B4J Question Websocket Connect

[lip]

I have hundreds of Raspberry Pi's connecting to a central Rapsberry Pi server, all running B4J.

The server is based on the Server Example code but with much modification.

On the server, I am getting multiple WebSocket_Connected events called from the same session. This is not happening all the time but at least one-in-ten connection attempts do this:-

Private Sub WebSocket_Connected (WebSocket1 As WebSocket)
ws = WebSocket1
LogWithTime("Session (" & ws.Session.Id & ") Connected")
end sub

Logs
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected
12:21:30 Session (node0xnk84gn8nnftx8zwroxs16467105) Connected

Once connected, the devices run a function IdentifyOnServer command so that the websocket instance on the server can be identified by a unique identifier, however, I am getting hundreds of websocket sessions which never get the IdentifyOnServer command, presumably as the connection gets replaced by a duplicated connection. I don't seem to be able to destroy these instances in the Server. I have tried ws.close and ws.session.invalidate but the unidentified instances seem to remain active.

I would look at the log of the Raspberry pi client concerned, but I cannot identify it from the the SessionID.

Question 1: Is it possible to set an attribute in the client BEFORE I call ws.Connect on the client, so that every every Websocket_Connected event on the server can be associated with a particular client?

Possibly related: I have been putting the Sessions IDs into a map on the server, and I can see that within a minute or two of starting the server I am getting 2000+ unique SessionIDs from 500 Clients.

Question 2: Can each client connect with mutiple SessionsIDs at the same time? Or does this mean that they are losing the connection then reconnecting with a new SessionID? Or is the SessionID created by the Server?

 

[Erel]

The server session works with a cookie. It expects the client to properly keep the cookie and send it when it connects. This is not the case if you are connecting with WebsocketClient.

Why not let the client send some random id and use it instead?

 

[lip]

When the Client Connects, I don't seem to get the option to send any ID:-

Public Sub Connect(Url As String)
ws.Connect(Url)
End Sub

 

[Erel]

Please use [code]code here...[/code] tags when posting code.

1. You can add the id as a URL parameter. Get it on the server with Websocket1.UpgradeRequest.GetParameter.
2. Assuming that you are using WebSocketHandler class, you can raise an event from the client and send any data you like.

 

[lip]

Sounds like a plan. Thanks. I'll give it a try...