Introduce FakeImage class

Introduce FakeImage to improve the current image unittest framework
with following two advantages:
1. generate more than one faking images
2. all faking images generated by random

Change-Id: Ide326fa2a047ddeea478bef97000083617a0b744
Implements: blueprint improve-image-unittest-framework

openstackclient/tests/image/v2/fakes.py

@@ -15,7 +15,10 @@
 
 import copy
 import mock
+import random
+import uuid
 
+from openstackclient.common import utils as common_utils
 from openstackclient.tests import fakes
 from openstackclient.tests import utils
 
@@ -167,3 +170,133 @@ class TestImagev2(utils.TestCommand):
             endpoint=fakes.AUTH_URL,
             token=fakes.AUTH_TOKEN,
         )
+
+
+class FakeImage(object):
+    """Fake one or more images.
+
+    TODO(xiexs): Currently, only image API v2 is supported by this class.
+    """
+
+    @staticmethod
+    def create_one_image(attrs={}):
+        """Create a fake image.
+
+        :param Dictionary attrs:
+            A dictionary with all attrbutes of image
+        :retrun:
+            A FakeResource object with id, name, owner, protected,
+            visibility and tags attrs
+        """
+        # Set default attribute
+        image_info = {
+            'id': 'image-id' + uuid.uuid4().hex,
+            'name': 'image-name' + uuid.uuid4().hex,
+            'owner': 'image-owner' + uuid.uuid4().hex,
+            'protected': bool(random.choice([0, 1])),
+            'visibility': random.choice(['public', 'private']),
+            'tags': [uuid.uuid4().hex for r in range(random.randint(1, 5))],
+        }
+
+        # Overwrite default attributes if there are some attributes set
+        image_info.update(attrs)
+
+        image = fakes.FakeResource(
+            None,
+            image_info,
+            loaded=True)
+        return image
+
+    @staticmethod
+    def create_images(attrs={}, count=2):
+        """Create multiple fake images.
+
+        :param Dictionary attrs:
+            A dictionary with all attributes of image
+        :param Integer count:
+            The number of images to be faked
+        :return:
+            A list of FakeResource objects
+        """
+        images = []
+        for n in range(0, count):
+            images.append(FakeImage.create_one_image(attrs))
+
+        return images
+
+    @staticmethod
+    def get_images(images=None, count=2):
+        """Get an iterable MagicMock object with a list of faked images.
+
+        If images list is provided, then initialize the Mock object with the
+        list. Otherwise create one.
+
+        :param List images:
+            A list of FakeResource objects faking images
+        :param Integer count:
+            The number of images to be faked
+        :return
+            An iterable Mock object with side_effect set to a list of faked
+            images
+        """
+        if images is None:
+            images = FakeImage.create_images(count)
+
+        return mock.MagicMock(side_effect=images)
+
+    @staticmethod
+    def get_image_info(image=None):
+        """Get the image info from a faked image object.
+
+        :param image:
+            A FakeResource objects faking image
+        :return
+            A dictionary which includes the faked image info as follows:
+            {
+                'id': image_id,
+                'name': image_name,
+                'owner': image_owner,
+                'protected': image_protected,
+                'visibility': image_visibility,
+                'tags': image_tags
+            }
+        """
+        if image is not None:
+            return image._info
+        return {}
+
+    @staticmethod
+    def get_image_columns(image=None):
+        """Get the image columns from a faked image object.
+
+        :param image:
+            A FakeResource objects faking image
+        :return
+            A tuple which may include the following keys:
+            ('id', 'name', 'owner', 'protected', 'visibility', 'tags')
+        """
+        if image is not None:
+            return tuple(k for k in sorted(
+                FakeImage.get_image_info(image).keys()))
+        return tuple([])
+
+    @staticmethod
+    def get_image_data(image=None):
+        """Get the image data from a faked image object.
+
+        :param image:
+            A FakeResource objects faking image
+        :return
+            A tuple which may include the following values:
+            ('image-123', 'image-foo', 'admin', False, 'public', 'bar, baz')
+        """
+        data_list = []
+        if image is not None:
+            for x in sorted(FakeImage.get_image_info(image).keys()):
+                if x == 'tags':
+                    # The 'tags' should be format_list
+                    data_list.append(
+                        common_utils.format_list(getattr(image, x)))
+                else:
+                    data_list.append(getattr(image, x))
+        return tuple(data_list)