Hi I am trying to make an AJAX instant messenger. I currently have a website (with user logon, admin area etc.) using PHP, MySql, Java Script etc and an AJAX chat prog with 2 chat rooms (and users in room list etc) and it works really good, but dont really know where to go from here (instant messenger wise). I have done some researh which has suggested using an AJAX listener for new messages but I cant find much information on it...or if indeed this is needed or i should use something else. If anyone has any advice where I should go next it would be very, very much appreciated, thanks :)
For a chat or chat-like application which needs realtime and immediate responses probably node.js is a way to go. The mentioned socket.io is also built on node.js. It can be used both on server and client side.
There are lot of blogs/tutorials about node.js. Or you may like this, even if it is for a little fee.
I'd suggest taking a look at www.socket.io for the real-time stuff.
There's even an instant messenger example on the site IIRC.
Why dont you go with something like AJAX Chat, it's free and open source!
I think it might get you going!
Use Stream Hub. Reverse AJAX - pretty cool stuff
You can try cometd of Dojo Foundation!
http://cometd.org/
Node.js
Like a lot of people mentioned I would use node.js/socket.io for this instead of PHP. It has been created to tackle such sort of problems.
Redis
But if you really want to create somethink like this in PHP I would do it using redis(needs to be installed). It has blocking list operations which really help you create something like this. When some user sents a message to another user we push the message to corresponding blocking list of that user. The user listens to an unique blocking list(key) to receive messages.
Can not install Redis
Then you have to use MySQL insert into a table and poll table frequently, but not to much to kill your server/database.
Related
Currently I'm making a chat application where only admin and users chat, no user-to-user chat . The design is: every chat is stored in database and each 2 seconds user and admin make an AJAX request (to a php file) to see if there is a new chat dialogue, and if there is, pull the data into the textbox. It all seems normal and working good.
Problem is as more user is talking to admin at the same time the AJAX request is becoming a lot, and by testing, the web performance already decreased with only 5 users chatting at the same time. And the input is slow too, every time user press enter they got to enter the data into database first before the admin can read it (and vice versa).
I have been told that using JSON is a recommended way, but I have no idea how to do it, can someone please at least tell me how's the design or flow is going to be if use JSON? Or is there a better way to make it? (by the way, using node.js is currently impossible for my current hosting, so don't put it in suggestion lists, sucks I know).
You should change the AJAX responder phps output to JSON. (you can use the json_encode php function for example.) And you should parse(eval) this in javascript.
I am a bit sceptic. It think It could reduce the network usage by more than 50%.
Maybe you can try a message queue, like 0mq or rabbitmq.
There are a lot of chat examples around.
I am a PHP developer and the title basically says it all. However I was hoping on some more in-depth information as I am starting to get confused about how the flow for the project I work on should go.
For an (web) application I need to implement a feature like Facebook does it with notifying users about replies/comments and instantly showing these.
I figured I could use long-polling with ajax requests but this does not seem to be a nice solution as the notifications never really are instant and it is resource heavy.
So I should use some form of sockets if I understand correctly, and Node.Js would be a good choice. So based on the last assumption I now get confused about the work flow.
I thought about two possible solutions:
1) It seems to me, that if I would use Node.Js I could skip using PHP at all and base the application on Node.js only.
2) Or I could use PHP as a base and only use Node.js for notifying users and instantly showing messages but saving the data using PHP and Mysql.
These two possibilities confuse me and I can't make up my mind about what would be the "best" and cleanest way.
I do not have much experience in Node.js, played with it for a while. But managing and saving data seems to be hard in Node.js so that is why I came up with option 2.
I know Facebook is build on PHP so I am assuming that they save the data via PHP and notify / instantly show replies and comments via Node.
Could someone help me out on this?
Thanks in advance!
EDIT:
I just noticed, Stackoverflow does something similar. I get a notification in the upper left, and below my question a box with "new answer to this question". I am really interested in the technologie(s) used.
Well you could use node.js for the notifications and PHP for your app.
By googling I found this about real-time-notifications.
You could also just use node.js with socket.io, but this means that you have to learn new technologies as you mention that you have no experience with node.
I haven't used it but you could check this project, for websockets in PHP.
When you have an update that you want to notify users you can use the publish subscriber pattern to notify the intrested in this update.
Take a look in Gearman too.
Personally, I've built a notification system using the pubsub mechanism of redis, with node.js+socket.io. Everytime that there is an update on a record then there is a publish on the appropriate channel. If the channel has listeners then they will be notified. I also store the last 20 notifications in a Redis list.
The appplication is built in PHP. The notification system is built in node.js. They are different applications that see the same data. The communication occurs via redis. For example in the Facebook context:
1) A user updates his status.
2) PHP stores this to the database and Redis
3) Redis knows that this update must publish to the status channel of the specific user and it does.
4) All the friends of the specific user are listening to his status channel (here comes node.js)
5) Node.js pushes the notification in the browser with socket.io
As for facebook, I have read in an article that is using long polling for supporting older browsers. Not sure for this though, needs citation...
