load("@bazel_skylib//:lib.bzl", "versions")
def _GetPath(ctx, path):
if ctx.label.workspace_root:
return ctx.label.workspace_root + '/' + path
else:
return path
def _IsNewExternal(ctx):
# Bazel 0.4.4 and older have genfiles paths that look like:
# bazel-out/local-fastbuild/genfiles/external/repo/foo
# After the exec root rearrangement, they look like:
# ../repo/bazel-out/local-fastbuild/genfiles/foo
return ctx.label.workspace_root.startswith("../")
def _GenDir(ctx):
if _IsNewExternal(ctx):
# We are using the fact that Bazel 0.4.4+ provides repository-relative paths
# for ctx.genfiles_dir.
return ctx.genfiles_dir.path + (
"/" + ctx.attr.includes[0] if ctx.attr.includes and ctx.attr.includes[0] else "")
# This means that we're either in the old version OR the new version in the local repo.
# Either way, appending the source path to the genfiles dir works.
return ctx.var["GENDIR"] + "/" + _SourceDir(ctx)
def _SourceDir(ctx):
if not ctx.attr.includes:
return ctx.label.workspace_root
if not ctx.attr.includes[0]:
return _GetPath(ctx, ctx.label.package)
if not ctx.label.package:
return _GetPath(ctx, ctx.attr.includes[0])
return _GetPath(ctx, ctx.label.package + '/' + ctx.attr.includes[0])
def _CcHdrs(srcs, use_grpc_plugin=False):
ret = [s[:-len(".proto")] + ".pb.h" for s in srcs]
if use_grpc_plugin:
ret += [s[:-len(".proto")] + ".grpc.pb.h" for s in srcs]
return ret
def _CcSrcs(srcs, use_grpc_plugin=False):
ret = [s[:-len(".proto")] + ".pb.cc" for s in srcs]
if use_grpc_plugin:
ret += [s[:-len(".proto")] + ".grpc.pb.cc" for s in srcs]
return ret
def _CcOuts(srcs, use_grpc_plugin=False):
return _CcHdrs(srcs, use_grpc_plugin) + _CcSrcs(srcs, use_grpc_plugin)
def _PyOuts(srcs, use_grpc_plugin=False):
ret = [s[:-len(".proto")] + "_pb2.py" for s in srcs]
if use_grpc_plugin:
ret += [s[:-len(".proto")] + "_pb2_grpc.py" for s in srcs]
return ret
def _RelativeOutputPath(path, include, dest=""):
if include == None:
return path
if not path.startswith(include):
fail("Include path %s isn't part of the path %s." % (include, path))
if include and include[-1] != '/':
include = include + '/'
if dest and dest[-1] != '/':
dest = dest + '/'
path = path[len(include):]
return dest + path
def _proto_gen_impl(ctx):
"""General implementation for generating protos"""
srcs = ctx.files.srcs
deps = []
deps += ctx.files.srcs
source_dir = _SourceDir(ctx)
gen_dir = _GenDir(ctx).rstrip('/')
if source_dir:
import_flags = ["-I" + source_dir, "-I" + gen_dir]
else:
import_flags = ["-I."]
for dep in ctx.attr.deps:
import_flags += dep.proto.import_flags
deps += dep.proto.deps
if not ctx.attr.gen_cc and not ctx.attr.gen_py and not ctx.executable.plugin:
return struct(
proto=struct(
srcs=srcs,
import_flags=import_flags,
deps=deps,
),
)
for src in srcs:
args = []
in_gen_dir = src.root.path == gen_dir
if in_gen_dir:
import_flags_real = []
for f in depset(import_flags):
path = f.replace('-I', '')
import_flags_real.append('-I$(realpath -s %s)' % path)
outs = []
use_grpc_plugin = (ctx.attr.plugin_language == "grpc" and ctx.attr.plugin)
path_tpl = "$(realpath %s)" if in_gen_dir else "%s"
if ctx.attr.gen_cc:
args += [("--cpp_out=" + path_tpl) % gen_dir]
outs.extend(_CcOuts([src.basename], use_grpc_plugin=use_grpc_plugin))
if ctx.attr.gen_py:
args += [("--python_out=" + path_tpl) % gen_dir]
outs.extend(_PyOuts([src.basename], use_grpc_plugin=use_grpc_plugin))
outs = [ctx.actions.declare_file(out, sibling=src) for out in outs]
inputs = [src] + deps
if ctx.executable.plugin:
plugin = ctx.executable.plugin
lang = ctx.attr.plugin_language
if not lang and plugin.basename.startswith('protoc-gen-'):
lang = plugin.basename[len('protoc-gen-'):]
if not lang:
fail("cannot infer the target language of plugin", "plugin_language")
outdir = "." if in_gen_dir else gen_dir
if ctx.attr.plugin_options:
outdir = ",".join(ctx.attr.plugin_options) + ":" + outdir
args += [("--plugin=protoc-gen-%s=" + path_tpl) % (lang, plugin.path)]
args += ["--%s_out=%s" % (lang, outdir)]
inputs += [plugin]
if not in_gen_dir:
ctx.action(
inputs=inputs,
outputs=outs,
arguments=args + import_flags + [src.path],
executable=ctx.executable.protoc,
mnemonic="ProtoCompile",
use_default_shell_env=True,
)
else:
for out in outs:
orig_command = " ".join(
["$(realpath %s)" % ctx.executable.protoc.path] + args +
import_flags_real + ["-I.", src.basename])
command = ";".join([
'CMD="%s"' % orig_command,
"cd %s" % src.dirname,
"${CMD}",
"cd -",
])
generated_out = '/'.join([gen_dir, out.basename])
if generated_out != out.path:
command += ";mv %s %s" % (generated_out, out.path)
ctx.action(
inputs=inputs + [ctx.executable.protoc],
outputs=[out],
command=command,
mnemonic="ProtoCompile",
use_default_shell_env=True,
)
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"]),
"includes": attr.string_list(),
"protoc": attr.label(
cfg = "host",
executable = True,
allow_single_file = True,
mandatory = True,
),
"plugin": attr.label(
cfg = "host",
allow_files = True,
executable = True,
),
"plugin_language": attr.string(),
"plugin_options": attr.string_list(),
"gen_cc": attr.bool(),
"gen_py": attr.bool(),
"outs": attr.output_list(),
},
output_to_genfiles = True,
implementation = _proto_gen_impl,
)
"""Generates codes from Protocol Buffers definitions.
This rule helps you to implement Skylark macros specific to the target
language. You should prefer more specific `cc_proto_library `,
`py_proto_library` and others unless you are adding such wrapper macros.
Args:
srcs: Protocol Buffers definition files (.proto) to run the protocol compiler
against.
deps: a list of dependency labels; must be other proto libraries.
includes: a list of include paths to .proto files.
protoc: the label of the protocol compiler to generate the sources.
plugin: the label of the protocol compiler plugin to be passed to the protocol
compiler.
plugin_language: the language of the generated sources
plugin_options: a list of options to be passed to the plugin
gen_cc: generates C++ sources in addition to the ones from the plugin.
gen_py: generates Python sources in addition to the ones from the plugin.
outs: a list of labels of the expected outputs from the protocol compiler.
"""
def cc_proto_library(
name,
srcs=[],
deps=[],
cc_libs=[],
include=None,
protoc="@com_google_protobuf//:protoc",
internal_bootstrap_hack=False,
use_grpc_plugin=False,
default_runtime="@com_google_protobuf//:protobuf",
**kargs):
"""Bazel rule to create a C++ protobuf library from proto source files
NOTE: the rule is only an internal workaround to generate protos. The
interface may change and the rule may be removed when bazel has introduced
the native rule.
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.
use_grpc_plugin: a flag to indicate whether to call the grpc C++ plugin
when processing the proto files.
default_runtime: the implicitly default runtime which will be depended on by
the generated cc_library target.
**kargs: other keyword arguments that are passed to cc_library.
"""
includes = []
if include != None:
includes = [include]
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],
includes=includes,
protoc=protoc,
visibility=["//visibility:public"],
)
# An empty cc_library to make rule dependency consistent.
native.cc_library(
name=name,
**kargs)
return
grpc_cpp_plugin = None
if use_grpc_plugin:
grpc_cpp_plugin = "//external:grpc_cpp_plugin"
gen_srcs = _CcSrcs(srcs, use_grpc_plugin)
gen_hdrs = _CcHdrs(srcs, use_grpc_plugin)
outs = gen_srcs + gen_hdrs
proto_gen(
name=name + "_genproto",
srcs=srcs,
deps=[s + "_genproto" for s in deps],
includes=includes,
protoc=protoc,
plugin=grpc_cpp_plugin,
plugin_language="grpc",
gen_cc=1,
outs=outs,
visibility=["//visibility:public"],
)
if default_runtime and not default_runtime in cc_libs:
cc_libs = cc_libs + [default_runtime]
if use_grpc_plugin:
cc_libs = cc_libs + ["//external:grpc_lib"]
native.cc_library(
name=name,
srcs=gen_srcs,
hdrs=gen_hdrs,
deps=cc_libs + deps,
includes=includes,
**kargs)
def internal_gen_well_known_protos_java(srcs):
"""Bazel rule to generate the gen_well_known_protos_java genrule
Args:
srcs: the well known protos
"""
root = Label("%s//protobuf_java" % (native.repository_name())).workspace_root
pkg = native.package_name() + "/" if native.package_name() else ""
if root == "":
include = " -I%ssrc " % pkg
else:
include = " -I%s/%ssrc " % (root, pkg)
native.genrule(
name = "gen_well_known_protos_java",
srcs = srcs,
outs = [
"wellknown.srcjar",
],
cmd = "$(location :protoc) --java_out=$(@D)/wellknown.jar" +
" %s $(SRCS) " % include +
" && mv $(@D)/wellknown.jar $(@D)/wellknown.srcjar",
tools = [":protoc"],
)
def internal_copied_filegroup(name, srcs, strip_prefix, dest, **kwargs):
"""Macro to copy files to a different directory and then create a filegroup.
