I created a Web-Socket application in Wicket having a server that pushes messages to all clients. After registrating the clients (application, sessionId and Key (PageId)) the server pushes the messages. So far so good. But if I have multiple browser windows of the same browser on the same client, only one window receives the message and processes it.
Do all browser windows (of the same browser) share the same sessionId? If yes, is there a way to differ between them?
All browsers (from the same vendor, e.g. Firefox) will share the same session id. But if the page id is different then there will be separate web socket registrations and all of them will have their own connection, i.e. all of them will be able to send/receive messages.
If you need to be notified by Wicket when the user opens a second tab/window for the same page id then use org.apache.wicket.ajax.AjaxNewWindowNotifyingBehavior on the page. Most probably you will want to use setResponsePage(page.getClass()) to create a new instance of the same page and have a new WebSocket connection for it.
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I am a bit confused about how one uses websockets. I have already set up a websocket server and are able to receive from server and send to server.
My question is. When using websockets, are you supposed to drop the ajax part completely? Or are you supposed to use websockets alongside ajax?
Example:
I want to use websockets on a chat service on a website where users can log in. When logging in, I use ajax. When on the message page I use websockets to receive future messages, and send future messages. But when navigating to the messages page, I use ajax to get the messages from database.
Is this the correct way of using websockets? Or should I do everything in websockets since 1 user 1 active connection is more efficient? Or should 1 user have 1 websocket connection, but still keep sending ajax requests to the server when navigating to some pages without reloading the site, using ajax?
What is the best practice when creating a large application where users can log in, navigate to pages to load stuff async, but still wanting that bidirectional real time benefits of websockets on stuff like messaging services and notification services on that same website?
There is no reason you cannot use both. I think the solution depends on what server side resources you are using. I may need access to a server through websockets to get updates to a chat dialogue. I may use a completely different system to get user statistics or provide authentication.
I don't think there is a specific answer to your question as it varies depending on the application in question.
I am implementing an Openfire chat client in a web site with Strophe.js. I managed to get multiple sessions and multiple windows reloading page and reconnecting back. Now I have challenge in restoring the chat history.
But the first issue I am stuck at when a user opens two tabs of our site it creates two xmpp sessions with different resource ID's but now say
a#example.com/tab1 sent a message to friend this should be synchronized in tab2
Example if you send chat message from gtalk user sent message will be updated and showin in gmail chat window.
Any one has any idea.
Thanks you very much for the time and help.
The routing logic for multiple resources is up to the server implementation. The GTalk server routes messages sent to bare Jids to all connected resources. Many other servers (also Openfire) send messages to bare Jids to the most available resource, which is the one with the highest priority.
If each of your tabs has its own resource then I suggest to send the messages to each resource (full jid) manual. You get all connected resources of your subscribed contacts with the presence.
Yes, there is. Have a look at XEP-0280: Message Carbons ( http://xmpp.org/extensions/xep-0280.html )
Both your client as well as your server have to support it in order to fully work.
Source : https://superuser.com/questions/866785/is-there-a-way-to-sync-xmpp-messages-across-different-devices-with-standard-xmp
I have an intranet based CRM application developed in CodeIgniter 2.1 where the application is running on a local Apache server and around 20 clients are accessing it over LAN. This is to be connected to a call center setup where the call center application (running on a separate server) will do a HTTP post with caller's number as well as terminal number of the agent where the call is arriving to a URL of my Codeigniter application. I am using this data to populate a database table of call records.
Now from the terminal number (each terminal has static IP, and a session in Codeigniter is linked to IP as well) I can find out which user (login session) of my application is about to receive the call. I want to find a way out how I can send data from server side (it will be regarding the call like the number who is calling, past call records etc.) to that specific user's browser via AJAX or something similar? The agent's browser needs to display this information sent from server.
Periodic polling from browser by jquery etc. is not possible as the data needs to be updated almost instantaneously and rapid polling up to this extent will lead to high CPU usage at client end as well as extra load on network.
P.S.: I only want to know how to modify the browser data from server end.
In AJAX, asynchronous request/response doesn't involve polling; there's just an open TCP connection and non-blocking I/O. The client makes a request but returns immediately; when the server sends the response, the client is notified. So you can achieve what you want with AJAX's XMLHttpRequest without polling[1]. All you need is a url from which to serve your notifications. You could have one request thread and a general dispatch method, or different urls and different threads for each, depending on how you needed to scale.
[1] Well, to be honest, with very little polling. You'd really need to establish what the session/global timeout was and reissue requests within that time limit.
I'm giving socket.io a whirl and I'm curious as to what I should and shouldn't be doing with websockets.
For example is there a way to authenticate a websocket (include id in every message perhaps?)? Let's say I'm creating a 'google docs' like app in which people can create new documents. Should I be using AJAX to create new documents instead of websockets? That way I can use the standard HTTP transport layer to do all of the user authorization (checking session, etc) and then simply ping back the page with a websocket event. Curious as to how people handle situations like this.
I would recommend using AJAX wherever you do not absolutely need web sockets. Web sockets end up creating more load on the server side (socket.io will take care of fallbacks in case web sockets & flash sockets are not available). In short, use web sockets where you need to maintain that state/connection to the client.
If you wish to use web sockets, using cookies with socket.io would be one approach that would allow you to keep track of your sessions. If not using socket.io right away, you can send req.sessionID (key) to the client, store the session information in Redis/Mongo etc. When the socket.io connection is attempted, read the cookie value & send it to the server - where you can get the session store information. There may be issues if you use flash sockets as one of the fallbacks.
Hope this helps.
Is there a way to open a websocket on one page and then reuse it on another page (within the same tab, after a user clicks on a link, for example) rather than have to open a new websocket after each page load? Is browser storage able to hold onto an open socket?
The aim is to be able to keep to one websocket per user (or tab) and it would be great to do this without needing to move between pages in a non-traditional way, for example loading content into a div using Javascrpt each time the user interacts with the page.
The answer is no.
Even if the socket is not explicitly closed by calling mySocket.close();, the socket will be closed by the browser on reload.
I tried storing the Web Socket object in local storage and using it to retrieve data again. The object returned is valid, but the connection in not there anymore. Because, when the page reloads, the socket is ungracefully terminated.
Message at server side says:
[Errno 10053] An established connection was aborted by the software in your host machine
There you go...
A different approach would be to keep the user instead of the socket across different pages. By that i mean you store the client's ID in a cookie with javascript, each time the user try to open a new socket from any of your website pages, you send this ID to the server and then the server have a way to know that this new connection is from the same user.
I've done that in a recent project and it work perfectly :) Depending on what you are planning to do, you can keep the state of the user on your server with his ID, or store it in an other cookie, or event use flash to store it in a shared object !
Shared Web Workers would allow you to share a WebSocket connections for multiple tabs that are loaded from the same origin/site.
Shared Web Workers are only currently supported on Chrome, Safari, Opera.