GoScrobble/web/node_modules/sockjs-client/lib/transport/sender/xdr.js

104 lines
2.4 KiB
JavaScript

'use strict';
var EventEmitter = require('events').EventEmitter
, inherits = require('inherits')
, eventUtils = require('../../utils/event')
, browser = require('../../utils/browser')
, urlUtils = require('../../utils/url')
;
var debug = function() {};
if (process.env.NODE_ENV !== 'production') {
debug = require('debug')('sockjs-client:sender:xdr');
}
// References:
// http://ajaxian.com/archives/100-line-ajax-wrapper
// http://msdn.microsoft.com/en-us/library/cc288060(v=VS.85).aspx
function XDRObject(method, url, payload) {
debug(method, url);
var self = this;
EventEmitter.call(this);
setTimeout(function() {
self._start(method, url, payload);
}, 0);
}
inherits(XDRObject, EventEmitter);
XDRObject.prototype._start = function(method, url, payload) {
debug('_start');
var self = this;
var xdr = new global.XDomainRequest();
// IE caches even POSTs
url = urlUtils.addQuery(url, 't=' + (+new Date()));
xdr.onerror = function() {
debug('onerror');
self._error();
};
xdr.ontimeout = function() {
debug('ontimeout');
self._error();
};
xdr.onprogress = function() {
debug('progress', xdr.responseText);
self.emit('chunk', 200, xdr.responseText);
};
xdr.onload = function() {
debug('load');
self.emit('finish', 200, xdr.responseText);
self._cleanup(false);
};
this.xdr = xdr;
this.unloadRef = eventUtils.unloadAdd(function() {
self._cleanup(true);
});
try {
// Fails with AccessDenied if port number is bogus
this.xdr.open(method, url);
if (this.timeout) {
this.xdr.timeout = this.timeout;
}
this.xdr.send(payload);
} catch (x) {
this._error();
}
};
XDRObject.prototype._error = function() {
this.emit('finish', 0, '');
this._cleanup(false);
};
XDRObject.prototype._cleanup = function(abort) {
debug('cleanup', abort);
if (!this.xdr) {
return;
}
this.removeAllListeners();
eventUtils.unloadDel(this.unloadRef);
this.xdr.ontimeout = this.xdr.onerror = this.xdr.onprogress = this.xdr.onload = null;
if (abort) {
try {
this.xdr.abort();
} catch (x) {
// intentionally empty
}
}
this.unloadRef = this.xdr = null;
};
XDRObject.prototype.close = function() {
debug('close');
this._cleanup(true);
};
// IE 8/9 if the request target uses the same scheme - #79
XDRObject.enabled = !!(global.XDomainRequest && browser.hasDomain());
module.exports = XDRObject;