X-Git-Url: https://plomlompom.com/repos/berlin_corona.txt?a=blobdiff_plain;f=plomtask%2Fdb.py;h=a47dff15917651940483afe83f41152399bedf7f;hb=fa05073a6ebaf46e8f72bec10a3dc03021ce704c;hp=b5461a507e9612e2593643e6d6e198779e2fc456;hpb=eff89a3ebc0b3bf5b340b0ebd2b32fa136d8f640;p=plomtask diff --git a/plomtask/db.py b/plomtask/db.py index b5461a5..a47dff1 100644 --- a/plomtask/db.py +++ b/plomtask/db.py @@ -8,7 +8,7 @@ from typing import Any, Self, TypeVar, Generic from plomtask.exceptions import HandledException, NotFoundException from plomtask.dating import valid_date -EXPECTED_DB_VERSION = 4 +EXPECTED_DB_VERSION = 5 MIGRATIONS_DIR = 'migrations' FILENAME_DB_SCHEMA = f'init_{EXPECTED_DB_VERSION}.sql' PATH_DB_SCHEMA = f'{MIGRATIONS_DIR}/{FILENAME_DB_SCHEMA}' @@ -18,8 +18,9 @@ class UnmigratedDbException(HandledException): """To identify case of unmigrated DB file.""" -class DatabaseFile: # pylint: disable=too-few-public-methods +class DatabaseFile: """Represents the sqlite3 database's file.""" + # pylint: disable=too-few-public-methods def __init__(self, path: str) -> None: self.path = path @@ -38,7 +39,7 @@ class DatabaseFile: # pylint: disable=too-few-public-methods def migrate(cls, path: str) -> DatabaseFile: """Apply migrations from_version to EXPECTED_DB_VERSION.""" migrations = cls._available_migrations() - from_version = cls.get_version_of_db(path) + from_version = cls._get_version_of_db(path) migrations_todo = migrations[from_version+1:] for j, filename in enumerate(migrations_todo): with sql_connect(path) as conn: @@ -54,7 +55,7 @@ class DatabaseFile: # pylint: disable=too-few-public-methods """Check file exists, and is of proper DB version and schema.""" if not isfile(self.path): raise NotFoundException - if self.user_version != EXPECTED_DB_VERSION: + if self._user_version != EXPECTED_DB_VERSION: raise UnmigratedDbException() self._validate_schema() @@ -86,7 +87,7 @@ class DatabaseFile: # pylint: disable=too-few-public-methods return migrations_list @staticmethod - def get_version_of_db(path: str) -> int: + def _get_version_of_db(path: str) -> int: """Get DB user_version, fail if outside expected range.""" sql_for_db_version = 'PRAGMA user_version' with sql_connect(path) as conn: @@ -99,9 +100,11 @@ class DatabaseFile: # pylint: disable=too-few-public-methods return db_version @property - def user_version(self) -> int: + def _user_version(self) -> int: """Get DB user_version.""" - return self.__class__.get_version_of_db(self.path) + # pylint: disable=protected-access + # (since we remain within class) + return self.__class__._get_version_of_db(self.path) def _validate_schema(self) -> None: """Compare found schema with what's stored at PATH_DB_SCHEMA.""" @@ -156,8 +159,7 @@ class DatabaseConnection: """A single connection to the database.""" def __init__(self, db_file: DatabaseFile) -> None: - self.file = db_file - self.conn = sql_connect(self.file.path) + self.conn = sql_connect(db_file.path) def commit(self) -> None: """Commit SQL transaction.""" @@ -167,18 +169,28 @@ class DatabaseConnection: """Add commands to SQL transaction.""" return self.conn.execute(code, inputs) + def exec_on_vals(self, code: str, inputs: tuple[Any, ...]) -> Cursor: + """Wrapper around .exec appending adequate " (?, …)" to code.""" + q_marks_from_values = '(' + ','.join(['?'] * len(inputs)) + ')' + return self.exec(f'{code} {q_marks_from_values}', inputs) + def close(self) -> None: """Close DB connection.""" self.conn.close() def rewrite_relations(self, table_name: str, key: str, target: int | str, - rows: list[list[Any]]) -> None: - """Rewrite relations in table_name to target, with rows values.""" + rows: list[list[Any]], key_index: int = 0) -> None: + # pylint: disable=too-many-arguments + """Rewrite relations in table_name to target, with rows values. + + Note that single rows are expected without the column and value + identified by key and target, which are inserted inside the function + at key_index. + """ self.delete_where(table_name, key, target) for row in rows: - values = tuple([target] + row) - q_marks = self.