we have a front end of Angular, backend on Node.js, Apache as web server and socket.io install, when a user refreshes the browser (client) the apache gets a GET request with transport=websocket for the session ID which has been closed/disconnected, which is what it should get as the previous session was keep alive and apache will receive it when the connection closes.
The issue is that our node.js socket.io implementation is responding to the request with 200 status, now when the server responds with 101 as the session ID is already disconnected that packet out will essentially be lost in transit.
Should we be responding with 101 at all, or instead invalidate the request with 400?
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I am trying to build a chat web application. When the user sends a new message (HTTP Request) to the server, I want to send WebSocket notification to the receiver of the message (Angular Client). When the user logs in to the app it opens a websocket connection with the server. I would like to ask you if my logic is right or I can do something better. I want to intercept the handshake before it gets established and grab the session id of the websocket and the Session JWT cookie of the user, so I can store them in my database. So when a user sends a message, the backend should lookup database if there is active websocket connection or not. ALthough, I find this solution difficult to build as I am not sure a websocket session ID is enough to rebuild the Websocket session object from the start. Is there any better way to solve this?
Thank you in advance!
I am using easyrtc and socket.io for my metaverse application. The socket.io uses pollings and websocket connection for providing the multiuser experience in my metaverse.
The client sends polling requests to my server for connection.
At times the path at which the client sends request is taken as localhost:3000 which is my client itself. I want it to serve requests to my server that is present at localhost:3333.
Sometimes it sends requests to localhost:3000 and sometimes it sends the requests correctly to localhost:3333.
Can someone help?
I have a Jersey client and server. And I see this behavior:
In client I post a request
In the server I see the request and start to handle it
Then out of a sudden I receive an empty response with status 504 to the client while the server still processes the request
I've set the client properties to have read and connect timeouts much higher than the time I get the empty response
After further analysis - the gateway timeout was due to a Load-Balancer between the client and the server.
Reconfiguring the timeout in the Load-Balancer solved the issue
websocket session is wrapped in a http session and so when the http session timesout the websocket session also times out.
However, when only the first call is a http call which is based on session cookie and the rest of the time it is a direct established connection,
how does the connection ever close in case of a timeout?
Scenario - We have a reverse proxy that manages the validation check on the sessions. This means it intercepts each call and checks for the validity of the session.
In case the cookies have expired, it returns a 401.
Since I have integrated websockets to this system, the initial websocket call goes through this reverse proxy with a valid cookie, upgrades the request to websocket and thereafter
keeps sending messages directly. The reverse proxy is not aware of these direct messages sent over WS.
Now when the http session expires, the other calls being made to the system get a 401. However the WS connection above does not know about it at all and continues to send/receive messages.
In case of a logout, an invalidate is called on the http session and so all the bound objects are notified and I get a SessionDisconnectEvent. However in case of timeouts I have no indication at all.
How should I terminate the WS connection in such cases?
Stack - spring + sockJS + basic stomp
My observations are that all the websocket sessions that are bound to the http session are not terminated in case of logout. Only the one that initiated the logout gets the SessionDisconnectMessage.
In case of timeouts, there are no indications at all.
To handle timeouts, I make a call to the server soon after I get a message at the client side and look for a 401 on this call. If it returns a 401, I initiate a session close on the client side.
To handle logout, I maintain a map of the http session id and all the websocket sessions associated with it. When I receive a disconnect on any of the websocket sessions, I terminate all the other ws sessions associated with that http session.
I have a webapp, which is running in a browser. That webapp is connected to a server, which uses websockets. So the communication between the server and my client/browser is based on websockets. If some magic event occurs on the server, some webservice sends a new XML / JSON to my webapp and the new data gets displayed.
But how do i, as the client / browser, know if the connection is stil alive? Lets say i do not get any new XML for about 30 seconds. How would i know if the connection is closed/broken/server offline or everything is fine, but on the server himself no new magic event occured.
A websocket connection object has a readyState field which will tell you if the connection is still active (from the dart documentation). The readyState can be either
0 - connection not yet established
1 - conncetion established
2 - in closing handshake
3 - connection closed or could not open
You can also define an event handler for the websocket close event if this is something you'd like to handle (try to reconnect, etc).
3 ways:
rely on TCP to detect loss of connectivity, which will ultimately pop up in JS onclose event
send WebSocket pings from server .. browsers will reply with WS pongs, loss of connectivity is probably more robustly detected also on client side
send app level heartbeats from browser to server, server need to have logic to reply. you can't trigger WS pings from browsers (in JS)