Merge pull request #3124 from nathanielmanistaatgoogle/_end-fixes

Two fixes in grpc.framework.core._end

src/python/grpcio/grpc/framework/core/_end.py

@@ -30,7 +30,6 @@
 """Implementation of base.End."""
 
 import abc
-import enum
 import threading
 import uuid
 
@@ -75,7 +74,7 @@ def _abort(operations):
 
 def _cancel_futures(futures):
   for future in futures:
-    futures.cancel()
+    future.cancel()
 
 
 def _future_shutdown(lock, cycle, event):
@@ -83,8 +82,6 @@ def _future_shutdown(lock, cycle, event):
     with lock:
       _abort(cycle.operations.values())
       _cancel_futures(cycle.futures)
-      pool = cycle.pool
-    cycle.pool.shutdown(wait=True)
   return in_future
 
 
@@ -113,6 +110,7 @@ def _termination_action(lock, stats, operation_id, cycle):
         cycle.idle_actions = []
         if cycle.grace:
           _cancel_futures(cycle.futures)
+          cycle.pool.shutdown(wait=False)
   return termination_action