Console.Log IMproved - clim

A little Node.js module which improves the behavior of the logging methods of the console object without changing its API. Just drop it in.

http://esa-matti.suuronen.org/blog/2012/09/30/improving-console-dot-log-for-node-dot-js/

Improvements

Improvements affect only log, info, warn and error methods.

• Add timestamp
• Add log level LOG/INFO/WARN/ERROR
• Always log to stderr
• Allow prefixing and inheriting

Installation

npm install clim

Usage

Function Signature

Object newconsole = clim( [String prefix], [Object parent], [Boolean/Object patch parent] )

All parameters are optional.

Just shadow the original console object and use it like always:

var console = require("clim")();
console.log("message");
console.info("message");
console.warn("message");
console.error("message");

Or if you want process wide improved console object you can monkeypatch the original object by passing it and true to clim:

require("clim")(console, true);
console.log("message");

Or if you don't want to use the util.format and just pass the arguments to clim.logWrite, you can use noFormat option to do that:

var console = require("clim")("", {}, {
  noFormat: true,
  patch: false
});

console.log("message")

Prefix Inheriting

Add prefix to your log messages by passing it as the first argument:

var console = require("clim")("myapp");
console.log("message");

Sun Sep 30 2012 16:45:57 GMT+0300 (EEST) INFO myapp message

Inherit prefixes from some other console object by passing it as the second parameter:

var clim = require("clim");

var console = clim("myapp");
console.log("message");

function somefunc(){
  var logger = clim("somefunc", console);
  logger.warn("in function");
}

somefunc();

Sun Sep 30 2012 16:59:12 GMT+0300 (EEST) INFO myapp message
Sun Sep 30 2012 16:59:12 GMT+0300 (EEST) WARNING myapp somefunc in function

Customizing

Change date format by overriding getTime:

clim.getTime = function(){
  return new Date().toString();
};

Change global log target and formatting details by overriding logWrite:

clim.logWrite = function(level, prefixes, msg) {
  // Default implementation writing to stderr
  var line = clim.getTime() + " " + level;
  if (prefixes.length > 0) line += " " + prefixes.join(" ");
  line += " " + msg;
  process.stderr.write(line + "\n");

  // or post it web service, save to database etc...
};

Design Philosophies

• Keep the same api as in the original console object
• Small
• No dependecies
• Tests
• MIT Licensed