Build protoc from source, rather than using a binary protoc.

Migrate to using the Bazel rules_proto and rules_python packages to build protocol buffers, rather than rolling our own protobuf generation code.

Fixes tensorflow#327

WORKSPACE

@@ -1,7 +1,7 @@
 """Workspace file for lingvo."""
 
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
-load("//lingvo:repo.bzl", "cc_tf_configure", "icu", "lingvo_protoc_deps", "lingvo_testonly_deps")
+load("//lingvo:repo.bzl", "cc_tf_configure", "icu", "lingvo_testonly_deps")
 
 http_archive(
     name = "org_tensorflow",
@@ -14,10 +14,45 @@ load("@org_tensorflow//tensorflow/tools/toolchains/remote_config:configs.bzl", "
 
 initialize_rbe_configs()
 
+http_archive(
+    name = "rules_python",
+    sha256 = "5868e73107a8e85d8f323806e60cad7283f34b32163ea6ff1020cf27abef6036",
+    strip_prefix = "rules_python-0.25.0",
+    url = "https://github.com/bazelbuild/rules_python/releases/download/0.25.0/rules_python-0.25.0.tar.gz",
+)
+
+load("@rules_python//python:repositories.bzl", "py_repositories")
+
+py_repositories()
+
+http_archive(
+    name = "com_google_protobuf",
+    sha256 = "75be42bd736f4df6d702a0e4e4d30de9ee40eac024c4b845d17ae4cc831fe4ae",
+    strip_prefix = "protobuf-21.7",
+    urls = [
+        "https://mirror.bazel.build/github.com/protocolbuffers/protobuf/archive/v21.7.tar.gz",
+        "https://github.com/protocolbuffers/protobuf/archive/v21.7.tar.gz",
+    ],
+)
+load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
+
+protobuf_deps()
+
+http_archive(
+    name = "rules_proto",
+    sha256 = "dc3fb206a2cb3441b485eb1e423165b231235a1ea9b031b4433cf7bc1fa460dd",
+    strip_prefix = "rules_proto-5.3.0-21.7",
+    urls = [
+        "https://github.com/bazelbuild/rules_proto/archive/refs/tags/5.3.0-21.7.tar.gz",
+    ],
+)
+load("@rules_proto//proto:repositories.bzl", "rules_proto_dependencies", "rules_proto_toolchains")
+rules_proto_dependencies()
+rules_proto_toolchains()
+
+
 cc_tf_configure()
 
 lingvo_testonly_deps()
 
-lingvo_protoc_deps()
-
 icu()

lingvo/BUILD

@@ -5,7 +5,8 @@ load(
 
 # Placeholder: load py_library
 # Placeholder: load py_test
-load("//lingvo:lingvo.bzl", "pytype_library", "pytype_strict_library")
+load("//lingvo:lingvo.bzl", "pytype_library", "pytype_strict_library",
+     "WELL_KNOWN_PROTO_LIBS")
 
 package(default_visibility = ["//visibility:public"])
 
@@ -327,10 +328,38 @@ lingvo_py_binary(
     ],
 )
 
+TF_PROTOS = [
+    "tensorflow/core/framework/tensor.proto",
+    "tensorflow/core/framework/versions.proto",
+    "tensorflow/core/framework/op_def.proto",
+    "tensorflow/core/framework/resource_handle.proto",
+    "tensorflow/core/framework/function.proto",
+    "tensorflow/core/framework/graph_debug_info.proto",
+    "tensorflow/core/framework/node_def.proto",
+    "tensorflow/core/framework/graph.proto",
+    "tensorflow/core/framework/attr_value.proto",
+    "tensorflow/core/framework/variable.proto",
+    "tensorflow/core/framework/full_type.proto",
+    "tensorflow/core/framework/tensor_shape.proto",
+    "tensorflow/core/framework/types.proto",
+    "tensorflow/core/protobuf/trackable_object_graph.proto",
+    "tensorflow/core/protobuf/saver.proto",
+    "tensorflow/core/protobuf/struct.proto",
+    "tensorflow/core/protobuf/saved_object_graph.proto",
+    "tensorflow/core/protobuf/meta_graph.proto",
+]
+
+proto_library(
+    name = "tf_protos",
+    srcs = TF_PROTOS,
+    strip_import_prefix = "/lingvo",
+    deps = WELL_KNOWN_PROTO_LIBS,
+)
+
 genrule(
     name = "tf_dot_protos",
     srcs = [],
-    outs = ["tf_protos.tar"],
+    outs = TF_PROTOS,
     cmd =
         "$(location //lingvo/tools:" +
         "generate_tf_dot_protos) $(location " +

lingvo/lingvo.bzl

@@ -1,5 +1,7 @@
 """Implements custom rules for Lingvo."""
 
