I am creating a web app that requires a live notification system. How would I set up my server to pull data from a mySQL database and then push it to the browser. I have absolutely NO idea how to do this. If anybody can help, it would be much appreciated! Thank you so much!
EDIT: I should probably be more specific, I am pulling data as in XYZ recently created an account, XZY recently ... Thanks so much!
I'm using Orbited right now, it's great!
If you are doing chat or subscription type stuff use stompservice and orbited.
If you are doing 1 to 1 client mapping use TCPSocket.
I can give you some code examples if you want.
I think you've got almost everything. The callback function you have under success needs an argument which stands for the results from search.php
success: function(res) {
goToByScroll("result");
$('#result').html("<br><br><br><br><br><br><br><br><br><br><div class='center'><img src='img/loader.gif' /></div>").hide().fadeIn(2500, function() {
$('#result').html(res + "<br /><br /> Finished");
});
}
res is everything outputted be search.php. Echo, stuff outside of php tags, etc Anything you'd see if you loaded search.php itself.
I don't know if you wanted 'Finished' to still be there. Take it out if you dont.
i think your problem may be in ajax code since you are using formData object . try append the message variable with it
$('#submit').on('click', function(){
var fd = new FormData(this);
fd.append('file',$('#file')[0].files[0]);
fd.append('message ',$('#message').val());
$.ajax({
method:"POST",
url:"<?php echo site_url('home/send_chat');?>",
data: fd,
cache: false,
contentType: false,
processData: false,
success: function(data){
alert(data);
},
error: function(xhr, status, error) {
alert(xhr.responseText);
}
});
});
A great source for all things Comet is Comet Daily. Unfortunately it's not updated all that often any more but there are some fantastic old articles in there. It's contributed to by guys that have been developing Comet solutions for over 10 years.
Comet seems to get incorrectly bundled as meaning just one particular connection mechanism is used, but it's actually a paradigm for realtime push from server to client. Comet servers can use HTTP Streaming, HTTP Long-Polling, classic polling and WebSockets.
If you are interested in the latest Push Technology then you should take a look at WebSockets which is a standardised approach to not only server to client push, but also bi-directional realtime communication between servers and clients (web browsers and other clients).
Some current trending push technologies are:
If you want to use PHP you could struggle to build an application using realtime Push which will scale above a small number of connections. Have a read through this question on concurrency - How to implement event listening in PHP for more information.
You cannot push data to a browser, but what you can do is set up your webpage to poll your server every few seconds for updates. An example setup would be:
From within your website, have a javascript function that runs on a timer every few seconds (or whatever interval works best for your situation).
Start that timer on page load.
That javascript function invokes an AJAX call to a web service on your web server (more on that in a second).
On the server side you'll need some sort of system that tracks these events and stores them somewhere such as in a database table with a timestamp. So for example when XYZ creates an account, that would be logged in this "event" table in the db.
The web service called by the AJAX call will then run a query on that table and retrieve all entries since the last time it was called. Then just update the webpage with those results.
It's obviously not 100% "live" as there will be a small delay depending on what time interval you set in the JS timer but it's pretty close.