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@rwaldron
Created June 7, 2010 20:05
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<?php
header("Content-Type: text/event-stream\n\n");
echo 'data: ' . json_encode(
array(
0 => array(
'time' => time(),
'message' => 'Some kind of foo'
),
1 => array(
'time' => time(),
'message' => 'Some kind of quux'
)
)
) . "\n";
?>
<script src="firefox-event-source.js"></script>
<script>
console.log(EventSource);
var eventSource = new EventSource('event.php');
console.group('eventSource')
console.log(eventSource);
console.log(eventSource.constructor);
console.groupEnd();
eventSource.addEventListener('open', function (event) {
console.log('OPEN!');
}, false);
eventSource.addEventListener('message', function (event) {
var message = JSON.parse(event.data);
console.log(message);
}, false);
</script>
;(function (w) {
if ( !w['EventSource'] ) {
// parseUri 1.2.2
// (c) Steven Levithan <stevenlevithan.com>
// MIT License
var parseUri = function(str) {
var o = {
key: ['source','protocol','authority','userInfo','user','password','host','port','relative','path','directory','file','query','anchor'],
q: {
name: 'queryKey',
parser: /(?:^|&)([^&=]*)=?([^&]*)/g
},
parser: {
strict: /^(?:([^:\/?#]+):)?(?:\/\/((?:(([^:@]*)(?::([^:@]*))?)?@)?([^:\/?#]*)(?::(\d*))?))?((((?:[^?#\/]*\/)*)([^?#]*))(?:\?([^#]*))?(?:#(.*))?)/
}
},
m = o.parser.strict.exec(str),
uri = {},
i = 14;
while (i--) uri[o.key[i]] = m[i] || '';
uri[o.q.name] = {};
uri[o.key[12]].replace(o.q.parser, function ($0, $1, $2) {
if ($1) uri[o.q.name][$1] = $2;
});
return uri;
};
// EventSource implementation
function EventSource( resource ) {
var that = (this === window) ? {} : this,
retry = 1000, offset = 0,
boundary = "\n", queue = [], origin = '',
lastEventId = null, xhr = null, source = null, matches = null, resourceLocation = null;
that.toString = function () { return '[object EventSource]' };
// EventSource listener
that.addEventListener = function (type, listener, useCapture) {
document.addEventListener(type, listener, useCapture);
};
// EventSource dispatcher
that.dispatchEvent = function (event) {
document.dispatchEvent(event);
};
resourceLocation = parseUri(resource);
// same origin policy
if ( resource.match(/http/) && resource.match(/http/).length ) {
if ( resourceLocation.host !== location.host ) {
throw DOMException;//"SECURITY_ERR: DOM Exception";
}
}
that.URL = resourceLocation.source;
var openConnectionXHR = function() {
xhr = new XMLHttpRequest();
xhr.open('GET', that.URL, true);
// FIRE OPEN EVENT
var openEvent = document.createEvent('UIEvents');
openEvent.initEvent('open', true, true);
openEvent.origin = document.domain;
openEvent.source = null;
that.dispatchEvent(openEvent);
if ( lastEventId ) {
xhr.setRequestHeader('Last-Event-ID', lastEventId);
}
xhr.onreadystatechange = function() {
switch (xhr.readyState) {
case 4: // disconnect case
pseudoDispatchEvent();
reOpenConnectionXHR();
break;
case 3: // new data
processMessageFromXHR();
break;
}
}
xhr.send(null);
}
var reOpenConnectionXHR = function() {
xhr = null;
offset = 0;
setTimeout(openConnectionXHR, 1000);
}
var processMessageFromXHR = function() {
var stream = xhr.responseText.split(boundary);
// Abandon if empty
if ( stream.length < offset ) {
return;
}
for ( var i = 0; i < stream.length; i++ ) {
queue.push(stream[i]);
}
pseudoDispatchEvent();
}
var pseudoDispatchEvent = function() {
var data = '', name = 'message';
queue.reverse();
while (queue.length > 0) {
line = queue.pop();
var dataIndex = line.indexOf(':'), field = null, value = '';
if (dataIndex == -1) {
field = line;
value = '';
}
else if (dataIndex == 0) {
// Ignore Comment lines
continue;
}
else {
field = line.slice(0, dataIndex)
value = line.slice(dataIndex+1)
}
if (field == 'event') {
name = value;
}
if (field == 'id') {
lastEventId = value;
}
if (field == 'retry') {
value = parseInt(value);
if (!isNaN(value)) {
retry = value;
}
}
if (field == 'data') {
if (data.length > 0) {
data += "\n";
}
data += value;
}
}
var fireEvent = document.createEvent('UIEvents');
// MessageEvent causes "setting a property that has only a getter" Errors
if ( data.length > 0 ) {
fireEvent.initEvent(name, true, true);
fireEvent.lastEventId = lastEventId;
fireEvent.data = data.replace(/^(\s|\u00A0)+|(\s|\u00A0)+$/g, '');
fireEvent.origin = document.domain;
fireEvent.source = null;
that.dispatchEvent(fireEvent);
}
}
// INIT EVENT SOURCE CONNECTION
openConnectionXHR();
};
window['EventSource'] = EventSource;
}
})(window);
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