This is used by the //:protobuf_python py_proto_library target to work around
an issue caused by Python source files that are part of the same Python
package being in separate directories.
Args:
srcs: The source files to copy and add to the filegroup.
strip_prefix: Path to the root of the files to copy.
dest: The directory to copy the source files into.
**kwargs: extra arguments that will be passesd to the filegroup.
"""
outs = [_RelativeOutputPath(s, strip_prefix, dest) for s in srcs]
native.genrule(
name = name + "_genrule",
srcs = srcs,
outs = outs,
cmd = " && ".join(
["cp $(location %s) $(location %s)" %
(s, _RelativeOutputPath(s, strip_prefix, dest)) for s in srcs]),
)
native.filegroup(
name = name,
srcs = outs,
**kwargs)
def py_proto_library(
name,
srcs=[],
deps=[],
py_libs=[],
py_extra_srcs=[],
include=None,
default_runtime="@com_google_protobuf//:protobuf_python",
protoc="@com_google_protobuf//:protoc",
use_grpc_plugin=False,
**kargs):
"""Bazel rule to create a Python protobuf library from proto source files
NOTE: the rule is only an internal workaround to generate protos. The
interface may change and the rule may be removed when bazel has introduced
the native rule.
Args:
name: the name of the py_proto_library.
srcs: the .proto files of the py_proto_library.
deps: a list of dependency labels; must be py_proto_library.
py_libs: a list of other py_library targets depended by the generated
py_library.
py_extra_srcs: extra source files that will be added to the output
py_library. This attribute is used for internal bootstrapping.
include: a string indicating the include path of the .proto files.
default_runtime: the implicitly default runtime which will be depended on by
the generated py_library target.
protoc: the label of the protocol compiler to generate the sources.
use_grpc_plugin: a flag to indicate whether to call the Python C++ plugin
when processing the proto files.
**kargs: other keyword arguments that are passed to cc_library.
"""
outs = _PyOuts(srcs, use_grpc_plugin)
includes = []
if include != None:
includes = [include]
grpc_python_plugin = None
if use_grpc_plugin:
grpc_python_plugin = "//external:grpc_python_plugin"
# Note: Generated grpc code depends on Python grpc module. This dependency
# is not explicitly listed in py_libs. Instead, host system is assumed to
# have grpc installed.
proto_gen(
name=name + "_genproto",
srcs=srcs,
deps=[s + "_genproto" for s in deps],
includes=includes,
protoc=protoc,
gen_py=1,
outs=outs,
visibility=["//visibility:public"],
plugin=grpc_python_plugin,
plugin_language="grpc"
)
if default_runtime and not default_runtime in py_libs + deps:
py_libs = py_libs + [default_runtime]
native.py_library(
name=name,
srcs=outs+py_extra_srcs,
deps=py_libs+deps,
imports=includes,
**kargs)
def internal_protobuf_py_tests(
name,
modules=[],
**kargs):
"""Bazel rules to create batch tests for protobuf internal.
Args:
name: the name of the rule.
modules: a list of modules for tests. The macro will create a py_test for
each of the parameter with the source "google/protobuf/%s.py"
kargs: extra parameters that will be passed into the py_test.
"""
for m in modules:
s = "python/google/protobuf/internal/%s.py" % m
native.py_test(
name="py_%s" % m,
srcs=[s],
main=s,
**kargs)
def check_protobuf_required_bazel_version():
"""For WORKSPACE files, to check the installed version of bazel.
This ensures bazel supports our approach to proto_library() depending on a
copied filegroup. (Fixed in bazel 0.5.4)
"""
versions.check(minimum_bazel_version = "0.5.4")
