Logger javascript

Exemple d'utilisation:

 var logger = new Logger();
 logger.setLevelWriter(Logger.ERROR_LEVEL, new AlertWriter());
 logger.setLevelWriter(Logger.NOTICE_LEVEL, new ConsoleWriter());
 logger.error("une erreur");
 logger.notice("un message");

Va afficher une boite d'alerte indiquant "Une erreur" et la stack d'appel puis "un message" (avec la stack d'appel toujours) dans la console Javascript.

Il est possible de n'afficher que les messages contenant un certain texte en utilisant : logger.setLevelFilter(Logger.ERROR_LEVEL, "TEST");

1. --

Le code :

 // constructor
 Logger = function ()
 {
	var writer = null; // use this to default to some writer
	this._writers = new Array(writer, writer, writer, writer);
	this._filters = new Array(null, null, null, null);
 };

 // static fields

 //IDL: const long DEBUG_LEVEL = 0
 Logger.DEBUG_LEVEL = 0;
 //IDL: const long NOTICE_LEVEL = 1
 Logger.NOTICE_LEVEL = 1;
 //IDL: const long WARNING_LEVEL = 2
  Logger.WARNING_LEVEL = 2;
 //IDL: const long ERROR_LEVEL = 3
 Logger.ERROR_LEVEL = 3;
 //IDL: const long ALL_LEVELS = -1
 //Use this constant for setting all levels at once
 Logger.ALL_LEVELS = -1; //

 // instance methods
 //IDL: ILogWriter getLevelWriter(in long level)
 //Get writer for given level. Can be null if no writer.
 Logger.prototype.getLevelWriter = function (level)
 {
 	if (level < 0 || level > Logger.ERROR_LEVEL)
 		throw "level < 0 || level > Logger.ERROR_LEVEL";

 	return this._writers[level];
 };

 //IDL: void setLevelWriter(in long level, in ILogWriter writer)
 //Set writer for given level. Use writer=null for no writer.
 Logger.prototype.setLevelWriter = function (level, writer)
 {
 	if (level != Logger.ALL_LEVELS && level > Logger.ERROR_LEVEL)
 		throw "level != Logger.ALL_LEVELS && level > Logger.ERROR_LEVEL";

 	if (level != Logger.ALL_LEVELS) {
 		this._writers[level] = writer;
 	} else {
 		this._writers[Logger.DEBUG_LEVEL] = writer;
 		this._writers[Logger.NOTICE_LEVEL] = writer;
 		this._writers[Logger.WARNING_LEVEL] = writer;
 		this._writers[Logger.ERROR_LEVEL] = writer;
 	}
 };

 //IDL: string getLevelFilter(in long level)
 Logger.prototype.getLevelFilter = function (level)
 {
 	if (level < 0 || level > Logger.ERROR_LEVEL)
 		throw "level < 0 || level > Logger.ERROR_LEVEL";

 	return this._filters[level];
 };

 //IDL: void setLevelFilter(in long level, in string filter)
 Logger.prototype.setLevelFilter = function (level, filter)
 {
 	if (level != Logger.ALL_LEVELS && level > Logger.ERROR_LEVEL)
 		throw "level != Logger.ALL_LEVELS && level > Logger.ERROR_LEVEL";

 	if (level != Logger.ALL_LEVELS) {
 		this._filters[level] = filter;
 	} else {
 		this._filters[Logger.DEBUG_LEVEL] = filter;
 		this._filters[Logger.NOTICE_LEVEL] = filter;
 		this._filters[Logger.WARNING_LEVEL] = filter;
 		this._filters[Logger.ERROR_LEVEL] = filter;
 	}
 };

 //IDL: void debug(in string msg)
 Logger.prototype.debug = function (msg)
 {
	this._log(Logger.DEBUG_LEVEL, msg);
 };

 //IDL: void notice(in string msg)
 Logger.prototype.notice = function (msg)
 {
	this._log(Logger.NOTICE_LEVEL, msg);
 };

 //IDL: void warning(in string msg)
 Logger.prototype.warning = function (msg)
 {
	this._log(Logger.WARNING_LEVEL, msg);
 };

 //IDL: void error(in string msg)
 Logger.prototype.error = function (msg)
 {
	this._log(Logger.ERROR_LEVEL, msg);
 };

 Logger.prototype._log = function (level, msg)
 {
	if (null === msg || 'string' !== typeof(msg)) return;
	if (null !== this._writers[level]) {
		if (null === this._filters[level] || -1 != msg.indexOf(this._filters[level])) {
			this._writers[level].write(this._formatLog(msg, level));
		}
	}
 };

 Logger.prototype._formatLog = function (msg, level)
 {
	var dateString = new Date();
	var callStack = (level >= Logger.DEBUG_LEVEL) ? this._formatCallStack(null) : '';
	if ('undefined' !== typeof(msg.stack))
		callStack = '(EXCEPTION) ' + this._formatCallStack(msg.stack);
	return '====' + this._levelNum2Text(level) + '====\n' + dateString + '\n' + msg + '\n\nStack:\n' + callStack;
 };

