Change the image download to download to tmpdir as a default

This is to prevent (as far as possible) putting the image into the
module under test.

unit_tests/utilities/test_zaza_utilities_openstack.py

@@ -434,16 +434,38 @@ class TestOpenStackUtils(ut_utils.BaseTestCase):
                 expected_status='active',
                 msg='Image status wait')
 
-    def test_create_image(self):
+    def test_create_image_use_tempdir(self):
         glance_mock = mock.MagicMock()
         self.patch_object(openstack_utils.os.path, "exists")
         self.patch_object(openstack_utils, "download_image")
         self.patch_object(openstack_utils, "upload_image_to_glance")
+        self.patch_object(openstack_utils.tempfile, "gettempdir")
+        self.gettempdir.return_value = "wibbly"
         openstack_utils.create_image(
             glance_mock,
             'http://cirros/c.img',
             'bob')
         self.exists.return_value = False
+        self.download_image.assert_called_once_with(
+            'http://cirros/c.img',
+            'wibbly/c.img')
+        self.upload_image_to_glance.assert_called_once_with(
+            glance_mock,
+            'wibbly/c.img',
+            'bob')
+
+    def test_create_image_pass_directory(self):
+        glance_mock = mock.MagicMock()
+        self.patch_object(openstack_utils.os.path, "exists")
+        self.patch_object(openstack_utils, "download_image")
+        self.patch_object(openstack_utils, "upload_image_to_glance")
+        self.patch_object(openstack_utils.tempfile, "gettempdir")
+        openstack_utils.create_image(
+            glance_mock,
+            'http://cirros/c.img',
+            'bob',
+            'tests')
+        self.exists.return_value = False
         self.download_image.assert_called_once_with(
             'http://cirros/c.img',
             'tests/c.img')
@@ -451,6 +473,7 @@ class TestOpenStackUtils(ut_utils.BaseTestCase):
             glance_mock,
             'tests/c.img',
             'bob')
+        self.gettempdir.assert_not_called()
 
     def test_create_ssh_key(self):
         nova_mock = mock.MagicMock()

zaza/utilities/openstack.py

@@ -46,6 +46,7 @@ import re
 import six
 import subprocess
 import sys
+import tempfile
 import tenacity
 import urllib
 
@@ -1536,7 +1537,7 @@ def upload_image_to_glance(glance, local_path, image_name, disk_format='qcow2',
     return image
 
 
-def create_image(glance, image_url, image_name, image_cache_dir='tests'):
+def create_image(glance, image_url, image_name, image_cache_dir=None):
     """Download the image and upload it to glance.
 
     Download an image from image_url and upload it to glance labelling
@@ -1548,11 +1549,15 @@ def create_image(glance, image_url, image_name, image_cache_dir='tests'):
     :type image_url: str
     :param image_name: display name for new image
     :type image_name: str
-    :param image_cache_dir: Directory to store image in before uploading
-    :type image_cache_dir: str
+    :param image_cache_dir: Directory to store image in before uploading. If it
+        is not passed, or is None, then a tmp directory is used.
+    :type image_cache_dir: Option[str, None]
     :returns: glance image pointer
     :rtype: glanceclient.common.utils.RequestIdProxy
     """
+    if image_cache_dir is None:
+        image_cache_dir = tempfile.gettempdir()
+
     logging.debug('Creating glance cirros image '
                   '({})...'.format(image_name))