make gettting options with falback simpler

lib/ansible/plugins/__init__.py

@@ -90,6 +90,21 @@ def get_options(self, hostvars=None):
             options[option] = self.get_option(option, hostvars=hostvars)
         return options
 
+    def get_ff_option(self, *options, hostvars=None, pc=None):
+        ''' convinience function for when plugins have not followed strict conventions (user/remote_user)
+            and/or relied on playcontext, which is not strictly up2date, specially in loops. '''
+        for option in options:
+            if self.has_option(option):
+                return self.get_option(option, hostvars)
+
+        # fallback to play context
+        if pc is not None:
+            for option in options:
+                if hasattr(pc, option):
+                    return getattr(pc, option)
+
+        raise KeyError("The %s plugin '%s' does not support any of these options: %s" % (self.plugin_type, self._load_name, ', '.join(options))
+
     def set_option(self, option, value):
         self._options[option] = C.config.get_config_value(option, plugin_type=self.plugin_type, plugin_name=self._load_name, direct={option: value})