chronolog

This simple Node.js module provides an easy way to write logging messages prefixed with the current date.

Usage

First, require the module:

var chronolog = require('chronolog');

It can format strings - console.log(chronolog('test message')) will print something like:

[2014-11-03 Mon pm 10:50:58] test message

It can wrap the console object:

var log = chronolog(console);

// These will all be prefixed with the current date
log('default message'); // same as log.log
log.log('log message');
log.info('info message');
log.error('error message');
log.warn('warn message');

// These will not be prefixed with the current date
console.log('this is not prefixed');
log.dir('this is not prefixed either');

It can wrap stream objects:

chronolog(process.stdout);

// Now you can do this to write a message prefixed with the current date:
process.stdout.writeLine('test message');

The default date format is designed to be human-readable yet still sort well. You can change the message or the date format (the date format uses Moment.js formatting placeholders and the message format is passed to util.format):

chronolog('test message', 'HH:mm:ss');
// returns '[22:50:58] test message'

var log = chronolog(console, 'HH:mm:ss');
// returns an object that writes messages with the given format

chronolog('test message', {
    date : 'HH:mm:ss',
    str  : '%s: %s'
});
// returns '22:50:58: test message'