X-Git-Url: https://plomlompom.com/repos/foo.html?a=blobdiff_plain;f=plomtask%2Fdb.py;h=deeb748de0b427b1ff2f999e58713d3cee4e7807;hb=6ec09c59e388711c43d9eba787c65ff8f60b9ce1;hp=1753da43cee71ca2204bbbdfd27c69aa52bd93fe;hpb=7b6b8d0b93b1d4dd85152e49e7105aacc647327c;p=plomtask diff --git a/plomtask/db.py b/plomtask/db.py index 1753da4..deeb748 100644 --- a/plomtask/db.py +++ b/plomtask/db.py @@ -4,7 +4,7 @@ from os.path import isfile from difflib import Differ from sqlite3 import connect as sql_connect, Cursor, Row from typing import Any, Self, TypeVar, Generic -from plomtask.exceptions import HandledException +from plomtask.exceptions import HandledException, NotFoundException PATH_DB_SCHEMA = 'scripts/init.sql' EXPECTED_DB_VERSION = 0 @@ -102,7 +102,8 @@ class DatabaseConnection: return [row[0] for row in self.exec(f'SELECT {column} FROM {table_name}')] - def delete_where(self, table_name: str, key: str, target: int) -> None: + def delete_where(self, table_name: str, key: str, + target: int | str) -> None: """Delete from table where key == target.""" self.exec(f'DELETE FROM {table_name} WHERE {key} = ?', (target,)) @@ -123,51 +124,11 @@ class BaseModel(Generic[BaseModelId]): id_: None | BaseModelId cache_: dict[BaseModelId, Self] - @classmethod - def from_table_row(cls: type[BaseModelInstance], - # pylint: disable=unused-argument - db_conn: DatabaseConnection, - row: Row | list[Any]) -> BaseModelInstance: - """Make from DB row, write to DB cache.""" - obj = cls(*row) - obj.cache() - return obj - - @classmethod - def _by_id(cls, - db_conn: DatabaseConnection, - 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_) - if obj: - from_cache = True - else: - for row in db_conn.row_where(cls.table_name, 'id', id_): - obj = cls.from_table_row(db_conn, row) - obj.cache() - break - return obj, from_cache - - def set_int_id(self, id_: int | None) -> None: - """Set id_ if >= 1 or None, else fail.""" - if (id_ is not None) and id_ < 1: + def __init__(self, id_: BaseModelId | None) -> None: + if isinstance(id_, int) and id_ < 1: msg = f'illegal {self.__class__.__name__} ID, must be >=1: {id_}' raise HandledException(msg) - self.id_ = id_ # type: ignore[assignment] - - def save_core(self, db_conn: DatabaseConnection, - update_with_lastrowid: bool = True) -> None: - """Write bare-bones self (sans connected items), ensuring self.id_.""" - values = tuple([self.id_] + [getattr(self, key) - for key in self.to_save]) - q_marks = DatabaseConnection.q_marks_from_values(values) - table_name = self.table_name - cursor = db_conn.exec(f'REPLACE INTO {table_name} VALUES {q_marks}', - values) - if update_with_lastrowid: - self.id_ = cursor.lastrowid # type: ignore[assignment] - self.cache() + self.id_ = id_ @classmethod def get_cached(cls: type[BaseModelInstance], @@ -181,6 +142,19 @@ class BaseModel(Generic[BaseModelId]): return obj return None + @classmethod + def empty_cache(cls) -> None: + """Empty class's cache.""" + cls.cache_ = {} + + @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_ + def cache(self) -> None: """Update object in class's cache.""" if self.id_ is None: @@ -196,9 +170,42 @@ class BaseModel(Generic[BaseModelId]): del cache[self.id_] @classmethod - def empty_cache(cls) -> None: - """Empty class's cache.""" - cls.cache_ = {} + def from_table_row(cls: type[BaseModelInstance], + # pylint: disable=unused-argument + db_conn: DatabaseConnection, + row: Row | list[Any]) -> BaseModelInstance: + """Make from DB row, write to DB cache.""" + obj = cls(*row) + obj.cache() + return obj + + @classmethod + def _by_id(cls, db_conn: DatabaseConnection, + id_: BaseModelId) -> Self | None: + """Return instance found by ID, or None, and if from cache or not.""" + obj = cls.get_cached(id_) + if not obj: + for row in db_conn.row_where(cls.table_name, 'id', id_): + obj = cls.from_table_row(db_conn, row) + obj.cache() + break + return obj + + @classmethod + def by_id(cls, db_conn: DatabaseConnection, + id_: BaseModelId | None, + # pylint: disable=unused-argument + create: bool = False) -> Self: + """Retrieve by id_, on failure throw NotFoundException.""" + obj = None + if id_ is not None: + obj = cls._by_id(db_conn, id_) + if obj: + return obj + if create: + obj = cls(id_) + return obj + raise NotFoundException(f'found no object of ID {id_}') @classmethod def all(cls: type[BaseModelInstance], @@ -211,15 +218,26 @@ class BaseModel(Generic[BaseModelId]): 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] + item = cls.by_id(db_conn, id_) + assert item.id_ is not None 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_ + def save_core(self, db_conn: DatabaseConnection, + update_with_lastrowid: bool = True) -> None: + """Write bare-bones self (sans connected items), ensuring self.id_.""" + values = tuple([self.id_] + [getattr(self, key) + for key in self.to_save]) + q_marks = DatabaseConnection.q_marks_from_values(values) + table_name = self.table_name + cursor = db_conn.exec(f'REPLACE INTO {table_name} VALUES {q_marks}', + values) + if update_with_lastrowid: + self.id_ = cursor.lastrowid # type: ignore[assignment] + self.cache() + + def remove(self, db_conn: DatabaseConnection) -> None: + """Remove from DB.""" + assert isinstance(self.id_, int | str) + self.uncache() + db_conn.delete_where(self.table_name, 'id', self.id_)