remove Connection.server_version and use host metadata

cassandra/cluster.py

@@ -2357,8 +2357,6 @@ class ControlConnection(object):
             if partitioner and tokens:
                 token_map[host] = tokens
 
-            connection.server_version = local_row['release_version']
-
         # Check metadata.partitioner to see if we haven't built anything yet. If
         # every node in the cluster was in the contact points, we won't discover
         # any new nodes, so we need this additional check.  (See PYTHON-90)

cassandra/connection.py

@@ -232,8 +232,6 @@ class Connection(object):
     is_control_connection = False
     signaled_error = False  # used for flagging at the pool level
 
-    _server_version = None
-
     _iobuf = None
     _current_frame = None
 
@@ -829,18 +827,6 @@ class Connection(object):
     def reset_idle(self):
         self.msg_received = False
 
-    @property
-    def server_version(self):
-        if self._server_version is None:
-            query_message = QueryMessage(query="SELECT release_version FROM system.local", consistency_level=ConsistencyLevel.ONE)
-            message = self.wait_for_response(query_message)
-            self._server_version = message.results[1][0][0]  # (col names, rows)[rows][first row][only item]
-        return self._server_version
-
-    @server_version.setter
-    def server_version(self, version):
-        self._server_version = version
-
     def __str__(self):
         status = ""
         if self.is_defunct:

cassandra/metadata.py

@@ -117,13 +117,15 @@ class Metadata(object):
 
     def refresh(self, connection, timeout, target_type=None, change_type=None, **kwargs):
 
+        server_version = self.get_host(connection.host).release_version
+        parser = get_schema_parser(connection, server_version, timeout)
+
         if not target_type:
-            self._rebuild_all(connection, timeout)
+            self._rebuild_all(parser)
             return
 
         tt_lower = target_type.lower()
         try:
-            parser = get_schema_parser(connection, timeout)
             parse_method = getattr(parser, 'get_' + tt_lower)
             meta = parse_method(self.keyspaces, **kwargs)
             if meta:
@@ -135,12 +137,7 @@ class Metadata(object):
         except AttributeError:
             raise ValueError("Unknown schema target_type: '%s'" % target_type)
 
-    def _rebuild_all(self, connection, timeout):
-        """
-        For internal use only.
-        """
-        parser = get_schema_parser(connection, timeout)
-
+    def _rebuild_all(self, parser):
         current_keyspaces = set()
         for keyspace_meta in parser.get_all_keyspaces():
             current_keyspaces.add(keyspace_meta.name)
@@ -2455,8 +2452,7 @@ class MaterializedViewMetadata(object):
         return self.as_cql_query(formatted=True) + ";"
 
 
-def get_schema_parser(connection, timeout):
-    server_version = connection.server_version
+def get_schema_parser(connection, server_version, timeout):
     if server_version.startswith('3'):
         return SchemaParserV3(connection, timeout)
     else:

tests/unit/test_metadata.py

@@ -380,9 +380,7 @@ class IndexTest(unittest.TestCase):
         column_meta.table.name = 'table_name_here'
         column_meta.table.keyspace_name = 'keyspace_name_here'
         column_meta.table.columns = {column_meta.name: column_meta}
-        connection = Mock()
-        connection.server_version = '2.1.0'
-        parser = get_schema_parser(connection, 0.1)
+        parser = get_schema_parser(Mock(), '2.1.0', 0.1)
 
         row = {'index_name': 'index_name_here', 'index_type': 'index_type_here'}
         index_meta = parser._build_index_metadata(column_meta, row)