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Real Time Functionlity with php

I am working on attendance system where project management system is also handling using Javascript\Jquery at client side and PHP\MySQL at server side.
A feature in my web app is user message to admin. For this I have applied an ajax request which is made by setTimeout function (after every 15 seconds) to check that is there any new message comes in database if yes then return it to the admin.
It working fine but the drawback is (as you know) continuous request to server which really poor and bad. As I know that real time functionality can solve this problem I have checked some link websocket.io and signlR but there are applicable with Nodejs and asp.net.
So, how can I apply real time functionality with php or I get that new data have reached in to database without continues request with ajax.

There are actually some PHP tools for doing this now. For instance, check out Ratchet.
It's also possible to do bi-directional sockets by creating a simple TCP/IP server. I've done this before for bi-directional communication between a PHP server and a desktop app.
http://php.net/manual/en/sockets.examples.php

php mysql background process

i have developing a website that user can chat with other user if they are online . if one user send a message will notify that receiver on their screen , these checking process are happen in background process , i have an option of using
setinterval method and javascript self execution method
but i am looking much faster background process methods which will check every seconds if message or notification arrived .
could any one give suggestion for this.

You can use HTML5 websockets.
WebSockets is an advanced technology that makes it possible to open an interactive communication session between the user's browser and a server. With this API(JS functions), you can send messages to a server and receive event-driven responses without having to poll the server for a reply.
below is good link to start
http://www.sanwebe.com/2013/05/chat-using-websocket-php-socket

I think the best match for your needs will be http://elephant.io
Elephant.io provides a socket.io client fully written in PHP that should be usable everywhere in your project.

Take a look at the Thruway Project. It's a PHP websocket implementation using the WAMP protocol, which gives you Publish and Subscribe abilities (you can use that for your chat application) as well as RPC.
A good place to start would to take a look at this chat demo (source code) and then use Thruway as the WAMP router.
I'm one of the developers of the thruway project, so if you run into any issues or have any questions, feel free to ask.

Express web sockets and a central server

I'm creating an app where the server and the clients will run on the same local network. Is it possible to use web sockets, or rather more specifically, socket.io to have one central server and many clients that are running native apps
? The way I understand socket.io to work is that the clients read the web-pages that are served from the server but what happens when your clients become tablet devices running native apps instead of web pages in a browser?
The scenario I'm working with at the minute will have one central server containing a MEAN app and the clients (iPads) will make GET requests to the data available on the server. However, I'd also like there to be real-time functionality so if someone triggers a POST request on their iPad, the server acknowledges it and displays it in the server's client-side. The iPad apps will (ideally) be running native phonegap applications rather than accessing 192.168.1.1:9000 from their browser.
Is this technically possible to connect to the socket server from the native apps or would the devices have to send POST requests to a central server that's constantly listening for new 'messages'? I'm totally new to the whole real-time stuff so I'm just trying to wrap my head around it all.
Apologies if this isn't totally clear, it's a bit hard to describe with just text but I think you get the idea?

Correct me if I am wrong.
You have multiple iPads running native app. They send a POST request to your node JS server which is running in a computer in the same local network. Whenever the server receives a request from app, you want to display that a request has been received in your computer screen.
If my assumptions about the scenario is correct, then it is fairly easy to do. Here are the steps to do it.
Create a small webpage (front end). Load socket IO in the front end page like this -
<script type="text/javascript" src="YOUR_SERVER_IP/socket.io/socket.io.js"></script>
Then connect to server using var socket = io(). This should trigger connection event in your backend.
Handle all POST request from apps normally. Nothing special. Just add a small snippet in between. socket.emit('new_request', request_data). This sends new_request event to front end.
Handle the new_request in your front end using socket.on('new_request', function(request_data) { ... });. That's it. No need to add anything to your native app for realtime update.
The second step would be a little complicated as it is necessary to make socket variable available inside all POST requests. Since you chose node.js, I don't think you need any help with that.

Not totally clear on your project, but I'll try to give you some pointers.
An effective way to send data between native apps and a server is using a REST server. REST is based on HTTP requests and allows you to modify data on the server, which can connect to your database. The data returned is typically either JSON or XML formatted. See here for a brief intro: http://www.infoq.com/articles/rest-introduction
Android/iOS/etc have built in APIs for making HTTP requests. Your native app would send a request to the server, parse the response, and update your native UI accordingly. The same server can be used from a website using jQuery ajax HTTP requests.
Express.js is more suited to serving web pages and includes things like templating. Look into "restify" (see here: mcavage.me/node-restify/) if you just want to have a REST server that handles requests. Both run on top of node.js (nodejs.org).
As far as real-time communication, if you're developing for iOS look into APNS (Apple Push Notification Service). Apple maintains a persistent connection, and by going through their servers you can easily send messages to your app. The equivalent of this on Android is GCM (Google Cloud Messaging).
You can also do sockets directly if that's easier for you. Be careful with maintaining an open socket on a mobile device though, it can be a huge battery drain. Here's a library for connecting ObjC to Socket.IO using websockets, it may be useful for you: https://github.com/pkyeck/socket.IO-objc
Hope that helps!

