Reverse Ajax implementation using php
I am looking to implement reverse ajax in my application which is usin开发者_运维技巧g PHP and jquery. I have googled a bit about it and found XAJA but that seems to be a paid application. Is there an open source application available for the same or has someone implemented it?
Some pointers or hints would be very helpful.
Thanks in advance.
I know of two types of reverse AJAX:
1- Polling
2- Pushing
I think polling is rather easier to implement, you just have your javascript make a regular request to the server every time interval, and when the server have some data for it it will respond. Its like a ping and some call it heartbeat, but its the very obvious solution for this problem. However it may easily overload the server.
EDIT Simple polling Example code:
Server-Side:
<?php
//pong.php php isn't my main thing but tried my best!
$obj = new WhatsNew();
$out = "";
if ($obj->getGotNew()){
$types = new array();
foreach ($obj->newStuff() as $type)
{
$new = array('type' => $type);
$types[] = $new;
}
$out = json_encode($types);
}
else{
$out = json_encode(array('nothingNew' => true));
}
Client-Side:
function ping(){
$.ajax(
{
url : "pong.php",
success : function (data){
data = JSON.parse(data),
if (data['nothingNew'])
return;
for(var i in data){
var type = data[i]['type'];
if (type && incomingDataHandlers[type]){
incomingDataHandlers[type]();
}
}
});
}
incomingDataHandlers = {
comments: function () {
$.ajax({
url: "getComments.php",
method: "GET",
data: getNewCommentRequsetData() // pass data to the server;
success : function (data){
//do something with your new comments
}
});
},
message: function (){
$.ajax({
url: "getMessages.php",
method: "GET",
data: getNewMessageRequestData() // pass data to the server;
success : function (data){
//do something with your new messages
}
});
}
}
$(docment).ready(function () {
setInterval(ping, 1000);
})
You are looking for what they call "long poll" - I did a "long poll php" and I got this thread on stack overflow:
How do I implement basic "Long Polling"?
you could websockets in conjuction with "flash" websockets because almost all browser have flash on board(average around 96%? => http://www.statowl.com/flash.php) => https://github.com/gimite/web-socket-js. You could use this together with http://code.google.com/p/phpwebsocket/. Still I am wondering if the performance is going to be any good. If it all possible I would use node.js to do reverse ajax. http://socket.io is a really cool project to do this!
Have you checked APE ?
Its a push based real-time data streaming technology over a single low volume ajax connection. The concept is useful, you may be able to replicate the same thing with your server-side implementation
精彩评论