Return Customer's Quota Usage through Admin API

DocImpact: This patch adds an extension 'UsedLimitsForAdmin'. If this
extention is enabled then it extends the used limits API behavior, such
that admin can fetch the details of any customer's quota usage by passing
the customer's tenant id in query parameters.The API signature for the
same is 'v2/{tenant_id}/limits?tenant_id={customer_tenant_id}'

Change-Id: I89b8b5083e46b899458407426c89a3865e960faa
Implements: blueprint customer-quota-through-admin-api

2 files changed, 47 insertions, 3 deletions

diff --git a/nova/api/openstack/compute/contrib/used_limits.py b/nova/api/openstack/compute/contrib/used_limits.py
index e00f0a9eb..5a90a9def 100644
--- a/nova/api/openstack/compute/contrib/used_limits.py
+++ b/nova/api/openstack/compute/contrib/used_limits.py
@@ -26,6 +26,8 @@ QUOTAS = quota.QUOTAS
 XMLNS = "http://docs.openstack.org/compute/ext/used_limits/api/v1.1"
 ALIAS = "os-used-limits"
 authorize = extensions.soft_extension_authorizer('compute', 'used_limits')
+authorize_for_admin = extensions.extension_authorizer('compute',
+                                                      'used_limits_for_admin')
 
 
 class UsedLimitsTemplate(xmlutil.TemplateBuilder):
@@ -37,6 +39,9 @@ class UsedLimitsTemplate(xmlutil.TemplateBuilder):
 
 class UsedLimitsController(wsgi.Controller):
 
+    def __init__(self, ext_mgr):
+        self.ext_mgr = ext_mgr
+
     @staticmethod
     def _reserved(req):
         try:
@@ -48,8 +53,8 @@ class UsedLimitsController(wsgi.Controller):
     def index(self, req, resp_obj):
         resp_obj.attach(xml=UsedLimitsTemplate())
         context = req.environ['nova.context']
-        quotas = QUOTAS.get_project_quotas(context, context.project_id,
-                                           usages=True)
+        project_id = self._project_id(context, req)
+        quotas = QUOTAS.get_project_quotas(context, project_id, usages=True)
         quota_map = {
             'totalRAMUsed': 'ram',
             'totalCoresUsed': 'cores',
@@ -66,6 +71,18 @@ class UsedLimitsController(wsgi.Controller):
 
         resp_obj.obj['limits']['absolute'].update(used_limits)
 
+    def _project_id(self, context, req):
+        if self.ext_mgr.is_loaded('os-used-limits-for-admin'):
+            if 'tenant_id' in req.GET:
+                tenant_id = req.GET.get('tenant_id')
+                target = {
+                    'project_id': tenant_id,
+                    'user_id': context.user_id
+                    }
+                authorize_for_admin(context, target=target)
+                return tenant_id
+        return context.project_id
+
 
 class Used_limits(extensions.ExtensionDescriptor):
     """Provide data on limited resources that are being used."""
@@ -76,7 +93,7 @@ class Used_limits(extensions.ExtensionDescriptor):
     updated = "2012-07-13T00:00:00+00:00"
 
     def get_controller_extensions(self):
-        controller = UsedLimitsController()
+        controller = UsedLimitsController(self.ext_mgr)
         limits_ext = extensions.ControllerExtension(self, 'limits',
                                                     controller=controller)
         return [limits_ext]
diff --git a/nova/api/openstack/compute/contrib/used_limits_for_admin.py b/nova/api/openstack/compute/contrib/used_limits_for_admin.py
new file mode 100644
index 000000000..a6ec9c002
--- /dev/null
+++ b/nova/api/openstack/compute/contrib/used_limits_for_admin.py
@@ -0,0 +1,27 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2013 OpenStack Foundation
+#
+#    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
+
+from nova.api.openstack import extensions
+
+
+class Used_limits_for_admin(extensions.ExtensionDescriptor):
+    """Provide data to admin on limited resources used by other tenants."""
+
+    name = "UsedLimitsForAdmin"
+    alias = "os-used-limits-for-admin"
+    namespace = ("http://docs.openstack.org/compute/ext/used_limits_for_admin"
+                "/api/v1.1")
+    updated = "2013-05-02T00:00:00+00:00"