Fix bazel grpc_tools test

tools/distrib/python/grpcio_tools/grpc_tools/protoc.py

@@ -24,6 +24,8 @@ from grpc_tools import _protoc_compiler
 _PROTO_MODULE_SUFFIX = "_pb2"
 _SERVICE_MODULE_SUFFIX = "_pb2_grpc"
 
+_DISABLE_DYNAMIC_STUBS = "GRPC_PYTHON_DISABLE_DYNAMIC_STUBS"
+
 
 def main(command_arguments):
     """Run the protocol buffer compiler with the given command-line arguments.
@@ -42,6 +44,21 @@ if sys.version_info[0] > 2:
     import importlib.machinery
     import threading
 
+    _FINDERS_INSTALLED = False
+    _FINDERS_INSTALLED_LOCK = threading.Lock()
+
+    def _maybe_install_proto_finders():
+        global _FINDERS_INSTALLED
+        with _FINDERS_INSTALLED_LOCK:
+            if not _FINDERS_INSTALLED:
+                sys.meta_path.extend([
+                    ProtoFinder(_PROTO_MODULE_SUFFIX,
+                                _protoc_compiler.get_protos),
+                    ProtoFinder(_SERVICE_MODULE_SUFFIX,
+                                _protoc_compiler.get_services)
+                ])
+                _FINDERS_INSTALLED = True
+
     def _module_name_to_proto_file(suffix, module_name):
         components = module_name.split(".")
         proto_name = components[-1][:-1 * len(suffix)]
@@ -54,6 +71,7 @@ if sys.version_info[0] > 2:
 
     def _protos(protobuf_path):
         """Returns a gRPC module generated from the indicated proto file."""
+        _maybe_install_proto_finders()
         module_name = _proto_file_to_module_name(_PROTO_MODULE_SUFFIX,
                                                  protobuf_path)
         module = importlib.import_module(module_name)
@@ -61,6 +79,7 @@ if sys.version_info[0] > 2:
 
     def _services(protobuf_path):
         """Returns a module generated from the indicated proto file."""
+        _maybe_install_proto_finders()
         _protos(protobuf_path)
         module_name = _proto_file_to_module_name(_SERVICE_MODULE_SUFFIX,
                                                  protobuf_path)
@@ -137,10 +156,10 @@ if sys.version_info[0] > 2:
                         ProtoLoader(self._suffix, self._codegen_fn, fullname,
                                     filepath, search_path))
 
-    sys.meta_path.extend([
+    # NOTE(rbellevi): We provide an environment variable that enables users to completely
-        ProtoFinder(_PROTO_MODULE_SUFFIX, _protoc_compiler.get_protos),
+    # disable this behavior if it is not desired, e.g. for performance reasons.
-        ProtoFinder(_SERVICE_MODULE_SUFFIX, _protoc_compiler.get_services)
+    if not os.getenv(_DISABLE_DYNAMIC_STUBS):
-    ])
+        _maybe_install_proto_finders()
 
 if __name__ == '__main__':
     proto_include = pkg_resources.resource_filename('grpc_tools', '_proto')

tools/distrib/python/grpcio_tools/grpc_tools/test/BUILD.bazel

@@ -6,14 +6,14 @@ proto_library(
     name = "simplest_proto",
     testonly = True,
     srcs = ["simplest.proto"],
-    strip_import_prefix = "/tools/distrib/python/grpcio_tools/",
+    strip_import_prefix = "/tools/distrib/python/grpcio_tools/grpc_tools/test/",
 )
 
 proto_library(
     name = "complicated_proto",
     testonly = True,
     srcs = ["complicated.proto"],
-    strip_import_prefix = "/tools/distrib/python/grpcio_tools/",
+    strip_import_prefix = "/tools/distrib/python/grpcio_tools/grpc_tools/test/",
     deps = [":simplest_proto"],
 )
 

tools/distrib/python/grpcio_tools/grpc_tools/test/complicated.proto

@@ -1,12 +1,12 @@
 syntax = "proto3";
 
-package grpc_tools.test.complicated;
+package test.complicated;
 
-import "grpc_tools/test/simplest.proto";
+import "simplest.proto";
 
 message ComplicatedMessage {
   bool yes = 1;
   bool no = 2;
   bool why = 3;
-  grpc_tools.test.simplest.SimplestMessage simplest_message = 4;
+  simplest.SimplestMessage simplest_message = 4;
 };

tools/distrib/python/grpcio_tools/grpc_tools/test/protoc_test.py

@@ -40,7 +40,7 @@ def _run_in_subprocess(test_case):
 def _augmented_syspath(new_paths):
     original_sys_path = sys.path
     if new_paths is not None:
-        sys.path = sys.path + list(new_paths)
+        sys.path = list(new_paths) + sys.path
     try:
         yield
     finally:
@@ -49,31 +49,36 @@ def _augmented_syspath(new_paths):
 
