Commonly used interface for http & ws breaks connections

[mStirner]

Alle Jahre wieder...

When a interface connection is used for http and alter for https, its break the websocket connection.
"RSV ... frame must be clear". This is due to the "keep-alive" handling in the iface.httpAgent():

backend/components/devices/class.interface.js

Lines 285 to 287 in d17066b

	if (agent.protocol === "http:" && !(headers?.upgrade === "websocket" && headers?.connection === "upgrade")) {
	chunk = chunk.toString().replace(/connection:\s?close\r\n/i, "connection: keep-alive\r\n");
	}

The agent is created, cached, and then the agent from the http request is returned:

backend/components/devices/class.interface.js

Lines 210 to 212 in d17066b

	if (this.cachedAgent) {
	return this.cachedAgent;
	}

There needs to be a way to check the URL for which the connection is used.

---

    iface.on("attached", () => {

        console.log("iface attacehd");
        let agent = iface.httpAgent();
        request(`http://${host}:${port}/socket.io/1/?t=${Date.now()}`, {
            agent
        }, (err, result) => {
            if (err) {

                console.error(err);
                process.exit(1);

            } else {

                let start = null;
                let wsp = result.body.toString().split(":")[0];

                console.log("WS GET", wsp)
                let ws = new WebSocket(`ws://${host}:${port}/socket.io/1/websocket/${wsp}`, {
                    agent
                });

Cause the trouble described above.
Add a option to the agent to unpipe everything from the upstream & re-create a new uncached agent?

[mStirner]

Tip

Workaround: Create 2 interfaces with the same host/port settings.
Use one dedicated for HTTP and one for WebSocket connections.

[mStirner]

Use new interface method .bridge() to create new sockets.
In v4 the iface.httpAgent(),iface.httpsAgent() uses this under the hood and no action/workaround is needed anymore.

See mStirner@fe8c2a9