grpc-web + envoy does not work

[ritchieanesco]

Proposal

I've setup a client-side app with react which uses connectrpc's transport for grpc-web protocol and sends requests to envoy over HTTP/1.1 and gets proxied to wiremock server.

The wiremock stubs contains "grpc-status-name" : "OK" response header however it seems no headers get added when looking at envoy proxy logs. See excerpt from log:

2024-10-16 08:49:44 [2024-10-15 21:49:44.222][28][debug][http] [source/common/http/conn_manager_impl.cc:1516] [C0][S4239721515345536154] encoding headers via codec (end_stream=false):
2024-10-16 08:49:44 ':status', '200'
2024-10-16 08:49:44 'content-type', 'application/grpc-web+proto'
2024-10-16 08:49:44 'grpc-encoding', 'identity'
2024-10-16 08:49:44 'grpc-accept-encoding', 'gzip'
2024-10-16 08:49:44 'content-encoding', 'gzip'
2024-10-16 08:49:44 'x-envoy-upstream-service-time', '2139'
2024-10-16 08:49:44 'date', 'Tue, 15 Oct 2024 21:49:44 GMT'
2024-10-16 08:49:44 'server', 'envoy'

In addition to this, the response payload does not include the required grpc trailers as evidenced by this log:

2024-10-16 07:14:55 [2024-10-15 20:14:55.595][41][debug][http] [source/common/http/conn_manager_impl.cc:1533] [C0][S5164429598623932382] encoding trailers via codec:

2024-10-16 07:14:55 [2024-10-15 20:14:55.596][41][debug][http2] [source/common/http/http2/codec_impl.cc:1417] [C1] stream 1 closed: 0

The missing data from this response results in the react application throwing a missing trailers error.

wiremock-main.zip

Reproduction steps

Follow README to install and run the attached source code.

See Test mock server integration section to reproduce issue.

References

No response