go-bazel

A Bazel scaffold template for golang / protobuf+grpc mono repository.

Features

• Multi golang microservices in the mono repo
• Single build pipeline
• Shared golang library
• Shared grpc/protobuf library
• Automatic release GitHub workflow action
  • macOS and Linux builds

A hypothetical setup

• A cli ServiceA calling ServiceB grpc method Sum(int32, inte32)
• A ServiceB serving the Sum method over grpc.

Step 1: Install Bazel

• macOS: https://bazel.build/install/os-x
• Ubuntu: https://bazel.build/install/ubuntu

Step 2: Build it

Run the complete build pipeline using:

bazel build //...

Note: The first build will take a moment. No worries, you will see the Bazel mono repo benefits later.

Step 3: Run to see the result

In one terminal, run the grpc serving ServiceA:

bazel run services/servicea :42042

In another terminal, run the client ServiceB:

bazel run services/serviceb :42042

You should see the result. Protobuf + grpc built, services binaries built as well. The built binaries are in the /bazel-bin directory in their respective sub directories.

Protobuf/grpc caveats

There is a little caveat with proto when using Bazel. The golang generated proto files are in the bazel-bin build folder (as they are result of the build, not a source). So they are not accessible to your IDE. There is an official issue. Until solved, the workaround is:

• For every proto service:

• Run Bazel to generate the proto golang implementation:

  bazel run //proto/[service]
  

• Manually copy generated implementation back to the proto/[service] directory:

  cp ./bazel-bin/proto/[service]/[service]_go_proto_/github.com/jankremlacek/go-bazel/proto/[service]/*.pb.go ./proto/[service]/
  

• Also, you have to exclude the copied file from the Bazel build. Create file /proto/[service]/.bazelignore and put there all generated [filename].pb.go files.

Note: Of course, this process can be automated.

Additonal commands

• Build BUILD.bazel build files using Gazelle:

  bazel run //:gazelle
  

• Update Gazelle golang dependencies using:

  bazel run //:gazelle-update-repos
  

• Test whole pipeline using:

  bazel test //...
  

Additional resources

• Bazel official website
• Bazel at GitHub
• Gazelle at GitHub