From b5d148b00a604c02e9f3622b5c0ffffb29649c6b Mon Sep 17 00:00:00 2001
From: Griatch <griatch@gmail.com>
Date: Mon, 27 Jul 2020 20:44:14 +0200
Subject: [PATCH] Optimize/fix searching objects by-attribute-value

---
 evennia/objects/manager.py   | 33 +++++++++------------------------
 evennia/utils/picklefield.py | 14 ++++++++++++--
 2 files changed, 21 insertions(+), 26 deletions(-)

diff --git a/evennia/objects/manager.py b/evennia/objects/manager.py
index 3e609991ff..a3db831149 100644
--- a/evennia/objects/manager.py
+++ b/evennia/objects/manager.py
@@ -154,7 +154,7 @@ class ObjectDBManager(TypedObjectManager):
 
         Args:
             attribute_name (str): Attribute key to search for.
-            attribute_value (str):  Attribute value to search for.
+            attribute_value (any):  Attribute value to search for. This can also be database objects.
             candidates (list, optional): Candidate objects to limit search to.
             typeclasses (list, optional): Python pats to restrict matches with.
 
@@ -175,31 +175,16 @@ class ObjectDBManager(TypedObjectManager):
         )
         type_restriction = typeclasses and Q(db_typeclass_path__in=make_iter(typeclasses)) or Q()
 
-        # This doesn't work if attribute_value is an object. Workaround below
-
-        if isinstance(attribute_value, (str, int, float, bool)):
-            return self.filter(
+        results = (
+            self
+            .filter(
                 cand_restriction
                 & type_restriction
-                & Q(db_attributes__db_key=attribute_name, db_attributes__db_value=attribute_value)
-            ).order_by("id")
-        else:
-            # We must loop for safety since the referenced lookup gives deepcopy error if attribute value is an object.
-            global _ATTR
-            if not _ATTR:
-                from evennia.typeclasses.models import Attribute as _ATTR
-            cands = list(
-                self.filter(
-                    cand_restriction & type_restriction & Q(db_attributes__db_key=attribute_name)
-                )
-            )
-            results = [
-                attr.objectdb_set.all()
-                for attr in _ATTR.objects.filter(
-                    objectdb__in=cands, db_value=attribute_value
-                ).order_by("id")
-            ]
-            return chain(*results)
+                & Q(db_attributes__db_key=attribute_name)
+                & Q(db_attributes__db_value=attribute_value))
+            .order_by("id")
+        )
+        return results
 
     def get_objs_with_db_property(self, property_name, candidates=None):
         """
diff --git a/evennia/utils/picklefield.py b/evennia/utils/picklefield.py
index 084fc6d638..2e62298ca5 100644
--- a/evennia/utils/picklefield.py
+++ b/evennia/utils/picklefield.py
@@ -31,7 +31,7 @@ Modified for Evennia by Griatch and the Evennia community.
 from ast import literal_eval
 from datetime import datetime
 
-from copy import deepcopy
+from copy import deepcopy, Error as CopyError
 from base64 import b64encode, b64decode
 from zlib import compress, decompress
 
@@ -44,6 +44,7 @@ from django.forms.widgets import Textarea
 
 from pickle import loads, dumps
 from django.utils.encoding import force_str
+from evennia.utils.dbserialize import pack_dbobj
 
 
 DEFAULT_PROTOCOL = 4
@@ -92,7 +93,16 @@ def dbsafe_encode(value, compress_object=False, pickle_protocol=DEFAULT_PROTOCOL
     # The reason this is important is because we do all of our lookups as
     # simple string matches, thus the character streams must be the same
     # for the lookups to work properly. See tests.py for more information.
-    value = dumps(deepcopy(value), protocol=pickle_protocol)
+    try:
+        value = deepcopy(value)
+    except CopyError:
+        # this can happen on a manager query where the search query string is a
+        # database model.
+        value = pack_dbobj(value)
+
+    value = dumps(value, protocol=pickle_protocol)
+
+
     if compress_object:
         value = compress(value)
     value = b64encode(value).decode()  # decode bytes to str