Create name property in a Cluster object

It returns self.member.name and simplifies later usage in code.

helpers/dcs.py

@@ -58,6 +58,10 @@ class Leader(namedtuple('Leader', 'index,expiration,ttl,member')):
     :param ttl: ttl of the leader key
     :param member: reference to a `Member` object which represents current leader (see `Cluster.members`)"""
 
+    @property
+    def name(self):
+        return self.member.name
+
 
 class Cluster(namedtuple('Cluster', 'initialize,leader,last_leader_operation,members')):
     """Immutable object (namedtuple) which represents PostgreSQL cluster.
@@ -69,7 +73,7 @@ class Cluster(namedtuple('Cluster', 'initialize,leader,last_leader_operation,mem
     :param members: list of Member object, all PostgreSQL cluster members including leader"""
 
     def is_unlocked(self):
-        return not (self.leader and self.leader.member.name)
+        return not (self.leader and self.leader.name)
 
 
 class AbstractDCS:
@@ -83,7 +87,8 @@ class AbstractDCS:
             i.e.: `zookeeper` for zookeeper, `etcd` for etcd, etc...
         """
         self._name = name
-        self._base_path = '/service/' + config['scope']
+        self._scope = config['scope']
+        self._base_path = '/service/' + self._scope
 
     def client_path(self, path):
         return self._base_path + path

helpers/etcd.py

@@ -185,7 +185,8 @@ class Etcd(AbstractDCS):
             self.cluster = Cluster(initialize, leader, last_leader_operation, members)
             return self.cluster
         except etcd.EtcdKeyNotFound:
-            return Cluster(False, None, None, [])
+            self.cluster = Cluster(False, None, None, [])
+            return self.cluster
         except:
             logger.exception('get_cluster')
 
@@ -226,14 +227,14 @@ class Etcd(AbstractDCS):
 
     def watch(self, timeout):
         # watch on leader key changes if it is defined and current node is not lock owner
-        if self.cluster and self.cluster.leader and self.cluster.leader.member.name != self._name:
+        if self.cluster and self.cluster.leader and self.cluster.leader.name != self._name:
             end_time = time.time() + timeout
             index = self.cluster.leader.index
 
             while index and timeout >= 1:  # when timeout is too small urllib3 doesn't have enough time to connect
                 try:
                     res = self.client.watch(self.client_path('/leader'), index=index + 1, timeout=timeout)
-                    if res.action not in ['set', 'compareAndSwap'] or res.value != self.cluster.leader.member.name:
+                    if res.action not in ['set', 'compareAndSwap'] or res.value != self.cluster.leader.name:
                         return
                     index = res.modifiedIndex
                 except urllib3.exceptions.TimeoutError:

helpers/ha.py

@@ -31,7 +31,7 @@ class Ha:
         return self.dcs.update_leader(self.state_handler)
 
     def has_lock(self):
-        lock_owner = self.cluster.leader and self.cluster.leader.member.name
+        lock_owner = self.cluster.leader and self.cluster.leader.name
         logger.info('Lock owner: %s; I am %s', lock_owner, self.state_handler.name)
         return lock_owner == self.state_handler.name
 

helpers/zookeeper.py

@@ -217,7 +217,7 @@ class ZooKeeper(AbstractDCS):
         return True
 
     def delete_leader(self):
-        if isinstance(self.leader, Leader) and self.leader.member.name == self._name:
+        if isinstance(self.leader, Leader) and self.leader.name == self._name:
             self.client.delete(self.client_path('/leader'))
 
     def watch(self, timeout):