[websocket] Fail to connect with WebsocketServer after zephyr updated to 1.11

[xiaoyu3x]

Description

This is a regression issue, after zephyr updated to 1.11. NodeWebSocketClient cannot connect to WebsocketServer.

Test Code

WebSocketServer.js;
NodeWebSocketClient.js;
WebSocketServer4.js;
NodeWebSocketClient4.js;
test-ws4-server-dhcp.js
test-ws4-client-dhcp.js
test-ws4-server.js
test-ws4-client.js
test-ws6-server.js
test-ws6-client.js

Steps to Reproduction

1. make JS=samples/websockets/WebSocketServer.js ROM=256
2. make dfu
3. set up BLE connection
   echo "connect FF:EE:DD:CC:BB:AA 2" > /sys/kernel/debug/bluetooth/6lowpan_control
ip -6 route add 2001:db8::/64 dev bt0
ip -6 addr add 2001:db8::2 dev bt0
4. Node samples/websockets/NodeWebSocketClient.js

Actual Result

Expected Result

Test Builds

Branch	Commit Id	Target Device	Test Date	Result	Comment
master	3f8eb85	Arduino 101	Apr 11, 2017	Pass
master	3f8eb85	FRDM-K64F	Apr 11, 2017	Pass(IPv4)	IPv6 failed by #1842
master	3f8eb85	Linux	Apr 11, 2017	Pass
master	d5d5540	Arduino 101	Apr 11, 2017	Fail
master	d5d5540	FRDM-K64F	Apr 11, 2017	Fail
master	d5d5540	Linux	Apr 11, 2017	Fail

Additional Information

[grgustaf]

Seems to work for me, on A101 at least. Could you retest?

[qiaojingx]

Verified with commit 2273038 in master. Result is as below:
On my Linux(Ubuntu 16.04): This issue is still reproduced. All websocket server can't be connected with error "Unexpected server response:{}". But it works fine with zjs-0.5.

On another Linux(Ubuntu 16.04): This issue is not reproduced. Websocket server can be connected.
I am not sure whether it is caused by test environment or network connection issue.
So close it for now, and I will create another issue if new problem occurred.

[haoxli]

@grgustaf I investigate that this issue occurs by node ws module required by NodeWebSocketClient.js. There are changes in protocol implementation between v5.0.0 and v5.1.0 of ws/lib/websocket.js:

• websocket.js (5.0.0)

if (!protocols) {
     protocols = [];
} else if (typeof protocols === 'string') {
     protocols = [protocols];
} else if (!Array.isArray(protocols)) {
    options = protocols;
     protocols = [];
}

• websocket.js (5.1.0)

if (Array.isArray(protocols)) {
    protocols = protocols.join(', ');
} else if (typeof protocols === 'object' && protocols !== null) {
    options = protocols;
    protocols = undefined;
}

When we use ws 5.1.0 above, the protocols ["first", "my_ws_protocol", "last"] in NodeWebSocketClient.js will be joined with ', ', websocket server receive the protocols with a white space before each protocol expect the first one:

var wss = new WebSocket.Server({
    port: 8080,
    acceptHandler: function(protos) {
        for (var i = 0; i < protos.length; i++) {
           console.log('protos:' + protos[i])
            if (protos[i] == "my_ws_protocol") {
                return protos[i];
            }
        }
        return false;
    }
});

output:

No protocol match with my_ws_protocol, there is error thrown with 'unexpected server response'.

In Node ws module, the server trim the received protocols to align with client.

if (protocol) {
     protocol = protocol.trim().split(/ *, */);

We are not sure the end-user always install latest ws module, so could you do the same trim for protocols in zjs code? or expose trim() API to handle it in JavaScript code, now there is no such kind of method for String.