__class__.q_marks_from_values(values) - self.exec(f'INSERT INTO {table_name} VALUES {q_marks}', values) + values = tuple(row[:key_index] + [target] + row[key_index:]) + self.exec_on_vals(f'INSERT INTO {table_name} VALUES', values) def row_where(self, table_name: str, key: str, target: int | str) -> list[Row]: @@ -214,11 +226,6 @@ class DatabaseConnection: """Delete from table where key == target.""" self.exec(f'DELETE FROM {table_name} WHERE {key} = ?', (target,)) - @staticmethod - def q_marks_from_values(values: tuple[Any]) -> str: - """Return placeholder to insert values into SQL code.""" - return '(' + ','.join(['?'] * len(values)) + ')' - BaseModelId = TypeVar('BaseModelId', int, str) BaseModelInstance = TypeVar('BaseModelInstance', bound='BaseModel[Any]') @@ -229,7 +236,7 @@ class BaseModel(Generic[BaseModelId]): table_name = '' to_save: list[str] = [] to_save_versioned: list[str] = [] - to_save_relations: list[tuple[str, str, str]] = [] + to_save_relations: list[tuple[str, str, str, int]] = [] id_: None | BaseModelId cache_: dict[BaseModelId, Self] to_search: list[str] = [] @@ -238,16 +245,24 @@ class BaseModel(Generic[BaseModelId]): if isinstance(id_, int) and id_ < 1: msg = f'illegal {self.__class__.__name__} ID, must be >=1: {id_}' raise HandledException(msg) + if isinstance(id_, str) and "" == id_: + msg = f'illegal {self.__class__.__name__} ID, must be non-empty' + raise HandledException(msg) self.id_ = id_ + def __hash__(self) -> int: + hashable = [self.id_] + [getattr(self, name) for name in self.to_save] + for definition in self.to_save_relations: + attr = getattr(self, definition[2]) + hashable += [tuple(rel.id_ for rel in attr)] + for name in self.to_save_versioned: + hashable += [hash(getattr(self, name))] + return hash(tuple(hashable)) + def __eq__(self, other: object) -> bool: if not isinstance(other, self.__class__): return False - to_hash_me = tuple([self.id_] + - [getattr(self, name) for name in self.to_save]) - to_hash_other = tuple([other.id_] + - [getattr(other, name) for name in other.to_save]) - return hash(to_hash_me) == hash(to_hash_other) + return hash(self) == hash(other) def __lt__(self, other: Any) -> bool: if not isinstance(other, self.__class__): @@ -362,7 +377,7 @@ class BaseModel(Generic[BaseModelId]): date_col: str = 'day' ) -> tuple[list[BaseModelInstance], str, str]: - """Return list of Days in database within (open) date_range interval. + """Return list of items in database within (open) date_range interval. If no range values provided, defaults them to 'yesterday' and 'tomorrow'. Knows to properly interpret these and 'today' as value. @@ -411,20 +426,19 @@ class BaseModel(Generic[BaseModelId]): """ 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) + cursor = db_conn.exec_on_vals(f'REPLACE INTO {table_name} VALUES', + values) if not isinstance(self.id_, str): self.id_ = cursor.lastrowid # type: ignore[assignment] self.cache() for attr_name in self.to_save_versioned: getattr(self, attr_name).save(db_conn) - for table, column, attr_name in self.to_save_relations: + for table, column, attr_name, key_index in self.to_save_relations: assert isinstance(self.id_, (int, str)) db_conn.rewrite_relations(table, column, self.id_, [[i.id_] for i - in getattr(self, attr_name)]) + in getattr(self, attr_name)], key_index) def remove(self, db_conn: DatabaseConnection) -> None: """Remove from DB and cache, including dependencies.""" @@ -432,7 +446,7 @@ class BaseModel(Generic[BaseModelId]): raise HandledException('cannot remove unsaved item') for attr_name in self.to_save_versioned: getattr(self, attr_name).remove(db_conn) - for table, column, attr_name in self.to_save_relations: + for table, column, attr_name, _ in self.to_save_relations: db_conn.delete_where(table, column, self.id_) self.uncache() db_conn.delete_where(self.table_name, 'id', self.id_)