Redirects to `wss://...` don't work

[SoMuchForSubtlety]

If the server responds with 302 https://test.com/ws the redirect works, but if the response is 302 wss://test.com/ws the redirect fails with failed to WebSocket dial: failed to send handshake request: Get "wss://test.com/ws": unsupported protocol scheme "wss"

I was able to fix the issue by specifying a custom http.Client in the DialOptions

HTTPClient: &http.Client{
	CheckRedirect: func(req *http.Request, via []*http.Request) error {
		switch req.URL.Scheme {
		case "ws":
			req.URL.Scheme = "http"
		case "wss":
			req.URL.Scheme = "https"
		case "http", "https":
		default:
			return fmt.Errorf("unexpected url scheme: %q", req.URL.Scheme)
		}
		return nil
	},
},

Do you think this should be included in the default client? I would be happy to open a PR with the functionality,

[nhooyr]

Hmm interesting. I'm not sure what browsers do here. Do they accept both on redirect? If so, we should too. I was under the impression they only used http and https.

[SoMuchForSubtlety]

From the WebSocket spec¹

Once the client's opening handshake has been sent, the client MUST
wait for a response from the server before sending any further data.
The client MUST validate the server's response as follows:

1. If the status code received from the server is not 101, the
   client handles the response per HTTP [RFC2616] procedures. In
   particular, the client might perform authentication if it
   receives a 401 status code; the server might redirect the client
   using a 3xx status code (but clients are not required to follow
   them), etc. Otherwise, proceed as follows.

Footnotes

1. https://www.rfc-editor.org/rfc/rfc6455 ↩

[nhooyr]

I don't see how that clarifies the issue at hand? It doesn't speak on whether the redirect URL should use http or https.

[nhooyr]

Sorry I mean wss or https.

[nhooyr]

I'll make it work anyway.

[nhooyr]

Done in dev but still needs a test.

[nhooyr]

Done.