deal with null/none connections

fixes #23621
pushed 'connection resolution' to play_context
override fieldattribute getter

lib/ansible/executor/task_executor.py

@@ -20,7 +20,6 @@ from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
 import base64
-import sys
 import time
 import traceback
 
@@ -722,27 +721,12 @@ class TaskExecutor:
                     if isinstance(i, string_types) and i.startswith("ansible_") and i.endswith("_interpreter"):
                         variables[i] = delegated_vars[i]
 
-        conn_type = self._play_context.connection
+        # if using persistent paramiko connections (or the action has set the FORCE_PERSISTENT_CONNECTION attribute to True),
-        if conn_type == 'smart':
-            conn_type = 'ssh'
-            if sys.platform.startswith('darwin') and self._play_context.password:
-                # due to a current bug in sshpass on OSX, which can trigger
-                # a kernel panic even for non-privileged users, we revert to
-                # paramiko on that OS when a SSH password is specified
-                conn_type = "paramiko"
-            else:
-                # see if SSH can support ControlPersist if not use paramiko
-                if not check_for_controlpersist(self._play_context.ssh_executable):
-                    conn_type = "paramiko"
-
-        # if someone did `connection: persistent`, default it to using a persistent paramiko connection to avoid problems
-        if conn_type == 'persistent':
-            self._play_context.connection = 'paramiko'
-
-        # if using persistent connections (or the action has set the FORCE_PERSISTENT_CONNECTION attribute to True),
         # then we use the persistent connection plugion. Otherwise load the requested connection plugin
-        elif C.USE_PERSISTENT_CONNECTIONS or getattr(self, 'FORCE_PERSISTENT_CONNECTION', False):
+        if C.USE_PERSISTENT_CONNECTIONS or getattr(self, 'FORCE_PERSISTENT_CONNECTION', False):
             conn_type == 'persistent'
+        else:
+            conn_type = self._play_context.connection
 
         connection = self._shared_loader_obj.connection_loader.get(conn_type, self._play_context, self._new_stdin)
 

lib/ansible/playbook/play_context.py

@@ -26,14 +26,16 @@ import pwd
 import random
 import re
 import string
+import sys
 
 from ansible import constants as C
 from ansible.errors import AnsibleError
-from ansible.module_utils.six import iteritems, string_types
+from ansible.module_utils.six import iteritems
 from ansible.module_utils.six.moves import shlex_quote
 from ansible.module_utils._text import to_bytes
 from ansible.playbook.attribute import FieldAttribute
 from ansible.playbook.base import Base
+from ansible.utils.ssh_functions import check_for_controlpersist
 
 
 boolean = C.mk_boolean
@@ -241,6 +243,7 @@ class PlayContext(Base):
         if play:
             self.set_play(play)
 
+
     def set_play(self, play):
         '''
         Configures this connection information instance with data from
@@ -611,3 +614,28 @@ class PlayContext(Base):
                         variables[var_opt] = var_val
             except AttributeError:
                 continue
+
+    def _get_attr_connection(self):
+        ''' connections are special, this takes care of responding correctly '''
+        conn_type = None
+        if self._attributes['connection'] == 'smart':
+            conn_type = 'ssh'
+            if sys.platform.startswith('darwin') and self.password:
+                # due to a current bug in sshpass on OSX, which can trigger
+                # a kernel panic even for non-privileged users, we revert to
+                # paramiko on that OS when a SSH password is specified
+                conn_type = "paramiko"
+            else:
+                # see if SSH can support ControlPersist if not use paramiko
+                if not check_for_controlpersist(self.ssh_executable):
+                    conn_type = "paramiko"
+
+        # if someone did `connection: persistent`, default it to using a persistent paramiko connection to avoid problems
+        elif self._attributes['connection'] == 'persistent':
+            conn_type = 'paramiko'
+
+        if conn_type:
+            self.connection = conn_type
+
+        return self._attributes['connection']
+

lib/ansible/plugins/strategy/__init__.py

@@ -19,6 +19,7 @@
 from __future__ import (absolute_import, division, print_function)
 __metaclass__ = type
 
+import os
 import threading
 import time
 
@@ -903,9 +904,12 @@ class StrategyBase:
                         iterator._host_states[host.name].run_state = iterator.ITERATING_COMPLETE
                 msg="ending play"
         elif meta_action == 'reset_connection':
-            connection = connection_loader.get(play_context.connection, play_context, '/dev/null')
+            connection = connection_loader.get(play_context.connection, play_context, os.devnull)
+            if connection:
                 connection.reset()
                 msg= 'reset connection'
+            else:
+                msg= 'no connection, nothing to reset'
         else:
             raise AnsibleError("invalid meta action requested: %s" % meta_action, obj=task._ds)
 

test/units/playbook/test_play_context.py

@@ -53,7 +53,7 @@ class TestPlayContext(unittest.TestCase):
     def test_play_context(self):
         (options, args) = self._parser.parse_args(['-vv', '--check'])
         play_context = PlayContext(options=options)
-        self.assertEqual(play_context.connection, C.DEFAULT_TRANSPORT)
+        self.assertEqual(play_context._attributes['connection'], C.DEFAULT_TRANSPORT)
         self.assertEqual(play_context.remote_addr, None)
         self.assertEqual(play_context.remote_user, None)
         self.assertEqual(play_context.password, '')