To answer your question, it is definitely possible. Socket.io would serve as the central server that can essentially emit messages to all of the client. You can also make Socket.io listen for the messages from any of the clients and serve the emitted message to the rest of the clients.
Here's an example of how socket.io can be used. Simply clone, npm install, and run using 'node app.js'

All you have to do is to provide a valid server address when you connect your socket from the iPad clients:
var socket = io.connect( 'http://my.external.nodejs.server' );
Let us know if you need help with actual sending/receiving of socket events.

It is possible to connect to Websockets from your apps.
If you are using PhoneGap then you need a pluging that gives support to websockets in your app (the client) and then use websocket like normal way using Javascript see this.
If your app is native iOS look into this it could help you.

The primary use of the Sockets in your case is to be a bidirectional "pipe" between an app and server. There is no need of server sending the whole web-page to the native app. All what you need is to send some data from server to the client(app) in response to POST (or GET) request and then using this data on client side to update client's UI in real-time. If you are going to use moderate amount of devices (say tens of them), you may have connected all of them to the server permanently keeping individual socket connection open for every individual link server-to-app. Thus you may deliver data and update client's state in real time.
In fact web browsers also employ sockets to communicate to web servers. However as in general case there is no control on amount of concurrent clients in Internet, for the sake of limited networking resources conservation, servers do not keep sockets open for a long time, closing it just after the web-page was sent to client (or timeout has expired). That's how HTTP protocol works on the low level. The server waiting for the HTTP clients (browsers) by listening the 80 port, responding them by sending the whole web page content, then closing the connection and keep waiting for another requests on the same port.
In your case it's basically a good idea to use socket.io as it's a uniform implementation of sockets (ok WebSockets) on both client and server side. The good starting point is here

Delphi server with JavaScript client

Hi I was wondering how one would go about setting up a delphi server that can interact with a javascript client. I am developing a game with this tool : www.scirra.com
It is called construct 2 and it uses javascript. It has a plugin to use socket.io and websockets so either one would be great.
So basicly I want to develop a delphi server that would receive messages from the one javascript client and broadcast it to the other javascript client. If the user wanted to host a game he would run the delphi application and then join the game and wait for other players to join.
To sum up;
(A) Is it possible to use websockets in delphi to communicate with javascript.
(B) if so would someone please make a simple demo.
Thanks for your time

There are some WebSocket client and server implementations available (see WebSocket server implementations for Delphi).
By design, client-side JavaScript (in the browser) can use the WebSocket protocol to communicate with the server. The Delphi WebSocket server implementations then can handle the requests and push data back to the client just like any other WebSocket server library. However, I do not know anything about the code quality or Delphi version compatibility of all these libraries so some additional research is required.
Regarding the Demo: most libraries surely include some demo HTML with JavaScript / WebSocket communication. Simply download it and open it in your favorite text editor ;)
p.s. as I can see socket.io not only supports WebSocket but also long polling so basically you can use any HTTP server library for Delphi to write the server side logic. See:
How can I update HTML pages dynamically with Indy HTTP server using jQuery and "Long Polling"?
How to: update HTML pages dynamically using jQuery and “Long Polling”

Script on server to interact with clients Javascript

I currently have a javascript library that is using a JSON file to print them on the screen in an interactive way. (::We are using D3JS Library)
When we are on a client, we can easily delete, edit and create some nodes, that are updated in the JSON every 5-10 seconds.
The problem comes from two main facts :
First the automatic function that call itself every x seconds could make data corruption if we are doing some stuff on the datas already represented on the screen.
Then the project has been made in order to permit 5 people to interact together. When they are present onto the same session we cannot decently make them refresh every 5 seconds, that cause many overhead and doesn't avoid data corruption.
We have mainly thought about a solution only made with javascript and some AJAX but we realize that it should be reconsidered with a trigger that inform the client that the datas are no longer OK.
We are thinking currently about opening a script onto a server in order to attribute on each client an ID.
The goal would be to detect the modification done on the JSON file (on the server). But the point where we are stuck is :
1) Is there a best scripting language to interact server/web?
2) Which type of things should we use to make the clients update their datas? (socket right?)
About the second point the easiest way would be to call a JS function be we aren't aware of the possibilities given by the shell codes...
Sorry about the fact that we are happy developpers but maybe not enough skilled to solve this problem.
Thanks for your helps !

You can achieve that using pure javascript with the new WebSocket feature.
http://www.html5rocks.com/en/tutorials/websockets/basics/
Edit:
WebSocket is a web technology providing full-duplex communications channels over a single TCP connection. The WebSocket API is being standardized by the W3C, and the WebSocket protocol has been standardized by the IETF as RFC 6455.
WebSocket is designed to be implemented in web browsers and web servers, but it can be used by any client or server application. The WebSocket Protocol is an independent TCP-based protocol. Its only relationship to HTTP is that its handshake is interpreted by HTTP servers as an Upgrade request.[1] The WebSocket protocol makes possible more interaction between a browser and a web site, facilitating live content and the creation of real-time games. This is made possible by providing a standardized way for the server to send content to the browser without being solicited by the client, and allowing for messages to be passed back and forth while keeping the connection open.