Use mocks, and breakout tests.

Author: daspecster

vision/google/cloud/vision/_gax.py

@@ -28,22 +28,41 @@ class _GAPICVisionAPI(object):
     """
     def __init__(self, client=None):
         self._client = client
-        self._api = image_annotator_client.ImageAnnotatorClient
+        self._api = image_annotator_client.ImageAnnotatorClient()
 
 
 def _to_gapic_feature(feature):
-    """Helper function to convert a ``Feature`` to a gRPC ``Feature``."""
-    feature_pb = image_annotator_pb2.Feature
-    feature_type = getattr(feature_pb, feature.feature_type)
-    return feature_pb(type=feature_type, max_results=feature.max_results)
+    """Helper function to convert a ``Feature`` to a gRPC ``Feature``.
+
+    :type feature: :class:`~google.cloud.vision.feature.Feature`
+    :param feature: Local ``Feature`` class to be converted to gRPC ``Feature``
+                    instance.
+
+    :rtype: :class:`~google.cloud.grpc.vision.v1.image_annotator_pb2.Feature`
+    :returns: gRPC ``Feature`` converted from
+              :class:`~google.cloud.vision.feature.Feature`.
+    """
+    return image_annotator_pb2.Feature(
+        type=getattr(image_annotator_pb2.Feature, feature.feature_type),
+        max_results=feature.max_results)
 
 
 def _to_gapic_image(image):
-    """Helper function to convert an ``Image`` to a gRPC ``Image``."""
-    image_pb = image_annotator_pb2.Image
+    """Helper function to convert an ``Image`` to a gRPC ``Image``.
+
+    :type image: :class:`~google.cloud.vision.image.Image`
+    :param image: Local ``Image`` class to be converted to gRPC ``Image``.
+
+    :rtype: :class:`~google.cloud.grpc.vision.v1.image_annotator_pb2.Image`
+    :returns: gRPC ``Image`` converted from
+              :class:`~google.cloud.vision.image.Image`.
+    """
     if image.content is not None:
-        return image_pb(content=_to_bytes(image.content))
+        return image_annotator_pb2.Image(content=_to_bytes(image.content))
     if image.source is not None:
-        image_source_pb = image_annotator_pb2.ImageSource
-        image_source = image_source_pb(gcs_image_uri=image.source)
-        return image_pb(source=image_source)
+        return image_annotator_pb2.Image(
+            source=image_annotator_pb2.ImageSource(
+                gcs_image_uri=image.source
+            ),
+        )
+    raise ValueError('No image content or source found.')

vision/unit_tests/test__gax.py

@@ -14,6 +14,13 @@
 
 import unittest
 
+import mock
+
+
+def _make_credentials():
+    import google.auth.credentials
+    return mock.Mock(spec=google.auth.credentials.Credentials)
+
 
 class TestGAXClient(unittest.TestCase):
     def _get_target_class(self):
@@ -26,60 +33,61 @@ def _make_one(self, *args, **kwargs):
     def test_ctor(self):
         from google.cloud.gapic.vision.v1 import image_annotator_client
 
-        client = object()
+        client = mock.Mock(credentials=_make_credentials())
         api = self._make_one(client)
-        self.assertEqual(api._client, client)
-        self.assertIsInstance(api._api(),
+        self.assertIs(api._client, client)
+        self.assertIsInstance(api._api,
                               image_annotator_client.ImageAnnotatorClient)
 
-    def test__to_gapic_feature(self):
+
+class TestToGAPICFeature(unittest.TestCase):
+    def _call_fut(self, feature):
         from google.cloud.vision._gax import _to_gapic_feature
+        return _to_gapic_feature(feature)
+
+    def test__to_gapic_feature(self):
         from google.cloud.vision.feature import Feature
         from google.cloud.vision.feature import FeatureTypes
         from google.cloud.grpc.vision.v1 import image_annotator_pb2
 
         feature = Feature(FeatureTypes.LABEL_DETECTION, 5)
-        feature_pb = _to_gapic_feature(feature)
+        feature_pb = self._call_fut(feature)
         self.assertIsInstance(feature_pb, image_annotator_pb2.Feature)
         self.assertEqual(feature_pb.type, 4)
         self.assertEqual(feature_pb.max_results, 5)
 
+
+class TestToGAPICImage(unittest.TestCase):
+    def _call_fut(self, image):
+        from google.cloud.vision._gax import _to_gapic_image
+        return _to_gapic_image(image)
+
     def test__to_gapic_image_content(self):
         import base64
-        from google.cloud.vision._gax import _to_gapic_image
         from google.cloud.vision.image import Image
         from google.cloud.grpc.vision.v1 import image_annotator_pb2
 
         image_content = b'abc 1 2 3'
         b64_content = base64.b64encode(image_content)
         client = object()
         image = Image(client, content=image_content)
-        image_pb = _to_gapic_image(image)
+        image_pb = self._call_fut(image)
         self.assertIsInstance(image_pb, image_annotator_pb2.Image)
         self.assertEqual(image_pb.content, b64_content)
 
     def test__to_gapic_image_uri(self):
-        from google.cloud.vision._gax import _to_gapic_image
         from google.cloud.vision.image import Image
         from google.cloud.grpc.vision.v1 import image_annotator_pb2
 
         image_uri = b'gs://1234/34.jpg'
         client = object()
         image = Image(client, source_uri=image_uri)
-        image_pb = _to_gapic_image(image)
+        image_pb = self._call_fut(image)
         self.assertIsInstance(image_pb, image_annotator_pb2.Image)
         self.assertEqual(image_pb.source.gcs_image_uri, image_uri)
 
-    def test__to_gapic_image(self):
-        from google.cloud.vision._gax import _to_gapic_image
-
-        class MockImage(object):
-            @property
-            def content(self):
-                return None
-
-            @property
-            def source(self):
-                return None
-        image = MockImage()
-        self.assertIsNone(_to_gapic_image(image))
+    def test__to_gapic_with_empty_image(self):
+        image = mock.Mock(
+            content=None, source=None, spec=['content', 'source'])
+        with self.assertRaises(ValueError):
+            self._call_fut(image)

vision/unit_tests/test_client.py

@@ -55,7 +55,7 @@ def test_annotate_with_preset_api(self):
         client._vision_api.annotate()
         api.annotate.assert_called_once_with()
 
-    def test_annotate_with_gax(self):
+    def test_make_gax_client(self):
         from google.cloud.vision._gax import _GAPICVisionAPI
 
         credentials = _make_credentials()
@@ -64,7 +64,7 @@ def test_annotate_with_gax(self):
         client._connection = _Connection()
         self.assertIsInstance(client._vision_api, _GAPICVisionAPI)
 
-    def test_annotate_with_http(self):
+    def test_make_http_client(self):
         from google.cloud.vision._http import _HTTPVisionAPI
 
         credentials = _make_credentials()