WIP version

This code has a shape now, but not functional at all.

senlin/engine/cluster.py

@@ -0,0 +1,97 @@
+# 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 uuid
+
+
+class Cluster(object):
+    '''
+    A cluster is a set of homogeneous objects of the same profile.
+
+    All operations are performed without further checking because the
+    checkings are supposed to be de done before/after/during an action is
+    excuted.
+    '''
+
+    statuses = (
+        ACTIVE, ERROR, DELETED, UPDATING,
+    ) = (
+        'ACTIVE', 'ERROR', 'DELETED', 'UPDATING',
+    )
+
+    def __init__(self, name, size, profile_type, **kwargs):
+        self.name = name
+        self.size = size
+        self.profile_type = profile_type
+        self.uuid = str(uuid.uuid4())
+        self.members = {}
+        self.policies = {}
+        self.domain = kwargs.get('domain')
+        self.project = kwargs.get('project')
+        self.user = kwargs.get('user')
+        self.parent = None
+        self.status = self.ACTIVE
+        self.status_reason = 'Initialized'
+        self._next_index = 0
+        self.tags = {}
+
+    @classmethod
+    def create(cls, name, size, profile_type, **kwargs):
+        cluster = cls(name, size, profile_type, kwargs)
+        # TODO: store this to database
+        # TODO: log events?
+        return cluster.uuid
+
+    @classmethod
+    def destroy(cls, cluster_id):
+        cluster = db_api.get_cluster(cluster_id)
+
+        # TODO: check if actions are working on and can be canceled
+        # TODO: destroy members
+
+        db_api.delete_cluster(cluster_id)
+        del cluster
+        return True
+
+    def next_index(self):
+        curr = self._next_index
+        self._next_index = self._next_index + 1
+        return curr
+
+    def get_members(self):
+        # This method will return each member with their associated profiles.
+        # Members may have different versions of the same profile type.
+        return {} 
+
+    def get_policies(self):
+        # policies are stored in database when policy association is created
+        # this method retrieves the attached policies from database
+        return {}
+
+    def add_members(self, member_ids):
+        pass
+
+    def remove_members(self, member_ids):
+        for member in member_ids:
+            res = Member.destroy(member)
+        return True
+
+    def attach_policy(self, policy_id):
+        '''
+        Attach specified policy instance to this cluster.
+        '''
+        # TODO: check conflicts with existing policies
+        self.policies.append(policy_id)
+
+    def detach_policy(self, policy_id):
+        # TODO: check if actions of specified policies are ongoing
+        self.policies.remove(policy_id)