[QUEENS Only] Always do a image pull

In queens we use paunch to manage the images and containers. Container
images are not updated if the image has changed but the container tag
has not because we simply check if the container exists on disk. This
change drops the exists check and just issues a pull for all containers
to ensure they are up to date. In newer versions we always pre-fetch the
containers as part of the deployment so we don't need to do this
image management in paunch (or ansible).

Change-Id: Icb5b949c0d9cd41328e1af3d4ec3066d6971c6fd
Closes-Bug: #1895974

paunch/builder/compose1.py

@@ -290,10 +290,6 @@ class ComposeV1Builder(object):
 
         for image in sorted(images):
 
-            # only pull if the image does not exist locally
-            if self.runner.inspect(image, format='exists', type='image'):
-                continue
-
             try:
                 (cmd_stdout, cmd_stderr) = self._pull(image)
             except PullException as e:

paunch/tests/test_builder_compose1.py

@@ -58,8 +58,7 @@ class TestComposeV1Builder(base.TestCase):
         r = runner.DockerRunner(managed_by='tester', docker_cmd='docker')
         exe = mock.Mock()
         exe.side_effect = [
-            ('exists', '', 0),  # inspect for image centos:6
-            ('', '', 1),  # inspect for missing image centos:7
+            ('Pulled centos:6', '', 0),  # inspect for image centos:6
             ('Pulled centos:7', 'ouch', 1),  # pull centos:6 fails
             ('Pulled centos:7', '', 0),  # pull centos:6 succeeds
             # container_names for delete_missing
@@ -94,6 +93,7 @@ three-12345678 three''', '', 0),
         stdout, stderr, deploy_status_code = builder.apply()
         self.assertEqual(0, deploy_status_code)
         self.assertEqual([
+            'Pulled centos:6',
             'Pulled centos:7',
             'Created one-12345678',
             'Created two-12345678',
@@ -103,15 +103,9 @@ three-12345678 three''', '', 0),
         self.assertEqual([], stderr)
 
         exe.assert_has_calls([
-            # inspect existing image centos:6
+            # Pull image centos:6
             mock.call(
-                ['docker', 'inspect', '--type', 'image',
-                 '--format', 'exists', 'centos:6'], mock.ANY
-            ),
-            # inspect and pull missing image centos:7
-            mock.call(
-                ['docker', 'inspect', '--type', 'image',
-                 '--format', 'exists', 'centos:7'], mock.ANY
+                ['docker', 'pull', 'centos:6'], mock.ANY
             ),
             # first pull attempt fails
             mock.call(
@@ -236,7 +230,7 @@ three-12345678 three''', '', 0),
         exe = mock.Mock()
         exe.side_effect = [
             # inspect for image centos:7
-            ('exists', '', 0),
+            ('Pulled centos:7', '', 0),
             # stop five
             ('', '', 0),
             # rm five
@@ -267,6 +261,7 @@ three-12345678 three''', '', 0),
         stdout, stderr, deploy_status_code = builder.apply()
         self.assertEqual(0, deploy_status_code)
         self.assertEqual([
+            'Pulled centos:7',
             'Created two-12345678',
             'Created three-12345678',
             'Created four-12345678',
@@ -275,10 +270,9 @@ three-12345678 three''', '', 0),
         self.assertEqual([], stderr)
 
         exe.assert_has_calls([
-            # inspect image centos:7
+            # pull image centos:7
             mock.call(
-                ['docker', 'inspect', '--type', 'image',
-                 '--format', 'exists', 'centos:7'], mock.ANY
+                ['docker', 'pull', 'centos:7'], mock.ANY
             ),
             # rm containers not in config
             mock.call(['docker', 'stop', 'five'], mock.ANY),
@@ -363,8 +357,7 @@ three-12345678 three''', '', 0),
         r = runner.DockerRunner(managed_by='tester', docker_cmd='docker')
         exe = mock.Mock()
         exe.side_effect = [
-            ('exists', '', 0),  # inspect for image centos:6
-            ('', '', 1),  # inspect for missing image centos:7
+            ('Pulled centos:6', '', 0),  # inspect for image centos:6
             ('Pulling centos:7', 'ouch', 1),  # pull centos:7 failure
             ('Pulling centos:7', 'ouch', 1),  # pull centos:7 retry 2
             ('Pulling centos:7', 'ouch', 1),  # pull centos:7 retry 3
@@ -380,19 +373,12 @@ three-12345678 three''', '', 0),
 
         stdout, stderr, deploy_status_code = builder.apply()
         self.assertEqual(1, deploy_status_code)
-        self.assertEqual(['Pulling centos:7'], stdout)
+        self.assertEqual(['Pulled centos:6', 'Pulling centos:7'], stdout)
         self.assertEqual(['ouch'], stderr)
 
         exe.assert_has_calls([
-            # inspect existing image centos:6
-            mock.call(
-                ['docker', 'inspect', '--type', 'image',
-                 '--format', 'exists', 'centos:6'], mock.ANY
-            ),
-            # inspect and pull missing image centos:7
             mock.call(
-                ['docker', 'inspect', '--type', 'image',
-                 '--format', 'exists', 'centos:7'], mock.ANY
+                ['docker', 'pull', 'centos:6'], mock.ANY
             ),
             mock.call(
                 ['docker', 'pull', 'centos:7'], mock.ANY