issue #294: ansible: fix mixed vanilla/Mitogen runs.

Don't bother trying to understand what damage PluginLoader has done to
ansible.plugins.* namespace, just ask it for the base class instead.

ansible_mitogen/loaders.py

@@ -0,0 +1,46 @@
+# Copyright 2017, David Wilson
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+#
+# 1. Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+#
+# 2. Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+#
+# 3. Neither the name of the copyright holder nor the names of its contributors
+# may be used to endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+"""
+Stable names for PluginLoader instances across Ansible versions.
+"""
+
+from __future__ import absolute_import
+
+try:
+    from ansible.plugins.loader import action_loader
+    from ansible.plugins.loader import connection_loader
+    from ansible.plugins.loader import module_loader
+    from ansible.plugins.loader import module_utils_loader
+    from ansible.plugins.loader import strategy_loader
+except ImportError:  # Ansible <2.4
+    from ansible.plugins import action_loader
+    from ansible.plugins import connection_loader
+    from ansible.plugins import module_loader
+    from ansible.plugins import module_utils_loader
+    from ansible.plugins import strategy_loader

ansible_mitogen/planner.py

@@ -47,13 +47,7 @@ import ansible.errors
 import ansible.module_utils
 import mitogen.core
 
-try:
-    from ansible.plugins.loader import module_loader
-    from ansible.plugins.loader import module_utils_loader
-except ImportError:  # Ansible <2.4
-    from ansible.plugins import module_loader
-    from ansible.plugins import module_utils_loader
-
+import ansible_mitogen.loaders
 import ansible_mitogen.target
 
 
@@ -322,7 +316,9 @@ class NewStylePlanner(ScriptPlanner):
     def get_search_path(self):
         return tuple(
             path
-            for path in module_utils_loader._get_paths(subdirs=False)
+            for path in ansible_mitogen.loaders.module_utils_loader._get_paths(
+                subdirs=False
+            )
             if os.path.isdir(path)
         )
 
@@ -397,7 +393,7 @@ _planners = [
 
 
 def get_module_data(name):
-    path = module_loader.find_plugin(name, '')
+    path = ansible_mitogen.loaders.module_loader.find_plugin(name, '')
     with open(path, 'rb') as fp:
         source = fp.read()
     return mitogen.core.to_text(path), source

ansible_mitogen/plugins/strategy/mitogen_free.py

@@ -51,10 +51,11 @@ except ImportError:
     sys.path.insert(0, os.path.abspath(os.path.join(base_dir, '../../..')))
     del base_dir
 
+import ansible_mitogen.loaders
 import ansible_mitogen.strategy
-import ansible.plugins.strategy.free
 
 
-class StrategyModule(ansible_mitogen.strategy.StrategyMixin,
-                     ansible.plugins.strategy.free.StrategyModule):
+Base = ansible_mitogen.loaders.strategy_loader.get('free', class_only=True)
+
+class StrategyModule(ansible_mitogen.strategy.StrategyMixin, Base):
     pass

ansible_mitogen/plugins/strategy/mitogen_linear.py

@@ -51,10 +51,11 @@ except ImportError:
     sys.path.insert(0, os.path.abspath(os.path.join(base_dir, '../../..')))
     del base_dir
 
+import ansible_mitogen.loaders
 import ansible_mitogen.strategy
-import ansible.plugins.strategy.linear
 
 
-class StrategyModule(ansible_mitogen.strategy.StrategyMixin,
-                     ansible.plugins.strategy.linear.StrategyModule):
+Base = ansible_mitogen.loaders.strategy_loader.get('linear', class_only=True)
+
+class StrategyModule(ansible_mitogen.strategy.StrategyMixin, Base):
     pass

ansible_mitogen/strategy.py

@@ -29,16 +29,10 @@
 from __future__ import absolute_import
 import os
 
+import ansible_mitogen.loaders
 import ansible_mitogen.mixins
 import ansible_mitogen.process
 
