Need to expose generated protobuf C++ headers

[abergmeier-dsfishlabs]

… so they can actually be accessed from other libraries.

[grpc-kokoro]

Thanks for your pull request. The automated tests will run as soon as one of the admins verifies this change is ok to test.

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[smr277]

How would you use this with, say, a cc_library? Would you just include it in deps as ":<proto_library>"?

[abergmeier]

Would you just include it in deps as ":"?

Exactly:

cc_proto_library(
  name = "proto_foo",
)

cc_library(
  name = "foo",
  deps = [
    ":proto_foo",
  ]

I actually use it like this when working downstream with Bazel workers. That's what it is needed for.

[abergmeier-dsfishlabs]

We signed it!

[xfxyjwf]

@abergmeier You probably need to make another pull request using that account that signed the CLA?

[abergmeier-dsfishlabs]

On the bazel repo it was only necessary to run the cla-bot again. Tadaaaaa.

[googlebot]

CLAs look good, thanks!

[abergmeier-dsfishlabs]

@davidzchen So are you tracking this manually then?

[abergmeier-dsfishlabs]

Anyone looking at that?

[grpc-kokoro]

Thanks for your pull request. The automated tests will run as soon as one of the admins verifies this change is ok for us to run on our infrastructure.

[xfxyjwf]

LG. Thanks!

[abergmeier-dsfishlabs]

@davidzchen ping

[ghost]

For others who are trying to integrate C++ protobufs using Bazel into their own projects. I was able to invoke protobuf's protobuf.bzl file with the following recipe:

Under WORKSPACE add protobuf repo:

new_local_repository(
    name = "protobuf",
    build_file = "third_party/protobuf/BUILD",
    path = "third_party/protobuf"
)

Under your BUILD bazel file in your local project:

load("@protobuf//:protobuf.bzl", "cc_proto_library")
cc_proto_library(
  name = "my_proto",
  srcs = ["my.proto"],
  default_runtime = "@protobuf//:protobuf",
  protoc = "@protobuf//:protoc",
  visibility = ["//visibility:public"],
)

Then, in the command line, simply do: bazel build :my_proto

... and Bazel will automatically generate the file. When including headers, make sure to include relative to where the WORKSPACE file is located. For me, to access the autogenerated protobuf files, I did:

#include "lib/my_proto.pb.h"

As noted in the protobuf.bzl file, this is a temporary workaround until Bazel has general support for the proto_library() command.