Bazel rules for protobufs so that we don't have to regenerate generated protobuf code about cirq

[dabacon]

We no longer include the generated code because the engine code can use straight python dictionaries. However we should probably include bazel rules here anyway.

[vtomole]

Would like to help with this if i knew what it meant. I'm willing to learn Bazel but there are no tutorials for Python: https://docs.bazel.build/versions/master/getting-started.html

[vtomole]

Looks like Bazel rules are language agnostic. This is what I have in a BUILD file in cirq/api/google/v1

proto_library(
    name = "operations_proto",
    srcs = ["operations.proto"],
)

proto_library(
    name = "params_proto",
    srcs = ["params.proto"],
)

proto_library(
    name = "program_proto",
    srcs = ["program.proto"],
    deps = [
    "operations_proto",
    "params_proto",
    ],
)

[dabacon]

@vtomole have you check to see if this compiles in Bazel? If so I think we should add these (without making bazel a requirement of Cirq, but I think this will be useful...at least it will be inside of Google!)

[vtomole]

Bazel can compile it. Should I also send the WORKSPACE file? It's in Cirq/ and it contains

# This statement defines the @com_google_protobuf repo.
http_archive(
    name = "com_google_protobuf",
    sha256 = "cef7f1b5a7c5fba672bec2a319246e8feba471f04dcebfe362d55930ee7c1c30",
    strip_prefix = "protobuf-3.5.0",
    urls = ["https://github.com/google/protobuf/archive/v3.5.0.zip"],
)

Cirq$ bazel build //cirq/api/google/v1:program_proto
and friends can't succeed without it.

[Strilanc]

I had to kill the bazel step on travis because the jdk download started 404ing

[dabacon]

we have valid BUILD files, but aren't using or requiring bazel. I think we should close.