Make imports compatible with Grizzly

Change-Id: Ib4f3a3976097ab5977334d1768007668e3953c45

savannadashboard/api/client.py

@@ -1,13 +1,17 @@
 import logging
 
-from horizon.api import base
-
 from savannadashboard.api import cluster_templates
 from savannadashboard.api import clusters
 from savannadashboard.api import httpclient
 from savannadashboard.api import images
 from savannadashboard.api import node_group_templates
 from savannadashboard.api import plugins
+from savannadashboard.utils import importutils
+
+# horizon.api is for backward compatibility with folsom
+base = importutils.import_any('openstack_dashboard.api.base',
+                              'horizon.api.base')
+
 
 LOG = logging.getLogger(__name__)
 

savannadashboard/image_registry/forms.py

@@ -16,12 +16,16 @@
 # limitations under the License.
 
 from django.utils.translation import ugettext_lazy as _
-from horizon import api
 from horizon import exceptions
 from horizon import forms
 import json
 
 from savannadashboard.api import client as savannaclient
+from savannadashboard.utils import importutils
+
+# horizon.api is for backward compatibility with folsom
+glance = importutils.import_any('openstack_dashboard.api.glance',
+                                'horizon.api.glance')
 
 
 class ImageForm(forms.SelfHandlingForm):
@@ -79,7 +83,7 @@ class RegisterImageForm(ImageForm):
         public = {"is_public": True,
                   "status": "active"}
         try:
-            imgs = api.glance.image_list_detailed(request, filters=public)
+            imgs = glance.image_list_detailed(request, filters=public)
             public_images, _more = imgs
         except Exception:
             public_images = []

savannadashboard/nodegroup_templates/tabs.py

@@ -14,14 +14,19 @@
 # implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-from horizon.api import nova
-
-from django.utils.translation import ugettext_lazy as _
 
 import logging
 
+from django.utils.translation import ugettext_lazy as _
 from horizon import tabs
+
 from savannadashboard.api import client as savannaclient
+from savannadashboard.utils import importutils
+
+# horizon.api is for backward compatibility with folsom
+nova = importutils.import_any('openstack_dashboard.api.nova',
+                              'horizon.api.nova')
+
 
 LOG = logging.getLogger(__name__)
 

savannadashboard/nodegroup_templates/workflows.py

@@ -15,7 +15,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from horizon.api import nova
 from horizon import forms
 import logging
 
@@ -27,10 +26,15 @@ from horizon import workflows
 
 from savannadashboard.api import client as savannaclient
 from savannadashboard.api import helpers
+from savannadashboard.utils import importutils
 from savannadashboard.utils import workflow_helpers
 from savannadashboard.utils.workflow_helpers import _create_step_action
 from savannadashboard.utils.workflow_helpers import build_control
 
+# horizon.api is for backward compatibility with folsom
+nova = importutils.import_any('openstack_dashboard.api.nova',
+                              'horizon.api.nova')
+
 
 LOG = logging.getLogger(__name__)
 

savannadashboard/openstack/common/importutils.py

@@ -0,0 +1,68 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2011 OpenStack Foundation.
+# 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 related utilities and helper functions.
+"""
+
+import sys
+import traceback
+
+
+def import_class(import_str):
+    """Returns a class from a string including module and class."""
+    mod_str, _sep, class_str = import_str.rpartition('.')
+    try:
+        __import__(mod_str)
+        return getattr(sys.modules[mod_str], class_str)
+    except (ValueError, AttributeError):
+        raise ImportError('Class %s cannot be found (%s)' %
+                          (class_str,
+                           traceback.format_exception(*sys.exc_info())))
+
+
+def import_object(import_str, *args, **kwargs):
+    """Import a class and return an instance of it."""
+    return import_class(import_str)(*args, **kwargs)
+
+
+def import_object_ns(name_space, import_str, *args, **kwargs):
+    """Tries to import object from default namespace.
+
+    Imports a class and return an instance of it, first by trying
+    to find the class in a default namespace, then failing back to
+    a full path if not found in the default namespace.
+    """
+    import_value = "%s.%s" % (name_space, import_str)
+    try:
+        return import_class(import_value)(*args, **kwargs)
+    except ImportError:
+        return import_class(import_str)(*args, **kwargs)
+
+
+def import_module(import_str):
+    """Import a module."""
+    __import__(import_str)
+    return sys.modules[import_str]
+
+
+def try_import(import_str, default=None):
+    """Try to import a module and if it fails return default."""
+    try:
+        return import_module(import_str)
+    except ImportError:
+        return default

savannadashboard/utils/importutils.py

@@ -0,0 +1,11 @@
+from savannadashboard.openstack.common import importutils
+
+
+def import_any(*args):
+    for module_name in args:
+        module = importutils.try_import(module_name)
+        if module is not None:
+            return module
+
+    raise RuntimeError('Unable to import any modules from the list %s' %
+                       args)