A super easy logger wrapper for making dumb js frameworks less dumb. By all means steal this. Please.

logger.coffee

root = exports ? this
root.Logger =
class Logger
  constructor: (options = {}) ->
    @mapping = options.mapping ? {
      error: (message) ->
        console.error.call console, message
      warn: (message) ->
        console.warn.call console, message
      info: (message) ->
        console.info.call console, message
      debug: (message) ->
        console.debug.call console, message
    }
    @prefixText = options.prefixText ? null
    @includePrefix = options.includePrefix ? false
    @includeLevel = options.includeLevel ? true
    @level = options.level ? 4
  error: (message, params) ->
    prefix = level = ""
    prefix = "[#{@prefixText}]" if @includePrefix
    level = "[ERROR]" if @includeLevel
    if params
      for param in params
        message = "#{message}\n\t#{JSON.stringify param }"
    @mapping.error "#{prefix} #{level} #{message}" if @level > 0

  warn: (message, params) ->
    prefix = level = ""
    prefix = "[#{@prefixText}]" if @includePrefix
    level = "[ERROR]" if @includeLevel
    if params
      for param in params
        message = "#{message}\n\t#{JSON.stringify param }"
    @mapping.warn "#{prefix} #{level} #{message}" if @level > 1

  info: (message, params) ->
    prefix = level = ""
    prefix = "[#{@prefixText}]" if @includePrefix
    level = "[ERROR]" if @includeLevel
    if params
      for param in params
        message = "#{message}\n\t#{JSON.stringify param }"
    @mapping.info "#{prefix} #{level} #{message}" if @level > 2

  debug: (message, params) ->
    prefix = level = ""
    prefix = "[#{@prefixText}]" if @includePrefix
    level = "[ERROR]" if @includeLevel
    if params
      for param in params
        message = "#{message}\n\t#{JSON.stringify param }"
    @mapping.debug "#{prefix} #{level} #{message}" if @level > 3

  setLevel: (level) ->
    @level = level

  getLevel: () ->
    @level

logger.js

// Generated by CoffeeScript 1.6.2
(function() {
  var Logger, root;

  root = typeof exports !== "undefined" && exports !== null ? exports : this;

  root.Logger = Logger = (function() {
    function Logger(options) {
      var _ref, _ref1, _ref2, _ref3, _ref4;

      if (options == null) {
        options = {};
      }
      this.mapping = (_ref = options.mapping) != null ? _ref : {
        error: function(message) {
          return console.error.call(console, message);
        },
        warn: function(message) {
          return console.warn.call(console, message);
        },
        info: function(message) {
          return console.info.call(console, message);
        },
        debug: function(message) {
          return console.debug.call(console, message);
        }
      };
      this.prefixText = (_ref1 = options.prefixText) != null ? _ref1 : null;
      this.includePrefix = (_ref2 = options.includePrefix) != null ? _ref2 : false;
      this.includeLevel = (_ref3 = options.includeLevel) != null ? _ref3 : true;
      this.level = (_ref4 = options.level) != null ? _ref4 : 4;
    }

    Logger.prototype.error = function(message, params) {
      var level, param, prefix, _i, _len;

      prefix = level = "";
      if (this.includePrefix) {
        prefix = "[" + this.prefixText + "]";
      }
      if (this.includeLevel) {
        level = "[ERROR]";
      }
      if (params) {
        for (_i = 0, _len = params.length; _i < _len; _i++) {
          param = params[_i];
          message = "" + message + "\n\t" + (JSON.stringify(param));
        }
      }
      if (this.level > 0) {
        return this.mapping.error("" + prefix + " " + level + " " + message);
      }
    };

    Logger.prototype.warn = function(message, params) {
      var level, param, prefix, _i, _len;

      prefix = level = "";
      if (this.includePrefix) {
        prefix = "[" + this.prefixText + "]";
      }
      if (this.includeLevel) {
        level = "[ERROR]";
      }
      if (params) {
        for (_i = 0, _len = params.length; _i < _len; _i++) {
          param = params[_i];
          message = "" + message + "\n\t" + (JSON.stringify(param));
        }
      }
      if (this.level > 1) {
        return this.mapping.warn("" + prefix + " " + level + " " + message);
      }
    };

    Logger.prototype.info = function(message, params) {
      var level, param, prefix, _i, _len;

      prefix = level = "";
      if (this.includePrefix) {
        prefix = "[" + this.prefixText + "]";
      }
      if (this.includeLevel) {
        level = "[ERROR]";
      }
      if (params) {
        for (_i = 0, _len = params.length; _i < _len; _i++) {
          param = params[_i];
          message = "" + message + "\n\t" + (JSON.stringify(param));
        }
      }
      if (this.level > 2) {
        return this.mapping.info("" + prefix + " " + level + " " + message);
      }
    };

    Logger.prototype.debug = function(message, params) {
      var level, param, prefix, _i, _len;

      prefix = level = "";
      if (this.includePrefix) {
        prefix = "[" + this.prefixText + "]";
      }
      if (this.includeLevel) {
        level = "[ERROR]";
      }
      if (params) {
        for (_i = 0, _len = params.length; _i < _len; _i++) {
          param = params[_i];
          message = "" + message + "\n\t" + (JSON.stringify(param));
        }
      }
      if (this.level > 3) {
        return this.mapping.debug("" + prefix + " " + level + " " + message);
      }
    };

    Logger.prototype.setLevel = function(level) {
      return this.level = level;
    };

    Logger.prototype.getLevel = function() {
      return this.level;
    };

    return Logger;

  })();

}).call(this);