module_helper.py Breakdown (#2393) (#2492)

* break down of module_helper into smaller pieces, keeping compatibility

* removed abc.ABC (py3 only) from code + fixed reference to vars.py

* multiple changes:

- mh.base - moved more functionalities to ModuleHelperBase
- mh.mixins.(cmd, state) - CmdMixin no longer inherits from ModuleHelperBase
- mh.mixins.deps - DependencyMixin now overrides run() method to test dependency
- mh.mixins.vars - created class VarsMixin
- mh.module_helper - moved functions to base class, added VarsMixin
- module_helper - importing AnsibleModule as well, for backward compatibility in test

* removed unnecessary __all__

* make pylint happy

* PR adjustments + bot config + changelog frag

* Update plugins/module_utils/mh/module_helper.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* Update plugins/module_utils/mh/module_helper.py

Co-authored-by: Felix Fontein <felix@fontein.de>

Co-authored-by: Felix Fontein <felix@fontein.de>
(cherry picked from commit d22dd5056e)

Co-authored-by: Alexei Znamensky <103110+russoz@users.noreply.github.com>

plugins/module_utils/mh/module_helper.py

@@ -0,0 +1,79 @@
+# -*- coding: utf-8 -*-
+# (c) 2020, Alexei Znamensky <russoz@gmail.com>
+# Copyright: (c) 2020, Ansible Project
+# Simplified BSD License (see licenses/simplified_bsd.txt or https://opensource.org/licenses/BSD-2-Clause)
+
+from __future__ import absolute_import, division, print_function
+__metaclass__ = type
+
+from ansible.module_utils.common.dict_transformations import dict_merge
+
+from ansible_collections.community.general.plugins.module_utils.mh.base import ModuleHelperBase, AnsibleModule
+from ansible_collections.community.general.plugins.module_utils.mh.mixins.cmd import CmdMixin
+from ansible_collections.community.general.plugins.module_utils.mh.mixins.state import StateMixin
+from ansible_collections.community.general.plugins.module_utils.mh.mixins.deps import DependencyMixin
+from ansible_collections.community.general.plugins.module_utils.mh.mixins.vars import VarsMixin, VarDict as _VD
+
+
+class ModuleHelper(VarsMixin, DependencyMixin, ModuleHelperBase):
+    _output_conflict_list = ('msg', 'exception', 'output', 'vars', 'changed')
+    facts_name = None
+    output_params = ()
+    diff_params = ()
+    change_params = ()
+    facts_params = ()
+
+    VarDict = _VD  # for backward compatibility, will be deprecated at some point
+
+    def __init__(self, module=None):
+        super(ModuleHelper, self).__init__(module)
+        for name, value in self.module.params.items():
+            self.vars.set(
+                name, value,
+                diff=name in self.diff_params,
+                output=name in self.output_params,
+                change=None if not self.change_params else name in self.change_params,
+                fact=name in self.facts_params,
+            )
+
+    def update_output(self, **kwargs):
+        self.update_vars(meta={"output": True}, **kwargs)
+
+    def update_facts(self, **kwargs):
+        self.update_vars(meta={"fact": True}, **kwargs)
+
+    def _vars_changed(self):
+        return any(self.vars.has_changed(v) for v in self.vars.change_vars())
+
+    def has_changed(self):
+        return self.changed or self._vars_changed()
+
+    @property
+    def output(self):
+        result = dict(self.vars.output())
+        if self.facts_name:
+            facts = self.vars.facts()
+            if facts is not None:
+                result['ansible_facts'] = {self.facts_name: facts}
+        if self.module._diff:
+            diff = result.get('diff', {})
+            vars_diff = self.vars.diff() or {}
+            result['diff'] = dict_merge(dict(diff), vars_diff)
+
+        for varname in result:
+            if varname in self._output_conflict_list:
+                result["_" + varname] = result[varname]
+                del result[varname]
+        return result
+
+
+class StateModuleHelper(StateMixin, ModuleHelper):
+    pass
+
+
+class CmdModuleHelper(CmdMixin, ModuleHelper):
+    pass
+
+
+class CmdStateModuleHelper(CmdMixin, StateMixin, ModuleHelper):
+    pass