Fix web-download fails with default node_staging_uri

Web-download import method fails to import image to backend if
'node_staging_uri' is not set in glance-api.conf (or when the value
ends with a '/', as the default setting does) due to "local variable
'separator' referenced before assignment" error.

Co-authored-by: Abhishek Kekane <akekane@redhat.com>
Co-authored-by: Brian Rosmaita <rosmaita.fossdev@gmail.com>

Change-Id: I056fb7a1f7a7ef6bc14ea54133cf083b2b9d9920
Closes-Bug: #1753964
(cherry picked from commit ff1ba4f3f5)

glance/async/flows/api_image_import.py

@@ -307,10 +307,11 @@ def get_flow(**kwargs):
     import_method = kwargs.get('import_req')['method']['name']
     uri = kwargs.get('import_req')['method'].get('uri')
 
+    separator = ''
+    if not CONF.node_staging_uri.endswith('/'):
+        separator = '/'
+
     if not uri and import_method == 'glance-direct':
-        separator = ''
-        if not CONF.node_staging_uri.endswith('/'):
-            separator = '/'
         uri = separator.join((CONF.node_staging_uri, str(image_id)))
 
     flow = lf.Flow(task_type, retry=retry.AlwaysRevert())
@@ -318,8 +319,6 @@ def get_flow(**kwargs):
     if import_method == 'web-download':
         downloadToStaging = internal_plugins.get_import_plugin(**kwargs)
         flow.add(downloadToStaging)
-        if not CONF.node_staging_uri.endswith('/'):
-            separator = '/'
         file_uri = separator.join((CONF.node_staging_uri, str(image_id)))
     else:
         file_uri = uri

glance/tests/unit/async/flows/test_api_image_import.py

@@ -0,0 +1,90 @@
+# Copyright 2018 Verizon Wireless
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import mock
+
+from oslo_config import cfg
+
+import glance.async.flows.api_image_import as import_flow
+import glance.tests.utils as test_utils
+
+CONF = cfg.CONF
+
+TASK_TYPE = 'api_image_import'
+TASK_ID1 = 'dbbe7231-020f-4311-87e1-5aaa6da56c02'
+IMAGE_ID1 = '41f5b3b0-f54c-4cef-bd45-ce3e376a142f'
+
+
+class TestApiImageImportTask(test_utils.BaseTestCase):
+
+    def setUp(self):
+        super(TestApiImageImportTask, self).setUp()
+
+        self.wd_task_input = {
+            "import_req": {
+                "method": {
+                    "name": "web-download",
+                    "uri": "http://example.com/image.browncow"
+                }
+            }
+        }
+
+        self.gd_task_input = {
+            "import_req": {
+                "method": {
+                    "name": "glance-direct"
+                }
+            }
+        }
+
+        self.mock_task_repo = mock.MagicMock()
+        self.mock_image_repo = mock.MagicMock()
+
+    @mock.patch('glance.async.flows.api_image_import._VerifyStaging.__init__')
+    @mock.patch('taskflow.patterns.linear_flow.Flow.add')
+    @mock.patch('taskflow.patterns.linear_flow.__init__')
+    def _pass_uri(self, mock_lf_init, mock_flow_add, mock_VS_init,
+                  uri, file_uri, import_req):
+        flow_kwargs = {"task_id": TASK_ID1,
+                       "task_type": TASK_TYPE,
+                       "task_repo": self.mock_task_repo,
+                       "image_repo": self.mock_image_repo,
+                       "image_id": IMAGE_ID1,
+                       "import_req": import_req}
+
+        mock_lf_init.return_value = None
+        mock_VS_init.return_value = None
+
+        self.config(node_staging_uri=uri)
+        import_flow.get_flow(**flow_kwargs)
+        mock_VS_init.assert_called_with(TASK_ID1, TASK_TYPE,
+                                        self.mock_task_repo,
+                                        file_uri)
+
+    def test_get_flow_handles_node_uri_with_ending_slash(self):
+        test_uri = 'file:///some/where/'
+        expected_uri = '{0}{1}'.format(test_uri, IMAGE_ID1)
+        self._pass_uri(uri=test_uri, file_uri=expected_uri,
+                       import_req=self.gd_task_input['import_req'])
+        self._pass_uri(uri=test_uri, file_uri=expected_uri,
+                       import_req=self.wd_task_input['import_req'])
+
+    def test_get_flow_handles_node_uri_without_ending_slash(self):
+        test_uri = 'file:///some/where'
+        expected_uri = '{0}/{1}'.format(test_uri, IMAGE_ID1)
+        self._pass_uri(uri=test_uri, file_uri=expected_uri,
+                       import_req=self.wd_task_input['import_req'])
+        self._pass_uri(uri=test_uri, file_uri=expected_uri,
+                       import_req=self.gd_task_input['import_req'])