WIP: Add grpc-gateway support

Related to https://gitlab.com/gitlab-org/gitaly/issues/191

Experimenting in adding grpc-gateway, Swagger and auto-generated Ruby client support to gitaly-proto

Very impressive. So if I understand correctly, the changes in this MR are:

• run extra code generation plugin when building libs from .proto
• some of these code generator plugins use Java -> would be a development dependency for gitaly-proto only, not runtime, no Java needed for gitaly server / clients
• we would have to annotate each RPC to indicate what it's REST endpoint would be

added 1 commit

• 505b15aa - Feature: now generating a full API client

Compare with previous version

run extra code generation plugin when building libs from .proto

There are two new protoc generators

• a Go grpc Gateway generator (gateway/*.pb.gw.go), which generates the JSON to gRPC go server logic
• a Swagger generator, (swagger/*.swagger.json), which generators a Swagger definition of the JSON gateway

Once we have the Swagger generator, we're able to generator a native Ruby client (or client for any other major language, for that matter). In order to do this, we run swagger-codegen generate. Unfortunately, the Swagger generator is written in Java, so we have a build time dependency on Java.

we would have to annotate each RPC to indicate what it's REST endpoint would be

Yes, although this this is a fairly trivial thing to do. I did this for all the existing endpoints in a matter of minutes.

closed