From 0cfe9550683b72b31cd40c35f6e34654562ee861 Mon Sep 17 00:00:00 2001
From: Richard Belleville <rbellevi@google.com>
Date: Fri, 22 Nov 2019 16:32:23 -0800
Subject: [PATCH] Add a simple unified importer

---
 .../python/grpcio_tools/grpc_tools/BUILD      |  3 ++
 .../grpcio_tools/grpc_tools/__init__.py       | 31 +++++++++++++++++++
 .../python/grpcio_tools/grpc_tools/protoc.py  |  1 -
 .../grpcio_tools/grpc_tools/protoc_test.py    | 15 +++++++--
 .../grpcio_tools/grpc_tools/simple.proto      | 21 +++++++++++++
 5 files changed, 67 insertions(+), 4 deletions(-)
 create mode 100644 tools/distrib/python/grpcio_tools/grpc_tools/simple.proto

diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/BUILD b/tools/distrib/python/grpcio_tools/grpc_tools/BUILD
index ecf45a42959..2aa111d2551 100644
--- a/tools/distrib/python/grpcio_tools/grpc_tools/BUILD
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/BUILD
@@ -3,6 +3,8 @@ package(default_visibility = ["//visibility:public"])
 
 load("//bazel:cython_library.bzl", "pyx_library")
 
+# TODO: Move this build file up a directory to ensure that this
+# points to '.', not a directory above the package root.
 NON_BAZEL_ROOT = "../"
 
 cc_library(
@@ -38,5 +40,6 @@ py_test(
   name = "protoc_test",
   srcs = ["protoc_test.py"],
   deps = ["//tools/distrib/python/grpcio_tools/grpc_tools:grpc_tools"],
+  data = ["simple.proto"],
   python_version = "PY3",
 )
diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/__init__.py b/tools/distrib/python/grpcio_tools/grpc_tools/__init__.py
index 5772620b602..d151994fc90 100644
--- a/tools/distrib/python/grpcio_tools/grpc_tools/__init__.py
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/__init__.py
@@ -11,3 +11,34 @@
 # 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.
+
+
+import importlib
+import os
+from .protoc import main
+
+# TODO: Get this thing to just give me the code via an FD.
+# TODO: Figure out what to do about STDOUT pollution.
+def import_protos(proto_path, project_root):
+    proto_basename = os.path.basename(proto_path)
+    proto_name, _ = os.path.splitext(proto_basename)
+    anchor_package = ".".join(os.path.normpath(os.path.dirname(proto_path)).split(os.sep))
+    original_dir = os.getcwd()
+    try:
+        os.chdir(os.path.join(original_dir, project_root))
+        return_value = protoc.main([
+          "grpc_tools.protoc",
+          "--proto_path=.",
+          "--python_out=.",
+          "--grpc_python_out=.",
+          proto_path
+        ])
+    finally:
+        os.chdir(original_dir)
+    if return_value != 0:
+      raise RuntimeError("Protoc failed.")
+    print("anchor_package: {}".format(anchor_package))
+    protos = importlib.import_module("{}.{}_pb2".format(anchor_package, proto_name))
+    services = importlib.import_module("{}.{}_pb2_grpc".format(anchor_package, proto_name))
+    return protos, services
+
diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py b/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
index 582cba0e396..18a5ef22874 100644
--- a/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/protoc.py
@@ -19,7 +19,6 @@ import sys
 
 from grpc_tools import _protoc_compiler
 
-
 def main(command_arguments):
     """Run the protocol buffer compiler with the given command-line arguments.
 
diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/protoc_test.py b/tools/distrib/python/grpcio_tools/grpc_tools/protoc_test.py
index 7de81ab62d0..01050d703ab 100644
--- a/tools/distrib/python/grpcio_tools/grpc_tools/protoc_test.py
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/protoc_test.py
@@ -4,15 +4,24 @@ from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 
+import importlib
+
 import unittest
 import grpc_tools
-from grpc_tools import protoc
+
+import os
+
 
 
 class ProtocTest(unittest.TestCase):
 
-  def test_protoc(self):
-      pass
+    def test_protoc(self):
+        # TODO: Get this thing to just give me the code via an FD.
+        # TODO: Figure out what to do about STDOUT pollution.
+        # TODO: How do we convert protoc failure into a Python error?
+        protos, services = grpc_tools.import_protos("grpc_tools/simple.proto", "tools/distrib/python/grpcio_tools/")
+        print(dir(protos))
+        print(dir(services))
 
 
 if __name__ == '__main__':
diff --git a/tools/distrib/python/grpcio_tools/grpc_tools/simple.proto b/tools/distrib/python/grpcio_tools/grpc_tools/simple.proto
new file mode 100644
index 00000000000..c4c21418e6f
--- /dev/null
+++ b/tools/distrib/python/grpcio_tools/grpc_tools/simple.proto
@@ -0,0 +1,21 @@
+syntax = "proto3";
+
+message SimpleMessage {
+  string msg = 1;
+  oneof personal_or_business {
+    bool personal = 2;
+    bool business = 3;
+  };
+};
+
+message SimpleMessageRequest {
+  SimpleMessage simple_msg = 1;
+};
+
+message SimpleMessageResponse {
+  bool understood = 1;
+};
+
+service SimpleMessageService {
+  rpc Tell(SimpleMessageRequest) returns (SimpleMessageResponse);
+};