add escalator frame

JIRA:ESCALATOR-35

This patch will support escalator service,and there is not real command can use.
With this code, you can test with '/usr/bin/escalator-api' from command line.When
service is up, you can use "curl http://127.0.0.1:19393" for verify the service.

Change-Id: I5154328adf82ec70acb6e0ce12ef4b1701f7b710
Signed-off-by: Jing Sun <sun.jing22@zte.com.cn>

1 files changed, 97 insertions, 0 deletions

diff --git a/api/escalator/api/policy.py b/api/escalator/api/policy.py
new file mode 100644
index 0000000..4d94f51
--- /dev/null
+++ b/api/escalator/api/policy.py
@@ -0,0 +1,97 @@
+# Copyright (c) 2011 OpenStack Foundation
+# Copyright 2013 IBM Corp.
+# 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.
+
+"""Policy Engine For Escalator"""
+
+
+from oslo_config import cfg
+from oslo_log import log as logging
+from oslo_policy import policy
+
+from escalator.common import exception
+from escalator import i18n
+
+
+LOG = logging.getLogger(__name__)
+CONF = cfg.CONF
+
+DEFAULT_RULES = policy.Rules.from_dict({
+    'context_is_admin': 'role:admin',
+    'default': '@',
+    'manage_image_cache': 'role:admin',
+})
+
+_ = i18n._
+_LI = i18n._LI
+_LW = i18n._LW
+
+
+class Enforcer(policy.Enforcer):
+    """Responsible for loading and enforcing rules"""
+
+    def __init__(self):
+        if CONF.find_file(CONF.oslo_policy.policy_file):
+            kwargs = dict(rules=None, use_conf=True)
+        else:
+            kwargs = dict(rules=DEFAULT_RULES, use_conf=False)
+        super(Enforcer, self).__init__(CONF, overwrite=False, **kwargs)
+
+    def add_rules(self, rules):
+        """Add new rules to the Rules object"""
+        self.set_rules(rules, overwrite=False, use_conf=self.use_conf)
+
+    def enforce(self, context, action, target):
+        """Verifies that the action is valid on the target in this context.
+
+           :param context: Escalator request context
+           :param action: String representing the action to be checked
+           :param target: Dictionary representing the object of the action.
+           :raises: `escalator.common.exception.Forbidden`
+           :returns: A non-False value if access is allowed.
+        """
+        credentials = {
+            'roles': context.roles,
+            'user': context.user,
+            'tenant': context.tenant,
+        }
+        return super(Enforcer, self).enforce(action, target, credentials,
+                                             do_raise=True,
+                                             exc=exception.Forbidden,
+                                             action=action)
+
+    def check(self, context, action, target):
+        """Verifies that the action is valid on the target in this context.
+
+           :param context: Escalator request context
+           :param action: String representing the action to be checked
+           :param target: Dictionary representing the object of the action.
+           :returns: A non-False value if access is allowed.
+        """
+        credentials = {
+            'roles': context.roles,
+            'user': context.user,
+            'tenant': context.tenant,
+        }
+        return super(Enforcer, self).enforce(action, target, credentials)
+
+    def check_is_admin(self, context):
+        """Check if the given context is associated with an admin role,
+           as defined via the 'context_is_admin' RBAC rule.
+
+           :param context: Escalator request context
+           :returns: A non-False value if context role is admin.
+        """
+        return self.check(context, 'context_is_admin', context.to_dict())