-try:
-    from ansible.plugins.loader import action_loader
-    from ansible.plugins.loader import connection_loader
-except ImportError:  # Ansible <2.4
-    from ansible.plugins import action_loader
-    from ansible.plugins import connection_loader
-
 
 def wrap_action_loader__get(name, *args, **kwargs):
     """
@@ -138,19 +132,19 @@ class StrategyMixin(object):
         with references to the real functions.
         """
         global action_loader__get
-        action_loader__get = action_loader.get
-        action_loader.get = wrap_action_loader__get
+        action_loader__get = ansible_mitogen.loaders.action_loader.get
+        ansible_mitogen.loaders.action_loader.get = wrap_action_loader__get
 
         global connection_loader__get
-        connection_loader__get = connection_loader.get
-        connection_loader.get = wrap_connection_loader__get
+        connection_loader__get = ansible_mitogen.loaders.connection_loader.get
+        ansible_mitogen.loaders.connection_loader.get = wrap_connection_loader__get
 
     def _remove_wrappers(self):
         """
         Uninstall the PluginLoader monkey patches.
         """
-        action_loader.get = action_loader__get
-        connection_loader.get = connection_loader__get
+        ansible_mitogen.loaders.action_loader.get = action_loader__get
+        ansible_mitogen.loaders.connection_loader.get = connection_loader__get
 
     def _add_connection_plugin_path(self):
         """
@@ -158,7 +152,9 @@ class StrategyMixin(object):
         avoiding the need for manual configuration.
         """
         base_dir = os.path.join(os.path.dirname(__file__), 'plugins')
-        connection_loader.add_directory(os.path.join(base_dir, 'connection'))
+        ansible_mitogen.loaders.connection_loader.add_directory(
+            os.path.join(base_dir, 'connection')
+        )
 
     def run(self, iterator, play_context, result=0):
         """

tests/ansible/integration/all.yml

@@ -13,4 +13,5 @@
 - import_playbook: remote_tmp/all.yml
 - import_playbook: runner/all.yml
 - import_playbook: ssh/all.yml
+- import_playbook: strategy/all.yml
 - import_playbook: glibc_caches/all.yml

tests/ansible/integration/strategy/all.yml

@@ -0,0 +1 @@
+- import_playbook: mixed_vanilla_ansible.yml

tests/ansible/integration/strategy/mixed_vanilla_ansible.yml

@@ -0,0 +1,45 @@
+
+# issue #294: ensure running mixed vanilla/Mitogen succeeds.
+
+- name: integration/strategy/mixed_vanilla_ansible.yml (linear)
+  hosts: test-targets
+  any_errors_fatal: true
+  strategy: linear
+  tasks:
+    - custom_python_detect_environment:
+      register: out
+    - assert:
+        that: not out.mitogen_loaded
+
+    - determine_strategy:
+    - assert:
+        that: strategy == 'ansible.plugins.strategy.linear.StrategyModule'
+
+- name: integration/strategy/mixed_vanilla_ansible.yml (mitogen_linear)
+  hosts: test-targets
+  any_errors_fatal: true
+  strategy: mitogen_linear
+  tasks:
+    - custom_python_detect_environment:
+      register: out
+    - assert:
+        that: out.mitogen_loaded
+
+    - determine_strategy:
+    - assert:
+        that: strategy == 'ansible.plugins.strategy.mitogen_linear.StrategyModule'
+
+
+- name: integration/strategy/mixed_vanilla_ansible.yml (linear)
+  hosts: test-targets
+  any_errors_fatal: true
+  strategy: linear
+  tasks:
+    - custom_python_detect_environment:
+      register: out
+    - assert:
+        that: not out.mitogen_loaded
+
+    - determine_strategy:
+    - assert:
+        that: strategy == 'ansible.plugins.strategy.linear.StrategyModule'