Add show limits command

* This is a combination of the compute and volume API limits as they are
  very similar.  As such, the command lives in a new command group
  'openstack.common' that is unversioned.
* Implements 'limits show [--absolute|--rate]

Updated for https://review.openstack.org/#/c/36772/

Bug: 1172057

Change-Id: I2bd181cd0d098f7143360ae67944c2f221379af5

openstackclient/common/limits.py

@@ -0,0 +1,79 @@
+#   Copyright 2012-2013 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.
+#
+
+"""Limits Action Implementation"""
+
+import itertools
+import logging
+
+from cliff import lister
+
+from openstackclient.common import utils
+
+
+class ShowLimits(lister.Lister):
+    """Show compute and volume limits"""
+
+    log = logging.getLogger(__name__ + '.ShowLimits')
+
+    def get_parser(self, prog_name):
+        parser = super(ShowLimits, self).get_parser(prog_name)
+        type_group = parser.add_mutually_exclusive_group()
+        type_group.add_argument(
+            "--absolute",
+            dest="is_absolute",
+            action="store_true",
+            default=False,
+            help="Show absolute limits")
+        type_group.add_argument(
+            "--rate",
+            dest="is_rate",
+            action="store_true",
+            default=False,
+            help="Show rate limits")
+        parser.add_argument(
+            "--reserved",
+            dest="is_reserved",
+            action="store_true",
+            default=False,
+            help="Include reservations count [only valid with --absolute]")
+        return parser
+
+    def take_action(self, parsed_args):
+        self.log.debug('take_action(%s)' % parsed_args)
+
+        compute_client = self.app.client_manager.compute
+        volume_client = self.app.client_manager.volume
+
+        compute_limits = compute_client.limits.get(parsed_args.is_reserved)
+        volume_limits = volume_client.limits.get()
+
+        if parsed_args.is_absolute:
+            compute_limits = compute_limits.absolute
+            volume_limits = volume_limits.absolute
+            columns = ["Name", "Value"]
+            return (columns, (utils.get_item_properties(s, columns)
+                    for s in itertools.chain(compute_limits, volume_limits)))
+
+        elif parsed_args.is_rate:
+            compute_limits = compute_limits.rate
+            volume_limits = volume_limits.rate
+            columns = ["Verb", "URI", "Value", "Remain", "Unit",
+                       "Next Available"]
+            return (columns, (utils.get_item_properties(s, columns)
+                    for s in itertools.chain(compute_limits, volume_limits)))
+
+        else:
+            return ({}, {})

openstackclient/shell.py

@@ -331,6 +331,10 @@ class OpenStackShell(app.App):
             self.command_manager.add_command_group(
                 'openstack.' + api + version)
 
+        # Commands that span multiple APIs
+        self.command_manager.add_command_group(
+            'openstack.common')
+
         # This is the naive extension implementation referred to in
         # blueprint 'client-extensions'
         # Extension modules can register their commands in an

setup.cfg

@@ -31,6 +31,9 @@ console_scripts =
 
 openstack.cli =
 
+openstack.common =
+    limits_show = openstackclient.common.limits:ShowLimits
+
 openstack.identity.v2_0 =
     ec2_credentials_create = openstackclient.identity.v2_0.ec2creds:CreateEC2Creds
     ec2_credentials_delete = openstackclient.identity.v2_0.ec2creds:DeleteEC2Creds