From 79f54e9d5783a2d521f20a5f5c0e11496709abb3 Mon Sep 17 00:00:00 2001
From: Richard Belleville <rbellevi@google.com>
Date: Mon, 19 Oct 2020 23:39:01 -0700
Subject: [PATCH] Include well known types in bazel build

---
 tools/distrib/python/grpcio_tools/BUILD.bazel | 10 +-
 .../python/grpcio_tools/grpcio_tools.bzl      | 91 +++++++++++++++++++
 2 files changed, 100 insertions(+), 1 deletion(-)
 create mode 100644 tools/distrib/python/grpcio_tools/grpcio_tools.bzl

diff --git a/tools/distrib/python/grpcio_tools/BUILD.bazel b/tools/distrib/python/grpcio_tools/BUILD.bazel
index a23975feeb8..eaf4895b49b 100644
--- a/tools/distrib/python/grpcio_tools/BUILD.bazel
+++ b/tools/distrib/python/grpcio_tools/BUILD.bazel
@@ -19,6 +19,7 @@ package(default_visibility = [
 ])
 
 load("//bazel:cython_library.bzl", "pyx_library")
+load("grpcio_tools.bzl", "internal_copied_filegroup")
 
 cc_library(
     name = "protoc_lib",
@@ -37,6 +38,13 @@ pyx_library(
     deps = [":protoc_lib"],
 )
 
+internal_copied_filegroup(
+   name = "well_known_protos",
+   srcs = ["@com_google_protobuf//:well_known_protos"],
+   strip_prefix = "src/",
+   dest = "grpc_tools/_proto/",
+)
+
 py_library(
     name = "grpc_tools",
     srcs = [
@@ -50,5 +58,5 @@ py_library(
         "//src/python/grpcio/grpc:grpcio",
         "@com_google_protobuf//:protobuf_python",
     ],
-    data = glob(["grpc_tools/_proto/**/*"]),
+    data = [":well_known_protos"],
 )
diff --git a/tools/distrib/python/grpcio_tools/grpcio_tools.bzl b/tools/distrib/python/grpcio_tools/grpcio_tools.bzl
new file mode 100644
index 00000000000..8b6c121ffa6
--- /dev/null
+++ b/tools/distrib/python/grpcio_tools/grpcio_tools.bzl
@@ -0,0 +1,91 @@
+# Copyright 2020 The gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+def _generate_copied_files_impl(ctx):
+    srcs = ctx.attr.srcs[0]
+    strip_prefix = ctx.attr.strip_prefix
+    dest = ctx.attr.dest
+
+    outs = []
+    for f in srcs.files.to_list():
+        destination_path = f.path
+        if f.path.startswith("external"):
+            external_separator = f.path.find("/")
+            repository_separator = f.path.find("/", external_separator + 1)
+            destination_path = f.path[repository_separator+1:]
+        if not destination_path.startswith(strip_prefix):
+            fail("File '{}' did not start with '{}'.".format(
+                    destination_path, strip_prefix))
+        destination_path = dest + destination_path[len(strip_prefix):]
+        destination_dir = destination_path.rfind("/")
+        out_file = ctx.actions.declare_file(destination_path)
+        outs.append(out_file)
+        ctx.actions.run_shell(
+            inputs = [f],
+            outputs = [out_file],
+            command = "mkdir -p {0} && cp {1} {2}".format(
+                    out_file.dirname, f.path, out_file.path),
+        )
+
+    return [DefaultInfo(files = depset(direct = outs))]
+
+
+_generate_copied_files = rule(
+    attrs = {
+        "srcs": attr.label_list(
+            mandatory = True,
+            allow_empty = False,
+        ),
+        "strip_prefix": attr.string(
+            default = "",
+        ),
+        "dest": attr.string(
+            mandatory = True,
+        )
+    },
+    implementation = _generate_copied_files_impl,
+)
+
+
+def internal_copied_filegroup(name, srcs, strip_prefix, dest):
+    """Copies a file group to the current package.
+
+    Useful for using an existing filegroup as a data dependency.
+
+    Args:
+      name: The name of the rule.
+      srcs: A single filegroup.
+      strip_prefix: An optional string to strip from the beginning
+        of the path of each file in the filegroup. Must end in a slash.
+      dest: The directory in which to put the files, relative to the
+        current package. Must end in a slash.
+    """
+    if len(srcs) != 1:
+        fail("srcs must be a single filegroup.")
+
+    if not dest.endswith("/"):
+        fail("dest must end with a '/' character.")
+
+    _symlink_target = name + "_symlink"
+    _generate_copied_files(
+        name = _symlink_target,
+        srcs = srcs,
+        strip_prefix = strip_prefix,
+        dest = dest,
+    )
+
+    native.filegroup(
+        name = name,
+        srcs = [":" + _symlink_target],
+    )