AFAIK It would be via two simple methods :
First one that could be very simple is adding a Boolean column to each record that determines if it has been notified or not.
The second method is creating a table to insert all notifications.
However, I'm not sure if there are alternative methods for better performance, But first method is what I do commonly myself. But I think Facebook is using 2nd method, because it has to notify each one to a lot of users.
Your question maybe dublicate of:
Facebook like notifications tracking (DB Design)
Database design to store notifications to users
You could use Server Side Events it involves a bit of JavaScript but nothing overly complicated I think.
The main bulk of this method is PHP though, so you would just use the PHP to query your DB for notifications and SSE will push them to the user.
It does have some limitations though, most notably it's not supported by IE (huge surprise) thought i'd mention it anyway to let you know of other possibilities.
Hope this helps
I'm tried to implementing a live notification which is like the facebook newsticker and the notifications(on top). I was wondering what's the good solution to archieve this. I implemented an chat application before which I fired AJAX GET request in certain time to archieve the realtime, but it seems not good. I checked facebook using firebug, there is no GET request fired(or it is hided?)
Now here is my scenarion:
In main.php
I have a live ticker and a notifications button.
In bulletion.php and User.php
When I perform an add user,it will go heading to the bulletin or user.php.
How can I get informed in main.php when bulletin.php,user.php successfully created in database?
I checked this question as well before I asked.
notification system in PHP/jQuery
Realtime and php?
I was wonder,what's is long poling Ajax and session-based notification.How it can be archieved? I know Node.js can be good in implementing realtime, can it combine with PHP? and memcached ?
Any can provide sources to refer or example might be good.Thank you.
As a side note, PHP isn't really the best language to use when it comes to push notifications, it's really built around typical get/response kinda flows.
I use PHP for all my page stuff, but when it comes to push notifications of any sort I really like http://www.nodejs.org/ and http://socket.io/ to go with it. They're very easy to get setup, and will play well with you using php for the majority of your work, then using node to deal with push notification kinda stuff.
Have you thought about using HTML5 WebSockets? Have a look at EventSockets and the kickstart project on Github.
I've had much success with the server-sent events standard. It's very simple and works perfectly but it's only supported in modern browsers.
Meteor is a comet server using PHP and JavaScript to push data to browsers. It's very slick and worth a look, although it may be a little hard to setup/implement.
Edit: Quick demo here
I'd like to create an application where when a Super user clicks a link the users should get a notification or rather a content like a pdf for them to access on the screen.
Use Case: When a teacher wants to share a PDF with his students he should be able to notify his students about the pdf available for download and a link has to be provided to do the same.
There are several ways you can accomplish this. The most supported way is through a technique called Comet or long-polling. Basically, the client sends a request to the server and the server doesn't send a response until some event happens. This gives the illusion that the server is pushing to the client.
There are other methods and technologies that actually allow pushing to the client instead of just simulating it (i.e. Web Sockets), but many browsers don't support them.
As you want to implement this in CakePHP (so I assume it's a web-based application), the user will have to have an 'active' page open in order to receive the push messages.
It's worth looking at the first two answers to this, but also just think about how other sites might achieve this. Sites like Facebook, BBC, Stackoverflow all use techniques to keep pages up to date.
I suspect Facebook just uses some AJAX that runs in a loop/timer to periodically pull updates in a way that would make it look like push. If the update request is often enough (short time period), it'll almost look realtime. If it's a long time period it'll look like a pull. Finding the right balance between up-to-dateness and browser/processor/network thrashing is the key.
The actual request shouldn't thrash the system, but the reply in some applications may be much bigger. In your case, the data in each direction is tiny, so you could make the request loop quite short.
Experiment!
Standard HTTP protocol doesn't allow push from server to client. You can emulate this by using for example AJAX requests with small interval.
Have a look at php-amqplib and RabbitMQ. Together they can help you implement AMQP (Advanced Message Queuing Protocol). Essentially your web page can be made to update by pushing a message to it.
[EDIT] I recently came across Pusher which I have implemented for a project. It is a HTML5 WebSocket powered realtime messaging service. It works really well and has a free bottom tier plan. It's also extremely simple to implement.
Check out node.js in combination with socket.io and express. Great starting point here
I've written a php file that changes a MySql table entry when it receives an http post. I would also like the php file to send out a notification to the table entry's owner. This idea is similar to a chat room or instant messengering program. I've looked at php chat scripts but I really need something that has a very simple interface that is customizable. Can anyone point me in the right direction?
So you want to synchronize a set of clients, do you?
If so, look at the Long Polling technique. It's quite simple: The client opens a connection but the server does not respond until data is updated.
On the downside this won't work well with PHP. You will need to sleep() several connections, therefore blocking PHP processes.
If you have the possibility I would recommend using node.js to do stuff like that. Long Polling Chats are quire simple to implement using node ;)
I would use a named look for event triggerning and a jabber bot (extensions exist for several languages).
http://www.xaprb.com/blog/2007/08/29/how-to-notify-event-listeners-in-mysql/