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yalm

yalm

npm version Dependency Status Build Status XO code style License

A simple javascript logging module for Node.js and the Browser.

Offers 4 logging levels, adds timestamp, severity and colors (even in browser console if possible). Logs via console.log, console.warn (if available) and console.error.

usage

log.debug('a debug message');
log.info('an info message');
log.warn('a warning message');
log.error('an error message');
 
log.info('array:', [null, 1, 'string', true]);
log.info('buffer:', new Buffer([32, 32]));
log('object:', {"key": "val"});

output of above usage example

Node.js

Node.js sample output

Browser

Browser sample output

options

You can set desired loglevel...

log.setLevel('debug'); // default: 'info'. possible values: 4, 'debug', 3, 'info', 2, 'warn', 1, 'error', 0, 'silent'

... and you can disable printing of timestamps, severity and colors

log.setTimestamp(false);
log.setSeverity(false);
log.setColor(false);

aliases

made for humans...

log('...'); // is an alias of log.info('...');
log.warning('...'); // is an alias of log.warn('...');
log.err('...'); // is an alias of log.error('...');

change styling

if you want another timestamp format overwrite the log.ts function...

log.ts = function () {
    // seconds since epoch
    return '' + Math.floor((new Date()).getTime() / 1000);
};

... if you want to change the severity strings overwrite log.map properties

log.map.debug = 'DEBUG:';
log.map.info = 'INFO:';
log.map.warn = 'WARNING:';
log.map.error = 'ERROR:';

custom log targets

if you want to log in a file or smth you can just overwrite the methods log.stdout, log.stdwrn and log.stderr with your own logging function.

log.stderr = log.stdwrn = log.stdout = function () {
    fs.appendFile('log.txt', Array.prototype.slice.call(arguments).join(' '));
};

license

MIT © Sebastian Raff