optimize file finding

lib/ansible/plugins/vars/host_group_vars.py

@@ -40,10 +40,11 @@ from ansible.inventory.host import Host
 from ansible.inventory.group import Group
 from ansible.utils.vars import combine_vars
 
+FOUND = {}
 
 class VarsModule(BaseVarsPlugin):
 
-    def get_vars(self, loader, path, entities):
+    def get_vars(self, loader, path, entities, cache=True):
         ''' parses the inventory file '''
 
         if not isinstance(entities, list):
@@ -61,20 +62,27 @@ class VarsModule(BaseVarsPlugin):
                 raise AnsibleParserError("Supplied entity must be Host or Group, got %s instead" % (type(entity)))
 
             try:
+                found_files = []
                 # load vars
                 opath = os.path.realpath(os.path.join(self._basedir, subdir))
-                b_opath = to_bytes(opath)
-                # no need to do much if path does not exist for basedir
-                if os.path.exists(b_opath):
-                    if os.path.isdir(b_opath):
-                        self._display.debug("\tprocessing dir %s" % opath)
-                        for found in self._find_vars_files(opath, entity.name):
-                            self._display.debug("READING %s" % found)
-                            new_data = loader.load_from_file(found, cache=True, unsafe=True)
-                            if new_data:  # ignore empty files
-                                data = combine_vars(data, new_data)
-                    else:
-                        self._display.warning("Found %s that is not a directory, skipping: %s" % (subdir, opath))
+                key = '%s.%s' % (entity.name, opath)
+                if cache and key in FOUND:
+                    found_files = FOUND[key]
+                else:
+                    b_opath = to_bytes(opath)
+                    # no need to do much if path does not exist for basedir
+                    if os.path.exists(b_opath):
+                        if os.path.isdir(b_opath):
+                            self._display.debug("\tprocessing dir %s" % opath)
+                            found_files = self._find_vars_files(opath, entity.name)
+                            FOUND[key] = found_files
+                        else:
+                            self._display.warning("Found %s that is not a directory, skipping: %s" % (subdir, opath))
+
+                for found in found_files:
+                    new_data = loader.load_from_file(found, cache=True, unsafe=True)
+                    if new_data:  # ignore empty files
+                        data = combine_vars(data, new_data)
 
             except Exception as e:
                 raise AnsibleParserError(to_text(e))