Implement plugin filtering

lib/ansible/plugins/loader.py

@@ -17,8 +17,10 @@ import warnings
 from collections import defaultdict
 
 from ansible import constants as C
-from ansible.plugins import get_plugin_class, MODULE_CACHE, PATH_CACHE, PLUGIN_PATH_CACHE
+from ansible.errors import AnsibleError
 from ansible.module_utils._text import to_text
+from ansible.parsing.utils.yaml import from_yaml
+from ansible.plugins import get_plugin_class, MODULE_CACHE, PATH_CACHE, PLUGIN_PATH_CACHE
 from ansible.utils.plugin_docs import get_docstring
 
 try:
@@ -235,6 +237,10 @@ class PluginLoader:
     def find_plugin(self, name, mod_type='', ignore_deprecated=False, check_aliases=False):
         ''' Find a plugin named name '''
 
+        global _PLUGIN_FILTERS
+        if name in _PLUGIN_FILTERS[self.package]:
+            return None
+
         if mod_type:
             suffix = mod_type
         elif self.class_name:
@@ -405,6 +411,8 @@ class PluginLoader:
     def all(self, *args, **kwargs):
         ''' instantiates all plugins with the same arguments '''
 
+        global _PLUGIN_FILTERS
+
         path_only = kwargs.pop('path_only', False)
         class_only = kwargs.pop('class_only', False)
         all_matches = []
@@ -416,7 +424,7 @@ class PluginLoader:
         for path in sorted(all_matches, key=os.path.basename):
             name = os.path.basename(os.path.splitext(path)[0])
 
-            if '__init__' in name:
+            if '__init__' in name or name in _PLUGIN_FILTERS[self.package]:
                 continue
 
             if path_only:
@@ -462,6 +470,63 @@ class PluginLoader:
             self._update_object(obj, name, path)
             yield obj
 
+
+def _load_plugin_filter():
+    filters = defaultdict(frozenset)
+
+    if C.PLUGIN_FILTERS_CFG is None:
+        filter_cfg = '/etc/ansible/plugin_filters.yml'
+        user_set = False
+    else:
+        filter_cfg = C.PLUGIN_FILTERS_CFG
+        user_set = True
+
+    if os.path.exists(filter_cfg):
+        with open(filter_cfg, 'rb') as f:
+            try:
+                filter_data = from_yaml(f.read())
+            except Exception as e:
+                display.warning(u'The plugin filter file, {0} was not parsable.'
+                                u' Skipping: {1}'.format(filter_cfg, to_text(e)))
+                return filters
+
+        try:
+            version = filter_data['filter_version']
+        except KeyError:
+            display.warning(u'The plugin filter file, {0} was invalid.'
+                            u' Skipping.'.format(filter_cfg))
+            return filters
+
+        # Try to convert for people specifying version as a float instead of string
+        version = to_text(version)
+        version = version.strip()
+
+        if version == u'1.0':
+            # Modules and action plugins share the same blacklist since the difference between the
+            # two isn't visible to the users
+            filters['ansible.modules'] = frozenset(filter_data['module_blacklist'])
+            filters['ansible.plugins.action'] = filters['ansible.modules']
+        else:
+            display.warning(u'The plugin filter file, {0} was a version not recognized by this'
+                            u' version of Ansible. Skipping.')
+    else:
+        if user_set:
+            display.warning(u'The plugin filter file, {0} does not exist.'
+                            u' Skipping.'.format(filter_cfg))
+
+    # Specialcase the stat module as Ansible can run very few things if stat is blacklisted.
+    if 'stat' in filters['ansible.modules']:
+        raise AnsibleError('The stat module was specified in the module blacklist file, {0}, but'
+                           ' Ansible will not function without the stat module.  Please remove stat'
+                           ' from the blacklist.'.format(filter_cfg))
+    return filters
+
+
+# TODO: All of the following is initialization code   It should be moved inside of an initialization
+# function which is called at some point early in the ansible and ansible-playbook CLI startup.
+
+_PLUGIN_FILTERS = _load_plugin_filter()
+
 # doc fragments first
 fragment_loader = PluginLoader(
     'ModuleDocFragment',
@@ -470,6 +535,7 @@ fragment_loader = PluginLoader(
     '',
 )
 
+
 action_loader = PluginLoader(
     'ActionModule',
     'ansible.plugins.action',