 Logger.prototype._levelNum2Text = function (level)
 {
	var level_txt = null;
	switch (level)
	{
		case Logger.DEBUG_LEVEL:
			level_txt = 'DEBUG';
			break;
		case Logger.NOTICE_LEVEL:
			level_txt = 'NOTICE';
			break;
		case Logger.WARNING_LEVEL:
			level_txt = 'WARNING';
			break;
		case Logger.ERROR_LEVEL:
			level_txt = 'ERROR';
			break;
		case Logger.ALL_LEVELS:
			level_txt = 'ALL LEVELS';
			break;
		default :
			level_txt = 'UNKNOWN LEVEL [' + level + '] Vs [' + this.DEBUG_LEVEL + ']';
			break;
	}
	return level_txt;
 };

 Logger.prototype._formatCallStack = function (s)
 {
	var stack = (null === s) ? Components.stack : s;
	var buf = '';
	var depth = 0;
	while (null !== stack) {
		for (var i = 0; i < depth; i++) buf += ' ';
		if (depth > 3) buf += stack.toString() + '\n';
		depth++;
		stack = stack.caller;
	}
	return buf;
 };

 /* constructor */
 AlertWriter = function ()
 {
	this._buffer = new Array();
	this.autoFlush = true;
	this.bufferSize = 5;
 };

 /* instance methods */
 AlertWriter.prototype.write = function (msg)
 {
	this._buffer.push(msg);
	if (this.autoFlush || this._buffer.length > this.bufferSize) {
		this.flush();
	}
 };

 AlertWriter.prototype.flush = function ()
 {
	for (var i = 0; i < this._buffer.length; i++) {
	     Components.classes['@mozilla.org/embedcomp/prompt-service;1']
                 .getService(Components.interfaces.nsIPromptService)
                 .alert(null, "Logger", this._buffer[i]);
	}
	this._buffer = new Array();
 };

 /* constructor */
 ConsoleWriter = function ()
 {
	this._buffer = new Array();
	this.autoFlush = true;
	this.bufferSize = 5;
 };

 /* instance methods */
 ConsoleWriter.prototype.write = function (msg)
 {
	this._buffer.push(msg);
	if (this.autoFlush || this._buffer.length > this.bufferSize)
		this.flush();
 };

 ConsoleWriter.prototype.flush = function ()
 {
	for (var i = 0; i < this._buffer.length; i++) {
	    Components.classes["@mozilla.org/consoleservice;1"]
               .getService(Components.interfaces.nsIConsoleService)
               .logStringMessage(this._buffer[i]);
	}
	this._buffer = new Array();
 };

 /* constructor */
 ConsoleAlertWriter = function ()
 {
	this._buffer = new Array();
	this.autoFlush = true;
	this.bufferSize = 5;
 };

 /* instance methods */
 ConsoleAlertWriter.prototype.write = function (msg)
 {
	this._buffer.push(msg);
	if (this.autoFlush || this._buffer.length > this.bufferSize)
		this.flush();
 };

 ConsoleAlertWriter.prototype.flush = function ()
 {
	for (var i = 0; i < this._buffer.length; i++) {
            Components.classes["@mozilla.org/consoleservice;1"]
                .getService(Components.interfaces.nsIConsoleService)
                .logStringMessage(this._buffer[i]);
            Components.classes['@mozilla.org/embedcomp/prompt-service;1']
                .getService(Components.interfaces.nsIPromptService)
                .alert(null, "Logger", this._buffer[i]);
	}
	this._buffer = new Array();
 };

 /* constructor */
 DumpWriter = function ()
 {
	this._buffer = new Array();
	this.autoFlush = true;
	this.bufferSize = 5;
 };

 /* instance methods */
 DumpWriter.prototype.write = function (msg)
 {
	this._buffer.push(msg);
	if (this.autoFlush || this._buffer.length > this.bufferSize)
		this.flush();
 };

 DumpWriter.prototype.flush = function ()
 {
	for (var i = 0; i < this._buffer.length; i++) {
		dump(this._buffer[i]);
		dump("\n");
	}
	this._buffer = new Array();
 };

 /* constructor */
 FileWriter = function ()
 {
	/*IDL: readonly attribute string fileName;*/
	this.fileName = null;
	this._fh = null;
	this._buffer = new Array();
	this.autoFlush = true;
	this.bufferSize = 5;
 };

 /* instance methods */

 /*IDL: void init(in string fileName)*/
 FileWriter.prototype.init = function (fileName)
 {
	this.fileName = fileName;
	this._fh = new File();
	this._fh.open(this.fileName);
 };

 FileWriter.prototype.write = function (msg)
 {
	this._buffer.push(msg);
	if (this.autoFlush || this._buffer.length > this.bufferSize) {
		this.flush();
	}
 };

 FileWriter.prototype.flush = function ()
 {
        if (null === this._fh) return;
	for (var i = 0; i < this._buffer.length; i++) {
		this._fh.putContents(this._buffer[i]);
	}
	this._buffer = new Array();
 };