minilog

Features

• Works in the browser and on the server
• Very simple client (no external dependencies; less than 100 lines); looks like a readable stream/eventemitter
• Backends are writable streams; allow for picking whatever transport/format you want
• Logs are optionally scoped/namespaced to a particular module, like TJ's debug and can be enabled/disabled selectively
• log.error, log.warn, log.info, log.trace

Backends:

• Console, file, engine.io
• Support for counting and timing via #event_hashtags, like Olark's hashmonitor (presentation); this is implemented as a backend

Examples

Namespaces

You can namespace logs:

var log = require('minilog')('worker'),
    config = { foo: 'bar' };

require('minilog').pipe(process.stdout);

log.info('Booting', config);
log.error('FooBar');
log('Hello', 'World');

Output:

worker info Booting {"foo":"bar"}
worker error FooBar
worker Hello World

Writing to file

var fs = require('fs'),
    MiniLog = require('minilog'),
    log = MiniLog('worker');

MiniLog.pipe(fs.createWriteStream('./temp.log'));

log('Booting');
log.error('FooBar');

Output:

worker Booting
worker error FooBar

Filtering logs by namespace or level

Filters can be applied to pipes:

MiniLog
  .pipe(process.stdout)
  .filter(function(name, level) {
    var ns = {'worker': true, 'http': true},
        type = {'warn': true, 'error': true};
    return whitelist[name] && type[level];
  });

Formatting

Formatting can be applied to pipes:

MiniLog
  .pipe(process.stdout)
  .format(function(name, level, args) {
    return (name ? name.toUpperCase() + ' - ' : '')
         + (level ? level.toUpperCase() + ' ' : '')
         + args.join(' ') + '\n';
  });

Counting and timing

TODO not done

log.error('cookie problems #nocookies_for_session'); // use #event for counting
log.info('#connected #boot_time=100'); // use #timing=value for timing

Using it in the browser

TODO - use Glue or onejs.