moment/src/backend/models/model_store.py

58 lines
1.7 KiB
Python

# SPDX-License-Identifier: LGPL-3.0-or-later
from collections import UserDict
from dataclasses import dataclass, field
from typing import Dict
from . import SyncId
from .model import Model
from .special_models import AllRooms, FilteredMembers, MatchingAccounts
@dataclass(frozen=True)
class ModelStore(UserDict):
"""Dict of sync ID keys and `Model` values.
The dict keys must be the sync ID of `Model` values.
If a non-existent key is accessed, a corresponding `Model` will be
created, put into the internal `data` dict and returned.
"""
data: Dict[SyncId, Model] = field(default_factory=dict)
def __missing__(self, key: SyncId) -> Model:
"""When accessing a non-existent model, create and return it."""
is_tuple = isinstance(key, tuple)
model: Model
if key == "all_rooms":
model = AllRooms(self["accounts"])
elif key == "matching_accounts":
model = MatchingAccounts(self["all_rooms"])
elif 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) # type: ignore
self.data[key] = model
return model
def __str__(self) -> str:
"""Provide a nice overview of stored models when `print()` called."""
return "%s(\n %s\n)" % (
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