"""SQLAlchemy util functions.""" from __future__ import annotations from collections.abc import Callable, