# -*- mode: python; -*- PYTHON-PREPROCESSING-REQUIRED
def _gen_dir(ctx):
if ctx.attr.include == None:
return ""
if not ctx.attr.include:
return ctx.label.package
if not ctx.label.package:
return ctx.attr.include
return ctx.label.package + '/' + ctx.attr.include
def _cc_outs(srcs):
return [s[:-len(".proto")] + ".pb.h" for s in srcs] + \
[s[:-len(".proto")] + ".pb.cc" for s in srcs]
def _py_outs(srcs):
return [s[:-len(".proto")] + "_pb2.py" for s in srcs]
def _proto_gen_impl(ctx):
"""General implementation for generating protos"""
srcs = ctx.files.srcs
deps = []
deps += ctx.files.srcs
gen_dir = _gen_dir(ctx)
import_flags = ["-I" + gen_dir]
for dep in ctx.attr.deps:
import_flags += dep.proto.import_flags
deps += dep.proto.deps
args = []
if ctx.attr.gen_cc:
args += ["--cpp_out=" + ctx.var["GENDIR"] + "/" + gen_dir]
if ctx.attr.gen_py:
args += ["--python_out=" + ctx.var["GENDIR"] + "/" + gen_dir]
if args:
ctx.action(
inputs=srcs + deps,
outputs=ctx.outputs.outs,
arguments=args + import_flags + [s.path for s in srcs],
executable=ctx.executable.protoc,
)
return struct(
proto=struct(
srcs=srcs,
import_flags=import_flags,
deps=deps,
),
)
_proto_gen = rule(
attrs = {
"srcs": attr.label_list(allow_files = True),
"deps": attr.label_list(providers = ["proto"]),
"include": attr.string(),
"protoc": attr.label(
executable = True,
single_file = True,
mandatory = True,
),
"gen_cc": attr.bool(),
"gen_py": attr.bool(),
"outs": attr.output_list(),
},
output_to_genfiles = True,
implementation = _proto_gen_impl,
)
def cc_proto_library(
name,
srcs=[],
deps=[],
cc_libs=[],
include=None,
protoc=":protoc",
internal_bootstrap_hack=False,
**kargs):
"""Bazel rule to create a C++ protobuf library from proto source files
Args:
name: the name of the cc_proto_library.
srcs: the .proto files of the cc_proto_library.
deps: a list of dependency labels; must be cc_proto_library.
cc_libs: a list of other cc_library targets depended by the generated
cc_library.
include: a string indicating the include path of the .proto files.
protoc: the label of the protocol compiler to generate the sources.
internal_bootstrap_hack: a flag indicate the cc_proto_library is used only
for bootstraping. When it is set to True, no files will be generated.
The rule will simply be a provider for .proto files, so that other
cc_proto_library can depend on it.
**kargs: other keyword arguments that are passed to cc_library.
"""
if internal_bootstrap_hack:
# For pre-checked-in generated files, we add the internal_bootstrap_hack
# which will skip the codegen action.
_proto_gen(
name=name + "_genproto",
srcs=srcs,
deps=[s + "_genproto" for s in deps],
include=include,
protoc=protoc,
)
# An empty cc_library to make rule dependency consistent.
native.cc_library(
name=name,
**kargs)
return
outs = _cc_outs(srcs)
_proto_gen(
name=name + "_genproto",
srcs=srcs,
deps=[s + "_genproto" for s in deps],
include=include,
protoc=protoc,
gen_cc=1,
outs=outs,
)
includes = []
if include != None:
includes = [include]
native.cc_library(
name=name,
srcs=outs,
deps=cc_libs + deps,
includes=includes,
**kargs)