 def _test_import_protos():
     from grpc_tools import protoc
-    with _augmented_syspath(("tools/distrib/python/grpcio_tools/",)):
+    with _augmented_syspath(
-        protos = protoc._protos("grpc_tools/test/simple.proto")
+        ("tools/distrib/python/grpcio_tools/grpc_tools/test/",)):
+        protos = protoc._protos("simple.proto")
         assert protos.SimpleMessage is not None
 
 
 def _test_import_services():
     from grpc_tools import protoc
-    with _augmented_syspath(("tools/distrib/python/grpcio_tools/",)):
+    with _augmented_syspath(
-        protos = protoc._protos("grpc_tools/test/simple.proto")
+        ("tools/distrib/python/grpcio_tools/grpc_tools/test/",)):
-        services = protoc._services("grpc_tools/test/simple.proto")
+        protos = protoc._protos("simple.proto")
+        services = protoc._services("simple.proto")
         assert services.SimpleMessageServiceStub is not None
 
 
 def _test_import_services_without_protos():
     from grpc_tools import protoc
-    services = protoc._services("grpc_tools/test/simple.proto")
+    with _augmented_syspath(
-    assert services.SimpleMessageServiceStub is not None
+        ("tools/distrib/python/grpcio_tools/grpc_tools/test/",)):
+        services = protoc._services("simple.proto")
+        assert services.SimpleMessageServiceStub is not None
 
 
 def _test_proto_module_imported_once():
     from grpc_tools import protoc
-    with _augmented_syspath(("tools/distrib/python/grpcio_tools/",)):
+    with _augmented_syspath(
-        protos = protoc._protos("grpc_tools/test/simple.proto")
+        ("tools/distrib/python/grpcio_tools/grpc_tools/test/",)):
-        services = protoc._services("grpc_tools/test/simple.proto")
+        protos = protoc._protos("simple.proto")
-        complicated_protos = protoc._protos("grpc_tools/test/complicated.proto")
+        services = protoc._services("simple.proto")
+        complicated_protos = protoc._protos("complicated.proto")
         simple_message = protos.SimpleMessage()
         complicated_message = complicated_protos.ComplicatedMessage()
         assert (simple_message.simpler_message.simplest_message.__class__ is
@@ -81,10 +86,11 @@ def _test_proto_module_imported_once():
 
 
 def _test_static_dynamic_combo():
-    from grpc_tools.test import complicated_pb2
+    with _augmented_syspath(
-    from grpc_tools import protoc
+        ("tools/distrib/python/grpcio_tools/grpc_tools/test/",)):
-    with _augmented_syspath(("tools/distrib/python/grpcio_tools/",)):
+        from grpc_tools import protoc
-        protos = protoc._protos("grpc_tools/test/simple.proto")
+        import complicated_pb2
+        protos = protoc._protos("simple.proto")
         static_message = complicated_pb2.ComplicatedMessage()
         dynamic_message = protos.SimpleMessage()
         assert (dynamic_message.simpler_message.simplest_message.__class__ is
@@ -93,8 +99,7 @@ def _test_static_dynamic_combo():
 
 def _test_combined_import():
     from grpc_tools import protoc
-    protos, services = protoc._protos_and_services(
+    protos, services = protoc._protos_and_services("simple.proto")
-        "grpc_tools/test/simple.proto")
     assert protos.SimpleMessage is not None
     assert services.SimpleMessageServiceStub is not None
 
@@ -102,7 +107,7 @@ def _test_combined_import():
 def _test_syntax_errors():
     from grpc_tools import protoc
     try:
-        protos = protoc._protos("grpc_tools/test/flawed.proto")
+        protos = protoc._protos("flawed.proto")
     except Exception as e:
         error_str = str(e)
         assert "flawed.proto" in error_str

tools/distrib/python/grpcio_tools/grpc_tools/test/simple.proto

@@ -1,8 +1,8 @@
 syntax = "proto3";
 
-package grpc_tools.test.simple;
+package simple;
 
-import "grpc_tools/test/simpler.proto";
+import "simpler.proto";
 
 message SimpleMessage {
   string msg = 1;
@@ -10,7 +10,7 @@ message SimpleMessage {
     bool personal = 2;
     bool business = 3;
   };
-  grpc_tools.test.simpler.SimplerMessage simpler_message = 4;
+  simpler.SimplerMessage simpler_message = 4;
 };
 
 message SimpleMessageRequest {

tools/distrib/python/grpcio_tools/grpc_tools/test/simpler.proto

@@ -1,11 +1,11 @@
 syntax = "proto3";
 
-package grpc_tools.test.simpler;
+package simpler;
 
-import "grpc_tools/test/simplest.proto";
+import "simplest.proto";
 
 message SimplerMessage {
   int64 do_i_even_exist = 1;
-  grpc_tools.test.simplest.SimplestMessage simplest_message = 2;
+  simplest.SimplestMessage simplest_message = 2;
 };
 

tools/distrib/python/grpcio_tools/grpc_tools/test/simplest.proto

@@ -1,6 +1,6 @@
 syntax = "proto3";
 
-package grpc_tools.test.simplest;
+package simplest;
 
 message SimplestMessage {
   int64 i_definitely_dont_exist = 1;