+load("@rules_python//python:proto.bzl", "py_proto_library")
+
 def tf_copts():
     #  "-Wno-sign-compare", "-mavx" removed for compat with aarch64
     return ["-std=c++17"] + select({
@@ -107,65 +109,52 @@ def lingvo_cuda_py_test(name, tags = [], deps = [], **kwargs):
         **kwargs
     )
 
-def _proto_gen_cc_src(name, basename):
-    native.genrule(
-        name = name,
-        srcs = [basename + ".proto"],
-        outs = [basename + ".pb.cc", basename + ".pb.h"],
-        tools = [
-            "@protobuf_protoc//:protoc_bin",
-            "//lingvo:tf_dot_protos",
-        ],
-        # TODO(drpng): only unpack if tf_proto dependency is requested.
-        cmd = """
-          mkdir -p $(@D)/tf_proto.$$$$;
-          tar -C $(@D)/tf_proto.$$$$ -xf $(location //lingvo:tf_dot_protos);
-          $(location @protobuf_protoc//:protoc_bin) --proto_path=$(@D)/tf_proto.$$$$  --proto_path=. --cpp_out=$(GENDIR) $(<);
-          rm -rf $(@D)/tf_proto.$$$$
-        """,
-    )
-
-def _proto_gen_py_src(name, basename):
-    native.genrule(
-        name = name,
-        srcs = [basename + ".proto"],
-        outs = [basename + "_pb2.py"],
-        tools = [
-            "@protobuf_protoc//:protoc_bin",
-            "//lingvo:tf_dot_protos",
-        ],
-        # TODO(drpng): only unpack if tf_proto dependency is requested.
-        cmd = """
-          mkdir -p $(@D)/tf_proto.$$$$;
-          tar -C $(@D)/tf_proto.$$$$ -xf $(location //lingvo:tf_dot_protos);
-          $(location @protobuf_protoc//:protoc_bin) --proto_path=$(@D)/tf_proto.$$$$ --proto_path=. --python_out=$(GENDIR) $(<);
-          rm -rf $(@D)/tf_proto.$$$$
-        """,
-    )
+WELL_KNOWN_PROTO_LIBS = [
+    "@com_google_protobuf//:any_proto",
+    "@com_google_protobuf//:api_proto",
+    "@com_google_protobuf//:compiler_plugin_proto",
+    "@com_google_protobuf//:descriptor_proto",
+    "@com_google_protobuf//:duration_proto",
+    "@com_google_protobuf//:empty_proto",
+    "@com_google_protobuf//:field_mask_proto",
+    "@com_google_protobuf//:source_context_proto",
+    "@com_google_protobuf//:struct_proto",
+    "@com_google_protobuf//:timestamp_proto",
+    "@com_google_protobuf//:type_proto",
+    "@com_google_protobuf//:wrappers_proto",
+]
 
 def lingvo_proto_cc(name, src, deps = []):
     # TODO(drpng): only works with proto with no deps within lingvo.
     _unused = [deps]
     basename = src.replace(".proto", "")
-    _proto_gen_cc_src(name + "_gencc", basename)
-    lingvo_cc_library(
+    native.proto_library(
         name = name,
-        srcs = [basename + ".pb.cc"],
-        hdrs = [basename + ".pb.h"],
+        srcs = [src],
+        deps = [
+             "//lingvo:tf_protos",
+        ] + WELL_KNOWN_PROTO_LIBS,
     )
-    lingvo_cc_library(
-        name = "%s_cc" % name,
-        deps = [":%s" % name],
+    native.cc_proto_library(
+        name = name + "_cc",
+        deps = [":" + name]
     )
 
+
 def lingvo_proto_py(name, src, deps = []):
     # TODO(drpng): only works with proto with no deps within lingvo.
     _unused = [deps]
     basename = src.replace(".proto", "")
-    _proto_gen_py_src(name + "_genpy", basename)
-    native.py_library(
+    native.proto_library(
+        name = name + "_pyproto",
+        srcs = [src],
+        deps = [
+             "//lingvo:tf_protos",
+        ] + WELL_KNOWN_PROTO_LIBS,
+    )
+    py_proto_library(
         name = name,
-        srcs = [basename + "_pb2.py"],
+        deps = [name + "_pyproto"],
     )
 
 # Placeholders to use until bazel supports pytype_{,strict_}{library,test,binary}.

lingvo/repo.bzl

@@ -221,22 +221,6 @@ cc_library(
             strip_prefix = "googletest-release-1.10.0",
         )
 
-def lingvo_protoc_deps():
-    http_archive(
-        name = "protobuf_protoc",
-        build_file_content = """
-filegroup(
-    name = "protoc_bin",
-    srcs = ["bin/protoc"],
-    visibility = ["//visibility:public"],
-)
-""",
-        urls = [
-            "https://github.com/protocolbuffers/protobuf/releases/download/v21.9/protoc-21.9-linux-x86_64.zip",
-        ],
-        sha256 = "3cd951aff8ce713b94cde55e12378f505f2b89d47bf080508cf77e3934f680b6",
-    )
-
 def icu():
     third_party_http_archive(
         name = "icu",

lingvo/tools/generate_tf_dot_protos.sh

@@ -31,7 +31,3 @@ mkdir -p ${dest}/tensorflow/core/framework
 mkdir -p ${dest}/tensorflow/core/protobuf
 
 ${binary} ${dest}
-
-# genrule requires statically determined outputs, so we package all
-# into a single file.
-tar -C ${dest} -cf ${dest}/tf_protos.tar tensorflow/core/{framework,protobuf}