logger.js

'use strict';

var strftime = require('strftime').utc();
var fs = require('fs');
var util = require('util');
require('colors');

module.exports = function (config) {
	config = config || {};
	var exports = {};

	config.levels = config.levels || {
		'trace': 0,
		'debug': 1,
		'log': 2,
		'info': 3,
		'warn': 4,
		'error': 5,
		'fatal': 6
	};

	config.level_abbr = config.level_abbr || {
		'trace': 'trc',
		'debug': 'dbg',
		'log': 'log',
		'info': 'inf',
		'warn': 'WRN',
		'error': 'ERR',
		'fatal': 'FTL'
	};

	config.filename = config.filename || __dirname + '/logs.log';

	config.errorLevel = config.errorLevel || 'log';

	var log_file = fs.createWriteStream(config.filename, { flags: 'a' });

	exports.setLevel = function (errorLevel) {
		config.errorLevel = errorLevel;
	};

	function snipsecret (data) {
		for (var key in data) {
			if (key.search(/secret/i) > -1) {
				data[key] = 'XXXXXXXXXX';
			}
		}
		return data;
	}

	Object.keys(config.levels).forEach(function (name) {
		function log(caption, data) {
			var log = {
				'level': name,
				'message': caption,
				'timestamp': strftime('%F %T', new Date())
			};

			if (data) {
				log.data = snipsecret(data);
			}

			var data_str = util.isObject(log.data) ? JSON.stringify(log.data) : String(log.data);
			var level_str = config.level_abbr[log.level] ? config.level_abbr[log.level] : '???';

			if (config.levels[config.errorLevel] <= config.levels[log.level]) {
				if (log.data) {
					log_file.write(util.format('[%s] %s | %s - %s\n', level_str, log.timestamp, log.message, data_str));
				} else {
					log_file.write(util.format('[%s] %s | %s\n', level_str, log.timestamp, log.message));
				}
			}
			if (config.echo && config.levels[config.echo] <= config.levels[log.level]) {
				try {
					if (log.data) {
						console.log('['+level_str.bgYellow.black+']', log.timestamp.grey, '|', log.message, '-', data_str);
					} else {
						console.log('['+level_str.bgYellow.black+']', log.timestamp.grey, '|', log.message);
					}
				} catch (e){
					console.log(e);
				}
			}
		}

		exports[name] = log;
	});

	return exports;
};