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/**
* Rough FileAppender implementation for log4javascript 1.4.
*
* Copyright 2013 Tim Down.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
(function() {
function BrowserFileAppender(fileName) {
fileName = fileName || "log4javascript.log";
var appender = this;
// Use HTML5 file API if available
window.requestFileSystem = window.requestFileSystem || window.webkitRequestFileSystem;
if (window.requestFileSystem && window.Blob) {
appender.writeMessageToFile = (function() {
var queuedMessages = [];
var errorHandler = function(err) {
var msg = '';
switch (err.code) {
case FileError.QUOTA_EXCEEDED_ERR:
msg = "QUOTA_EXCEEDED_ERR";
break;
case FileError.NOT_FOUND_ERR:
msg = "NOT_FOUND_ERR";
break;
case FileError.SECURITY_ERR:
msg = "SECURITY_ERR";
break;
case FileError.INVALID_MODIFICATION_ERR:
msg = "INVALID_MODIFICATION_ERR";
break;
case FileError.INVALID_STATE_ERR:
msg = "INVALID_STATE_ERR";
break;
default:
msg = "Unknown Error";
break;
}
if (window.console && window.console.error) {
console.error("An error occurred: " + msg, arguments);
}
};
var appendQueuedMessages;
var writing = false;
window.requestFileSystem(
window.TEMPORARY,
5 * 1024 * 1024,
function(fs) {
if (window.console && window.console.log) {
console.log("File system object initialized!");
}
fs.root.getFile(fileName, {create: true}, function(fileEntry) {
appendQueuedMessages = function() {
writing = true;
fileEntry.createWriter(function(fileWriter) {
fileWriter.seek(fileWriter.length);
var blob = new Blob(queuedMessages, {type: 'text/plain'});
fileWriter.write(blob);
queuedMessages.length = 0;
writing = false;
}, errorHandler);
};
}, errorHandler);
},
errorHandler
);
return function(msg) {
queuedMessages.push(msg);
if (appendQueuedMessages && !writing) {
appendQueuedMessages();
}
};
})();
}
// Next strategy: ActiveX, as used in IE.
else if (typeof window.ActiveXObject != "undefined") {
appender.writeMessageToFile = (function() {
var fso;
var queuedMessages = [];
var timer;
var writeMessageToFile = null;
try {
fso = new ActiveXObject("Scripting.FileSystemObject");
var appendQueuedMessages = function() {
timer = null;
// Try opening existing file and create it first if it does not exist
try {
var file = fso.OpenTextFile(fileName, 8, true);
file.Write( queuedMessages.join("") );
file.close();
queuedMessages.length = 0;
} catch (e) {
// Prevent further attempts to write to this file
appender.writeMessageToFile = null;
}
};
writeMessageToFile = function(msg) {
queuedMessages.push(msg);
if (timer) {
window.clearTimeout(timer);
}
timer = window.setTimeout(appendQueuedMessages, 200);
};
} catch(e) {
}
return writeMessageToFile;
})();
}
}
BrowserFileAppender.prototype = new log4javascript.Appender();
BrowserFileAppender.prototype.layout = new log4javascript.PatternLayout("%d{yyyy-MM-dd HH:mm:ss} %-5p - %m{1}%n");
BrowserFileAppender.prototype.append = function(loggingEvent) {
if (this.writeMessageToFile) {
this.writeMessageToFile( this.getLayout().formatWithException(loggingEvent) );
}
};
BrowserFileAppender.prototype.toString = function() {
return "BrowserFileAppender";
};
log4javascript.BrowserFileAppender = BrowserFileAppender;
})();
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