[anuraaga]

Ignores content-type parameters except for JSON which must be utf-8

connectrpc/connectrpc.com#447
connectrpc/conformance#1191

[stefanvanburen]

Looks good to me; matches connectrpc/connectrpc.com#447 as far as I can tell. A few small things, none blocking:

• validate_response and validate_stream_response parse the content type and then codec_name_from_content_type parses it again; maybe just have one return both?
• The return "" for "JSON with a bad charset" only works because self._codecs.get("") misses and we 415; might be worth a comment (or None) so nobody accidentally registers a codec under "" 😅.
• The new client tests live in test/test_client_shared.py, which otherwise tests _client_shared — not sure if there's a better home for ConnectClientProtocol tests. And test_proto_charset_ignored doesn't seem to have an async twin like its neighbors.

(FWIW, _parse_content_type splits on ; without respecting quotes, so something like foo="a;charset=latin1" would 415. Pretty contrived, and conformance doesn't cover it, so probably fine to leave.)

[anuraaga]

The return "" for "JSON with a bad charset" only works because self._codecs.get("") misses and we 415; might be worth a comment (or None) so nobody accidentally registers a codec under "" 😅.

Don't think that'll happen so leaving it ;)