X-Git-Url: https://plomlompom.com/repos/%7B%7B%20web_path%20%7D%7D/decks/%7B%7Bdeck_id%7D%7D/cards/%7B%7Bcard_id%7D%7D/static/git-logo.png?a=blobdiff_plain;f=plomtask%2Fdb.py;h=1753da43cee71ca2204bbbdfd27c69aa52bd93fe;hb=7b6b8d0b93b1d4dd85152e49e7105aacc647327c;hp=bf2b79f758b313525816581620a792330fdbd9a2;hpb=23c7ff7f9833ff5b0e547c19a4ad85325a5d3400;p=plomtask diff --git a/plomtask/db.py b/plomtask/db.py index bf2b79f..1753da4 100644 --- a/plomtask/db.py +++ b/plomtask/db.py @@ -112,22 +112,22 @@ class DatabaseConnection: return '(' + ','.join(['?'] * len(values)) + ')' -X = TypeVar('X', int, str) -T = TypeVar('T', bound='BaseModel[Any]') +BaseModelId = TypeVar('BaseModelId', int, str) +BaseModelInstance = TypeVar('BaseModelInstance', bound='BaseModel[Any]') -class BaseModel(Generic[X]): +class BaseModel(Generic[BaseModelId]): """Template for most of the models we use/derive from the DB.""" table_name = '' to_save: list[str] = [] - id_: None | X - cache_: dict[X, Self] = {} + id_: None | BaseModelId + cache_: dict[BaseModelId, Self] @classmethod - def from_table_row(cls: type[T], + def from_table_row(cls: type[BaseModelInstance], # pylint: disable=unused-argument db_conn: DatabaseConnection, - row: Row | list[Any]) -> T: + row: Row | list[Any]) -> BaseModelInstance: """Make from DB row, write to DB cache.""" obj = cls(*row) obj.cache() @@ -136,7 +136,7 @@ class BaseModel(Generic[X]): @classmethod def _by_id(cls, db_conn: DatabaseConnection, - id_: X) -> tuple[Self | None, bool]: + id_: BaseModelId) -> tuple[Self | None, bool]: """Return instance found by ID, or None, and if from cache or not.""" from_cache = False obj = cls.get_cached(id_) @@ -170,11 +170,13 @@ class BaseModel(Generic[X]): self.cache() @classmethod - def get_cached(cls: type[T], id_: X) -> T | None: + def get_cached(cls: type[BaseModelInstance], + id_: BaseModelId) -> BaseModelInstance | None: """Get object of id_ from class's cache, or None if not found.""" # pylint: disable=consider-iterating-dictionary - if id_ in cls.cache_.keys(): - obj = cls.cache_[id_] + cache = cls.get_cache() + if id_ in cache.keys(): + obj = cache[id_] assert isinstance(obj, cls) return obj return None @@ -183,15 +185,41 @@ class BaseModel(Generic[X]): """Update object in class's cache.""" if self.id_ is None: raise HandledException('Cannot cache object without ID.') - self.__class__.cache_[self.id_] = self + cache = self.__class__.get_cache() + cache[self.id_] = self def uncache(self) -> None: """Remove self from cache.""" if self.id_ is None: raise HandledException('Cannot un-cache object without ID.') - del self.__class__.cache_[self.id_] + cache = self.__class__.get_cache() + del cache[self.id_] @classmethod def empty_cache(cls) -> None: """Empty class's cache.""" cls.cache_ = {} + + @classmethod + def all(cls: type[BaseModelInstance], + db_conn: DatabaseConnection) -> list[BaseModelInstance]: + """Collect all objects of class.""" + items: dict[BaseModelId, BaseModelInstance] = {} + for k, v in cls.get_cache().items(): + assert isinstance(v, cls) + items[k] = v + already_recorded = items.keys() + for id_ in db_conn.column_all(cls.table_name, 'id'): + if id_ not in already_recorded: + # pylint: disable=no-member + item = cls.by_id(db_conn, id_) # type: ignore[attr-defined] + items[item.id_] = item + return list(items.values()) + + @classmethod + def get_cache(cls: type[BaseModelInstance]) -> dict[Any, BaseModel[Any]]: + """Get cache dictionary, create it if not yet existing.""" + if not hasattr(cls, 'cache_'): + d: dict[Any, BaseModel[Any]] = {} + cls.cache_ = d + return cls.cache_