Fixed nested namespace library import issue (#492)

Author: Hazhzeng

azure/functions_worker/dispatcher.py

@@ -10,6 +10,7 @@
 import threading
 import os
 import sys
+import importlib
 
 import grpc
 import pkg_resources
@@ -374,6 +375,9 @@ async def _handle__function_environment_reload_request(self, req):
             for var in env_vars:
                 os.environ[var] = env_vars[var]
 
+            # Reload azure namespace for customer's libraries
+            importlib.reload(sys.modules['azure'])
+
             success_response = protos.FunctionEnvironmentReloadResponse(
                 result=protos.StatusResult(
                     status=protos.StatusResult.Success))

tests/unittests/azure_namespace_import/azure_namespace_import.py

@@ -0,0 +1,53 @@
+import os
+import sys
+import shutil
+import asyncio
+
+from azure.functions_worker import protos
+from azure.functions_worker import testutils
+
+
+async def vertify_nested_namespace_import():
+    test_env = {}
+    request = protos.FunctionEnvironmentReloadRequest(
+        environment_variables=test_env)
+
+    request_msg = protos.StreamingMessage(
+        request_id='0',
+        function_environment_reload_request=request)
+
+    disp = testutils.create_dummy_dispatcher()
+
+    # Mock intepreter starts in placeholder mode
+    import azure.module_a as mod_a  # noqa: F401
+
+    # Mock function specialization, load customer's libraries and functionapps
+    ns_root = os.path.join(
+        testutils.UNIT_TESTS_ROOT,
+        'azure_namespace_import',
+        'namespace_location_b')
+    test_path = os.path.join(ns_root, 'azure', 'namespace_b', 'module_b')
+    test_mod_path = os.path.join(test_path, 'test_module.py')
+
+    os.makedirs(test_path)
+    with open(test_mod_path, 'w') as f:
+        f.write('MESSAGE = "module_b is imported"')
+
+    try:
+        # Mock a customer uses test_module
+        if sys.argv[1].lower() == 'true':
+            await disp._handle__function_environment_reload_request(
+                request_msg)
+        from azure.namespace_b.module_b import test_module
+        print(test_module.MESSAGE)
+    except ModuleNotFoundError:
+        print('module_b fails to import')
+    finally:
+        # Cleanup
+        shutil.rmtree(ns_root)
+
+
+if __name__ == '__main__':
+    loop = asyncio.get_event_loop()
+    loop.run_until_complete(vertify_nested_namespace_import())
+    loop.close()

tests/unittests/azure_namespace_import/namespace_location_a/azure/module_a/__init__.py

@@ -0,0 +1 @@
+MESSAGE = "module_a is imported"

tests/unittests/azure_namespace_import/test_azure_namespace_import.sh

@@ -0,0 +1,10 @@
+#! /bin/bash
+
+# $1 controls whether we allow reload module ("true" or "false")
+
+SCRIPT_DIR="$(dirname $0)"
+export PYTHONPATH="$SCRIPT_DIR/namespace_location_a:$SCRIPT_DIR/namespace_location_b"
+
+python $SCRIPT_DIR/azure_namespace_import.py $1
+
+unset PYTHONPATH

tests/unittests/test_rpc_messages.py

@@ -69,3 +69,30 @@ def test_successful_sys_path_import(self):
         self._verify_sys_path_import(
             'success',
             'This module was imported!')
+
+    def _verify_azure_namespace_import(self, result, expected_output):
+        try:
+            path_import_script = os.path.join(
+                testutils.UNIT_TESTS_ROOT,
+                'azure_namespace_import',
+                'test_azure_namespace_import.sh')
+
+            subprocess.run(['chmod +x ' + path_import_script], shell=True)
+
+            output = subprocess.check_output(
+                [path_import_script, result],
+                stderr=subprocess.STDOUT)
+            decoded_output = output.decode(sys.stdout.encoding).strip()
+            self.assertTrue(expected_output in decoded_output)
+        finally:
+            self._reset_environ()
+
+    def test_failed_azure_namespace_import(self):
+        self._verify_azure_namespace_import(
+            'false',
+            'module_b fails to import')
+
+    def test_successful_azure_namespace_import(self):
+        self._verify_azure_namespace_import(
+            'true',
+            'module_b is imported')