Skip to content
Permalink
Branch: master
Find file Copy path
187 lines (159 sloc) 5.5 KB
;(function (global) {
if ("EventSource" in global) return;
var reTrim = /^(\s|\u00A0)+|(\s|\u00A0)+$/g;
var EventSource = function (url) {
var eventsource = this,
interval = 500, // polling interval
lastEventId = null,
cache = '';
if (!url || typeof url != 'string') {
throw new SyntaxError('Not enough arguments');
}
this.URL = url;
this.readyState = this.CONNECTING;
this._pollTimer = null;
this._xhr = null;
function pollAgain(interval) {
eventsource._pollTimer = setTimeout(function () {
poll.call(eventsource);
}, interval);
}
function poll() {
try { // force hiding of the error message... insane?
if (eventsource.readyState == eventsource.CLOSED) return;
// NOTE: IE7 and upwards support
var xhr = new XMLHttpRequest();
xhr.open('GET', eventsource.URL, true);
xhr.setRequestHeader('Accept', 'text/event-stream');
xhr.setRequestHeader('Cache-Control', 'no-cache');
// we must make use of this on the server side if we're working with Android - because they don't trigger
// readychange until the server connection is closed
xhr.setRequestHeader('X-Requested-With', 'XMLHttpRequest');
if (lastEventId != null) xhr.setRequestHeader('Last-Event-ID', lastEventId);
cache = '';
xhr.timeout = 50000;
xhr.onreadystatechange = function () {
if (this.readyState == 3 || (this.readyState == 4 && this.status == 200)) {
// on success
if (eventsource.readyState == eventsource.CONNECTING) {
eventsource.readyState = eventsource.OPEN;
eventsource.dispatchEvent('open', { type: 'open' });
}
var responseText = '';
try {
responseText = this.responseText || '';
} catch (e) {}
// process this.responseText
var parts = responseText.substr(cache.length).split("\n"),
eventType = 'message',
data = [],
i = 0,
line = '';
cache = responseText;
// TODO handle 'event' (for buffer name), retry
for (; i < parts.length; i++) {
line = parts[i].replace(reTrim, '');
if (line.indexOf('event') == 0) {
eventType = line.replace(/event:?\s*/, '');
} else if (line.indexOf('retry') == 0) {
var retry = parseInt(line.replace(/retry:?\s*/, ''));
if(!isNaN(retry)) { interval = retry; }
} else if (line.indexOf('data') == 0) {
data.push(line.replace(/data:?\s*/, ''));
} else if (line.indexOf('id:') == 0) {
lastEventId = line.replace(/id:?\s*/, '');
} else if (line.indexOf('id') == 0) { // this resets the id
lastEventId = null;
} else if (line == '') {
if (data.length) {
var event = new MessageEvent(data.join('\n'), eventsource.url, lastEventId);
eventsource.dispatchEvent(eventType, event);
data = [];
eventType = 'message';
}
}
}
if (this.readyState == 4) pollAgain(interval);
// don't need to poll again, because we're long-loading
} else if (eventsource.readyState !== eventsource.CLOSED) {
if (this.readyState == 4) { // and some other status
// dispatch error
eventsource.readyState = eventsource.CONNECTING;
eventsource.dispatchEvent('error', { type: 'error' });
pollAgain(interval);
} else if (this.readyState == 0) { // likely aborted
pollAgain(interval);
} else {
}
}
};
xhr.send();
setTimeout(function () {
if (true || xhr.readyState == 3) xhr.abort();
}, xhr.timeout);
eventsource._xhr = xhr;
} catch (e) { // in an attempt to silence the errors
eventsource.dispatchEvent('error', { type: 'error', data: e.message }); // ???
}
};
poll(); // init now
};
EventSource.prototype = {
close: function () {
// closes the connection - disabling the polling
this.readyState = this.CLOSED;
clearInterval(this._pollTimer);
this._xhr.abort();
},
CONNECTING: 0,
OPEN: 1,
CLOSED: 2,
dispatchEvent: function (type, event) {
var handlers = this['_' + type + 'Handlers'];
if (handlers) {
for (var i = 0; i < handlers.length; i++) {
handlers[i].call(this, event);
}
}
if (this['on' + type]) {
this['on' + type].call(this, event);
}
},
addEventListener: function (type, handler) {
if (!this['_' + type + 'Handlers']) {
this['_' + type + 'Handlers'] = [];
}
this['_' + type + 'Handlers'].push(handler);
},
removeEventListener: function (type, handler) {
var handlers = this['_' + type + 'Handlers'];
if (!handlers) {
return;
}
for (var i = handlers.length - 1; i >= 0; --i) {
if (handlers[i] === handler) {
handlers.splice(i, 1);
break;
}
}
},
onerror: null,
onmessage: null,
onopen: null,
readyState: 0,
URL: ''
};
var MessageEvent = function (data, origin, lastEventId) {
this.data = data;
this.origin = origin;
this.lastEventId = lastEventId || '';
};
MessageEvent.prototype = {
data: null,
type: 'message',
lastEventId: '',
origin: ''
};
if ('module' in global) module.exports = EventSource;
global.EventSource = EventSource;
})(this);
You can’t perform that action at this time.
You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window. Reload to refresh your session.