easy-log

A lightweight logging library usable in node/CLI or in a browserjavascript app.

Because sometimes it is easier to re-invent the wheel than to upgrade your axle :-)

Easy-Log is less than 200 lines and requires only path and util, making it ideal for usage in a library that may be used in a node-CLI or in a web application through browserify running in the browser.

You can instantiate a logging function that will thereafter output a formatted log statement with each invocation, including a timestamp.

The log level can be set at any point in time, causing all higher priority logs to be filtered out. The LOGFOLDER can be set to an actual folder for use in node CLI applications or set to null (default) in which case the log statements will be output to console (for use in the browser).

The logger function outputs log statements to a log file and implements transparent log file turnover when the log file size exceeds MAXFILESIZE

Usage

var easylog = require('easylog');
easylog.setLogFolder('/user/home/user1'); // set LOGFOLDER
easylog.setLogLevel('WARN');

var logger1 = easylog.logger('logfile1.log'); // logger1 will log to file logfile1.log in folder LOGFOLDER
var logger2 = easylog.logger(); // default is easy.log


logfn1('ERROR', 'module1', 'this is %s message number %d', 'test', 1); 
 // => 2015-10-06T07:28:18.965 [ERROR] [module1] this is test message number 1
logfn1('INFO', 'module1', 'this is %s message number %d', 'test', 1); 
 // => false

easylog defines the following log levels:

var levels = {
	ERROR: 0,
	WARN: 1,
	INFO: 2,
	DEBUG: 3,
	TRACE: 4,
	ALL: 5
};