Python Streaming Test Fix (Azure#953)

* Debugging test failure

* testing without header

* Adding header back again

AutoRest/Generators/Python/Python.Tests/AcceptanceTests/file_tests.py

@@ -60,8 +60,8 @@ def test_callback(data, response, progress=[0]):
             self.assertTrue(len(data) > 0)
             self.assertIsNotNone(response)
             self.assertFalse(response._content_consumed)
-            total = float(response.headers.get('Content-Length', 0))
-            if total:
+            total = float(response.headers['Content-Length'])
+            if total < 4096:
                 progress[0] += len(data)
                 print("Downloading... {}%".format(int(progress[0]*100/total)))
 
@@ -94,7 +94,11 @@ def test_callback(data, response, progress=[0]):
 
             self.assertEqual(file_length, 0)
 
+        def add_headers(adapter, request, response, *args, **kwargs):
+            response.headers['Content-Length'] = str(3000 * 1024 * 1024)
+
         file_length = 0
+        client._client.add_hook('response', add_headers)
         stream = client.files.get_file_large(callback=test_callback)
         for data in stream:
             file_length += len(data)

ClientRuntimes/Python/msrest/msrest/service_client.py

@@ -230,6 +230,8 @@ def stream_download(self, data, callback):
                 if callback and callable(callback):
                     callback(chunk, response=data)
                 yield chunk
+        data.close()
+        self._adapter.close()
 
     def stream_upload(self, data, callback):
         """Generator for streaming request body data.