Fix 500 from image-import on queued images

If you run image-import api on any image which is in queued state having
valid container-format and disk-format set will return 500 error as it
raises IOError: [Errno 2] No such file or directory:
'/tmp/staging/567bfb61-d9f7-47e5-aa1a-90b7797e70be'. The reason is image
does not have data stored in staging area.

Restricted transition from queued to importing state and returned HTTP 409
conflict error to the user.

Change-Id: I3d3ab283fd0faf4b63365ff2dbeb714913f02b27
Closes-Bug: #1733813

glance/api/v2/images.py

@@ -107,6 +107,8 @@ class ImagesController(object):
         except exception.Forbidden as e:
             LOG.debug("User not permitted to create image import task.")
             raise webob.exc.HTTPForbidden(explanation=e.msg)
+        except exception.Conflict as e:
+            raise webob.exc.HTTPConflict(explanation=e.msg)
 
         return image_id
 

glance/async/flows/api_image_import.py

@@ -194,7 +194,7 @@ class _ImportToStore(task.Task):
         # implementation
         image = self.image_repo.get(self.image_id)
         image.status = 'importing'
-        self.image_repo.save(image)
+        self.image_repo.save(image, from_state='uploading')
 
         # NOTE(flaper87): Let's dance... and fall
         #

glance/tests/unit/v2/test_images_resource.py

@@ -14,6 +14,7 @@
 #    under the License.
 
 import datetime
+import eventlet
 import uuid
 
 import glance_store as store
@@ -599,6 +600,18 @@ class TestImagesController(base.IsolatedUnitTest):
         self.assertRaises(webob.exc.HTTPNotFound,
                           self.controller.show, request, UUID4)
 
+    def test_image_import_raises_conflict(self):
+        request = unit_test_utils.get_fake_request()
+        # NOTE(abhishekk): Due to
+        # https://bugs.launchpad.net/glance/+bug/1712463 taskflow is not
+        # executing. Once it is fixed instead of mocking spawn_n method
+        # we should mock execute method of _ImportToStore task.
+        with mock.patch.object(eventlet.GreenPool, 'spawn_n',
+                               side_effect=exception.Conflict):
+            self.assertRaises(webob.exc.HTTPConflict,
+                              self.controller.import_image, request, UUID4,
+                              {})
+
     def test_create(self):
         request = unit_test_utils.get_fake_request()
         image = {'name': 'image-1'}