[_768] reload option

[_768] add test

[_768] reasonable handling of _meta

Author: d-w-moore

irods/manager/metadata_manager.py

@@ -83,6 +83,9 @@ def _model_class_to_resource_description(model_cls):
         }[model_cls]
 
     def get(self, model_cls, path):
+        if not path:
+            # Short circuit.  This should be of the same type as the object returned at the function's end.
+            return []
         resource_type = self._model_class_to_resource_type(model_cls)
         model = {
             "d": DataObjectMeta,

irods/meta.py

@@ -107,7 +107,11 @@ def __init__(self, manager, model_cls, path):
         self._reset_metadata()
 
     def _reset_metadata(self):
-        self._meta = self._manager.get(self._model_cls, self._path)
+        m = self._manager
+        if not hasattr(self,"_meta"):
+            self._meta = m.get(None, "")
+        if m._opts.setdefault('reload',True):
+            self._meta = m.get(self._model_cls, self._path)
 
     def get_all(self, key):
         """

irods/test/meta_test.py

@@ -822,6 +822,25 @@ def test_cascading_changes_of_metadata_manager_options__issue_709(self):
             if d:
                 d.unlink(force=True)
 
+    def test_reload_can_be_deactivated__issue_768(self):
+        # Set an initial AVU
+        metacoll = self.obj.metadata
+        metacoll.set(i:=iRODSMeta('aa','bb','cc'))
+
+        # Initial defaults will always reload the AVU list from the server, so new AVU should be seen.
+        self.assertIn(i, metacoll.items())
+
+        # Setting reload option to False will prevent reload of object AVUs, so an AVU just set should not be seen.
+        (mc:=metacoll(reload=False)).set(i2:=iRODSMeta('xx','yy','zz'))
+        items = mc.items()
+        self.assertIn(i, items)
+        self.assertNotIn(i2, items)
+
+        # Restore old setting.  Check that both AVUs are seen as present.
+        items_reloaded = mc(reload=True).items()
+        self.assertIn(i, items_reloaded)
+        self.assertIn(i2, items_reloaded)
+
 if __name__ == "__main__":
     # let the tests find the parent irods lib
     sys.path.insert(0, os.path.abspath("../.."))