1 files changed, 32 insertions, 1 deletions
diff --git a/src/python/grpcio_testing/setup.py b/src/python/grpcio_testing/setup.py
index 6ceb1fc5c9..18db71e0f0 100644
--- a/src/python/grpcio_testing/setup.py
+++ b/src/python/grpcio_testing/setup.py
@@ -24,6 +24,23 @@ os.chdir(os.path.dirname(os.path.abspath(__file__)))
 # Break import style to ensure that we can find same-directory modules.
 import grpc_version
 
+
+class _NoOpCommand(setuptools.Command):
+    """No-op command."""
+
+    description = ''
+    user_options = []
+
+    def initialize_options(self):
+        pass
+
+    def finalize_options(self):
+        pass
+
+    def run(self):
+        pass
+
+
 PACKAGE_DIRECTORIES = {
     '': '.',
 }
@@ -33,6 +50,19 @@ INSTALL_REQUIRES = (
     'grpcio>={version}'.format(version=grpc_version.VERSION),
 )
 
+try:
+    import testing_commands as _testing_commands
+    # we are in the build environment, otherwise the above import fails
+    COMMAND_CLASS = {
+        # Run preprocess from the repository *before* doing any packaging!
+        'preprocess': _testing_commands.Preprocess,
+    }
+except ImportError:
+    COMMAND_CLASS = {
+        # wire up commands to no-op not to break the external dependencies
+        'preprocess': _NoOpCommand,
+    }
+
 setuptools.setup(
     name='grpcio-testing',
     version=grpc_version.VERSION,
@@ -43,4 +73,5 @@ setuptools.setup(
     url='https://grpc.io',
     package_dir=PACKAGE_DIRECTORIES,
     packages=setuptools.find_packages('.'),
-    install_requires=INSTALL_REQUIRES)
+    install_requires=INSTALL_REQUIRES,
+    cmdclass=COMMAND_CLASS)