Compatibility with native gRPC

[antstorm]

Hey,

I'm building an integration with a YARPC API (using gRPC transport and protobuf encoding). Unfortunately I can't use YARPC generated code since the language I'm using (Ruby) is not supported. I'm trying to connect using plain gRPC-generated definitions, but ran into some issues. I was able to manually set caller, service name and encoding using gRPC metadata, but I can't get past setting the correct procedure name:

GRPC::Unimplemented (12:unrecognized procedure "uber.cadence.api.v1.DomainAPI::ListDomains" for service "cadence-frontend". debug_error_string:{"created":"@1632661596.729831000","description":"Error received from peer ipv6:[::1]:7833","file":"src/core/lib/surface/call.cc","file_line":1070,"grpc_message":"unrecognized procedure "uber.cadence.api.v1.DomainAPI::ListDomains" for service "cadence-frontend"","grpc_status":12})

I tried using the rpc-caller-procedure header, but it seems like it's not taken into account the same way as other headers (such as rpc-caller and rpc-service).

Does anyone know what other manipulations I need to do to the native gRPC request to trick a YARPC server to accept it?

[gopalchouhan]

• Please check if YAPRC server is set up correctly. You can use yab tool to send the grpc request to yarpc server to check if it is working as expected or not. Once you verify it is working, you can mimic the headers.
• rpc-caller-procedure is not supported. The related code was added as an experiment, and this code needs to be cleaned up. Thank you for reminding us.

[antstorm]

@gopalchouhan thanks, I'll try to use yab to check if the server is configured properly (I assume it is, since it also has a Thrift/TChannel endpoint that I used before.

Can you please expand on how yarpc determines which procedure is being called?

[antstorm]

Ok, figured it out — the content type had to be proto, not application/proto. The error message could have been a bit more legible — maybe include the available procedures?

[gopalchouhan]

I believe error message is clear enough here. Given that issue look to be resolved, closing the issue.