A simple logging library for Node.js

Installing

$ npm install basic-log

Basic usage

var log = require('basic-log');

log('Hello!');

Output:

2013-01-19 09:01:53.478 Hello!

log takes a single argument, converts it to string, and prints it to console.

Other log levels:

log.d('Hello!');
log.i('Hello!');
log.w('Hello!');
log.e('Hello!');

Output:

2013-01-19 09:03:17.671 [debug] Hello!
2013-01-19 09:03:17.671 [info] Hello!
2013-01-19 09:03:17.671 [warn] Hello!
2013-01-19 09:03:17.671 [error] Hello!

Changing the date format

By default, the date format is YYYY-MM-DD hh:mm:ss:mmm in UTC time.

Change it by setting date:

log.date = function() {
	return new Date().getTime() + ' ';
}

log('Hello!');

Output:

1358586277536 Hello!

Or get rid of the time altogether:

log.date = function() {
	return '';
}

log('Hello!');

Output:

Hello!

Changing the output

By default, messages are written using console.log.

Change it by setting output:

log.output = function(message) {
	console.err(message);
}

log('Hello!'); // prints to stderr

Or make it return a value if you like:

log.output = function(message) {
	return message.toUpperCase();
}

console.log(log('Hello!'));

Output:

HELLO!

Creating new instances

If want to avoid changing the global log, you make create a new instance:

var Log = require('basic-log').Log;
var log = new Log(<custom functions>);

A typical use case would be to create your own log module and use it:

lib/my-log.js:

var Log = require('basic-log').Log;

module.exports = new Log({
	date: function() { return new Date().getTime() + ' '; }
});

my-app.js:

var log = require('./lib/my-log');

log('Hi!');