blob: f3961f0a4197f5e2bb3e0d7ce1857bd120fe3eaf [file] [log] [blame]
"""Generates C++ grpc stubs from proto_library rules.
This is an internal rule used by cc_grpc_library, and shouldn't be used
directly.
"""
def generate_cc_impl(ctx):
"""Implementation of the generate_cc rule."""
protos = [f for src in ctx.attr.srcs for f in src.proto.direct_sources]
includes = [f for src in ctx.attr.srcs for f in src.proto.transitive_imports]
outs = []
if ctx.executable.plugin:
outs += [proto.basename[:-len(".proto")] + ".grpc.pb.h" for proto in protos]
outs += [proto.basename[:-len(".proto")] + ".grpc.pb.cc" for proto in protos]
else:
outs += [proto.basename[:-len(".proto")] + ".pb.h" for proto in protos]
outs += [proto.basename[:-len(".proto")] + ".pb.cc" for proto in protos]
out_files = [ctx.new_file(out) for out in outs]
# The following should be replaced with ctx.configuration.buildout
# whenever this is added to Skylark.
dir_out = out_files[0].dirname[:-len(protos[0].dirname)]
arguments = []
if ctx.executable.plugin:
arguments += ["--plugin=protoc-gen-PLUGIN=" + ctx.executable.plugin.path]
arguments += ["--PLUGIN_out=" + ",".join(ctx.attr.flags) + ":" + dir_out]
additional_input = [ctx.executable.plugin]
else:
arguments += ["--cpp_out=" + ",".join(ctx.attr.flags) + ":" + dir_out]
additional_input = []
arguments += ["-I{0}={0}".format(include.path) for include in includes]
arguments += [proto.path for proto in protos]
# create a list of well known proto files if the argument is non-None
well_known_proto_files = []
if ctx.attr.well_known_protos:
f = ctx.attr.well_known_protos.files.to_list()[0].dirname
if f != "external/submodule_protobuf/src/google/protobuf":
print("Error: Only @submodule_protobuf//:well_known_protos is supported")
else:
# f points to "external/submodule_protobuf/src/google/protobuf"
# add -I argument to protoc so it knows where to look for the proto files.
arguments += ["-I{0}".format(f + "/../..")]
well_known_proto_files = [f for f in ctx.attr.well_known_protos.files]
ctx.action(
inputs = protos + includes + additional_input + well_known_proto_files,
outputs = out_files,
executable = ctx.executable._protoc,
arguments = arguments,
)
return struct(files=set(out_files))
generate_cc = rule(
attrs = {
"srcs": attr.label_list(
mandatory = True,
non_empty = True,
providers = ["proto"],
),
"plugin": attr.label(
executable = True,
providers = ["files_to_run"],
cfg = "host",
),
"flags": attr.string_list(
mandatory = False,
allow_empty = True,
),
"well_known_protos" : attr.label(
mandatory = False,
),
"_protoc": attr.label(
default = Label("//external:protocol_compiler"),
executable = True,
cfg = "host",
),
},
# We generate .h files, so we need to output to genfiles.
output_to_genfiles = True,
implementation = generate_cc_impl,
)