WebSocket Server Not Responding

[Riales]

Hi Monks,

I am trying to write a basic Websocket server with AnyEvent and Protocol::WebSocket::Handshake::Server. However, when I try to test it, the server does not answer the client's request.

I'm watching the traffic with Wireshark and it's looking like the client sends the request and the server responds with an ACK but the server does not send the response.

Here is the server code:

AnyEvent::Socket::tcp_server(undef, undef,
    sub {
        my ($fh, $host, $port) = @_;

        #die;

        my $handle = AnyEvent->new(fh => $fh);

        my $hs = Protocol::WebSocket::Handshake::Server->new();
        
        my $chunk = $handle->{rbuf};
        $handle->{rbuf} = undef;

        if (!$hs->is_done) {
            $hs->parse($chunk);
            $handle->push_write($hs->to_string);
        }
    },
    sub {
        my ($fh, $host, $port) = @_;

        $self->port($port);
        $port_is_assigned->send();
    },
);

This code is a (hopefully relevant) excerpt from a Moose class. If seeing the entire class would help - just let me know!

What I've noticed is that if I uncomment the #die; line above, the thread the code is running in does not appear to die...so I think what I'm stuck on is that the accept callback never gets called. But the prepare callback gets called no problem.

Also, here's the wireshark traffic:

No.     Time        Source                Destination           Protoc
+ol Info
      1 0.000000    127.0.0.1             127.0.0.1             TCP   
+   44315 > 53196 [SYN] Seq=0 Win=32792 Len=0 MSS=16396 TSV=1875375 TS
+ER=0 WS=6

Frame 1 (74 bytes on wire, 74 bytes captured)
Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00
+_00:00:00 (00:00:00:00:00:00)
Internet Protocol, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0
+.1)
Transmission Control Protocol, Src Port: 44315 (44315), Dst Port: 5319
+6 (53196), Seq: 0, Len: 0

No.     Time        Source                Destination           Protoc
+ol Info
      2 0.000019    127.0.0.1             127.0.0.1             TCP   
+   53196 > 44315 [SYN, ACK] Seq=0 Ack=1 Win=32768 Len=0 MSS=16396 TSV
+=1875375 TSER=1875375 WS=6

Frame 2 (74 bytes on wire, 74 bytes captured)
Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00
+_00:00:00 (00:00:00:00:00:00)
Internet Protocol, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0
+.1)
Transmission Control Protocol, Src Port: 53196 (53196), Dst Port: 4431
+5 (44315), Seq: 0, Ack: 1, Len: 0

No.     Time        Source                Destination           Protoc
+ol Info
      3 0.000033    127.0.0.1             127.0.0.1             TCP   
+   44315 > 53196 [ACK] Seq=1 Ack=1 Win=32832 Len=0 TSV=1875375 TSER=1
+875375

Frame 3 (66 bytes on wire, 66 bytes captured)
Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00
+_00:00:00 (00:00:00:00:00:00)
Internet Protocol, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0
+.1)
Transmission Control Protocol, Src Port: 44315 (44315), Dst Port: 5319
+6 (53196), Seq: 1, Ack: 1, Len: 0

No.     Time        Source                Destination           Protoc
+ol Info
      4 0.000553    127.0.0.1             127.0.0.1             TCP   
+   44315 > 53196 [PSH, ACK] Seq=1 Ack=1 Win=32832 Len=186 TSV=1875375
+ TSER=1875375

Frame 4 (252 bytes on wire, 252 bytes captured)
Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00
+_00:00:00 (00:00:00:00:00:00)
Internet Protocol, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0
+.1)
Transmission Control Protocol, Src Port: 44315 (44315), Dst Port: 5319
+6 (53196), Seq: 1, Ack: 1, Len: 186
Data (186 bytes)

0000  47 45 54 20 2f 20 48 54 54 50 2f 31 2e 31 0d 0a   GET / HTTP/1.1
+..
0010  55 70 67 72 61 64 65 3a 20 57 65 62 53 6f 63 6b   Upgrade: WebSo
+ck
0020  65 74 0d 0a 43 6f 6e 6e 65 63 74 69 6f 6e 3a 20   et..Connection
+: 
0030  55 70 67 72 61 64 65 0d 0a 48 6f 73 74 3a 20 31   Upgrade..Host:
+ 1
0040  32 37 2e 30 2e 30 2e 31 3a 35 33 31 39 36 0d 0a   27.0.0.1:53196
+..
0050  4f 72 69 67 69 6e 3a 20 68 74 74 70 3a 2f 2f 31   Origin: http:/
+/1
0060  32 37 2e 30 2e 30 2e 31 3a 35 33 31 39 36 0d 0a   27.0.0.1:53196
+..
0070  53 65 63 2d 57 65 62 53 6f 63 6b 65 74 2d 4b 65   Sec-WebSocket-
+Ke
0080  79 3a 20 33 45 42 4d 47 79 6e 4e 48 43 35 6a 4f   y: 3EBMGynNHC5
+jO
0090  39 37 74 30 6e 6c 72 35 67 3d 3d 0d 0a 53 65 63   97t0nlr5g==..S
+ec
00a0  2d 57 65 62 53 6f 63 6b 65 74 2d 56 65 72 73 69   -WebSocket-Ver
+si
00b0  6f 6e 3a 20 31 33 0d 0a 0d 0a                     on: 13....

No.     Time        Source                Destination           Protoc
+ol Info
      5 0.000568    127.0.0.1             127.0.0.1             TCP   
+   53196 > 44315 [ACK] Seq=1 Ack=187 Win=32768 Len=0 TSV=1875375 TSER
+=1875375

Frame 5 (66 bytes on wire, 66 bytes captured)
Ethernet II, Src: 00:00:00_00:00:00 (00:00:00:00:00:00), Dst: 00:00:00
+_00:00:00 (00:00:00:00:00:00)
Internet Protocol, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0
+.1)
Transmission Control Protocol, Src Port: 53196 (53196), Dst Port: 4431
+5 (44315), Seq: 1, Ack: 187, Len: 0

[Riales]

For the curious, the problem turned out to be scoping issue. $handle would go out of scope once the server initialized. The fix turned out to just be declaring my $handle; before actually creating it in the on-connect callback for tcp_server.