Don't check if host is in initial contact points when setting default local_dc

Author: sylwiaszunejko

cassandra/policies.py

@@ -245,7 +245,6 @@ def __init__(self, local_dc='', used_hosts_per_remote_dc=0):
         self.used_hosts_per_remote_dc = used_hosts_per_remote_dc
         self._dc_live_hosts = {}
         self._position = 0
-        self._endpoints = []
         LoadBalancingPolicy.__init__(self)
 
     def _dc(self, host):
@@ -255,11 +254,6 @@ def populate(self, cluster, hosts):
         for dc, dc_hosts in groupby(hosts, lambda h: self._dc(h)):
             self._dc_live_hosts[dc] = tuple({*dc_hosts, *self._dc_live_hosts.get(dc, [])})
 
-        if not self.local_dc:
-            self._endpoints = [
-                endpoint
-                for endpoint in cluster.endpoints_resolved]
-
         self._position = randint(0, len(hosts) - 1) if hosts else 0
 
     def distance(self, host):
@@ -301,13 +295,11 @@ def on_up(self, host):
         # not worrying about threads because this will happen during
         # control connection startup/refresh
         if not self.local_dc and host.datacenter:
-            if host.endpoint in self._endpoints:
-                self.local_dc = host.datacenter
-                log.info("Using datacenter '%s' for DCAwareRoundRobinPolicy (via host '%s'); "
-                         "if incorrect, please specify a local_dc to the constructor, "
-                         "or limit contact points to local cluster nodes" %
-                         (self.local_dc, host.endpoint))
-                del self._endpoints
+            self.local_dc = host.datacenter
+            log.info("Using datacenter '%s' for DCAwareRoundRobinPolicy (via host '%s'); "
+                        "if incorrect, please specify a local_dc to the constructor, "
+                        "or limit contact points to local cluster nodes" %
+                        (self.local_dc, host.endpoint))
 
         dc = self._dc(host)
         with self._hosts_lock:

tests/unit/test_policies.py

@@ -556,15 +556,6 @@ def test_default_dc(self):
         assert policy.local_dc != host_remote.datacenter
         assert policy.local_dc == host_local.datacenter
 
-        # contact DC second
-        policy = DCAwareRoundRobinPolicy()
-        policy.populate(cluster, [host_none])
-        assert not policy.local_dc
-        policy.on_add(host_remote)
-        policy.on_add(host_local)
-        assert policy.local_dc != host_remote.datacenter
-        assert policy.local_dc == host_local.datacenter
-
         # no DC
         policy = DCAwareRoundRobinPolicy()
         policy.populate(cluster, [host_none])
@@ -577,7 +568,7 @@ def test_default_dc(self):
         policy.populate(cluster, [host_none])
         assert not policy.local_dc
         policy.on_add(host_remote)
-        assert not policy.local_dc
+        assert policy.local_dc
 
 class TokenAwarePolicyTest(unittest.TestCase):