indexOf(this.logLevels, level);
    return this.logLevel > level;
  };

  Logger.prototype.writeLog = function () {
    this.log.push(arguments);
  };

  return Logger;

});