Improve logging around connection errors (#595)

+ don't try to reset broken connections when releasing back into pool

Backport of #594

Author: robsdedude

neo4j/io/__init__.py

@@ -335,7 +335,7 @@ def open(cls, address, *, auth=None, timeout=None, routing_context=None, **pool_
             from neo4j.io._bolt4 import Bolt4x3
             connection = Bolt4x3(address, s, pool_config.max_connection_lifetime, auth=auth, user_agent=pool_config.user_agent, routing_context=routing_context)
         else:
-            log.debug("[#%04X]  S: <CLOSE>", s.getpeername()[1])
+            log.debug("[#%04X]  S: <CLOSE>", s.getsockname()[1])
             _close_socket(s)
 
             supported_versions = Bolt.protocol_handlers().keys()
@@ -540,7 +540,7 @@ def _set_defunct(self, message, error=None, silent=False):
         direct_driver = isinstance(self.pool, BoltPool)
 
         if error:
-            log.error(str(error))
+            log.debug("[#%04X] %s", self.socket.getsockname()[1], error)
         log.error(message)
         # We were attempting to receive data but the connection
         # has unexpectedly terminated. So, we need to close the
@@ -703,7 +703,9 @@ def release(self, *connections):
         """
         with self.lock:
             for connection in connections:
-                if not connection.is_reset:
+                if not (connection.is_reset
+                        or connection.defunct()
+                        or connection.closed()):
                     try:
                         connection.reset()
                     except (Neo4jError, DriverError, BoltError) as e: