Python filtered models for room members

src/backend/models/model_store.py

@@ -2,10 +2,11 @@
 
 from collections import UserDict
 from dataclasses import dataclass, field
-from typing import Dict
+from typing import Dict, Type
 
 from . import SyncId
 from .model import Model
+from .special_models import FilteredMembers
 
 
 @dataclass(frozen=True)
@@ -23,7 +24,16 @@ class ModelStore(UserDict):
     def __missing__(self, key: SyncId) -> Model:
         """When accessing a non-existent model, create and return it."""
 
-        model          = Model(sync_id=key)
+        is_tuple = isinstance(key, tuple)
+
+        model: Model
+
+        if is_tuple and len(key) == 3 and key[2] == "filtered_members":
+            model = FilteredMembers(user_id=key[0], room_id=key[1])
+        else:
+            model = Model(sync_id=key)
+        print( key, model)
+
         self.data[key] = model
         return model
 
@@ -35,3 +45,10 @@ class ModelStore(UserDict):
             type(self).__name__,
             "\n    ".join(sorted(str(v) for v in self.values())),
         )
+
+
+    async def ensure_exists_from_qml(self, sync_id: SyncId) -> None:
+        if isinstance(sync_id, list):  # QML can't pass tuples
+            sync_id = tuple(sync_id)
+
+        self[sync_id]  # will call __missing__ if needed

src/backend/models/special_models.py

@@ -37,3 +37,16 @@ class MatchingAccounts(ModelFilter):
             (r for r in self.all_rooms.values() if r.for_account == item.id),
             False,
         )
+
+
+class FilteredMembers(FieldSubstringFilter):
+    def __init__(self, user_id: str, room_id: str) -> None:
+        self.user_id = user_id
+        self.room_id = room_id
+        sync_id      = (user_id, room_id, "filtered_members")
+
+        super().__init__(sync_id=sync_id, fields=("display_name",))
+
+
+    def accept_source(self, source: Model) -> bool:
+        return source.sync_id == (self.user_id, self.room_id, "members")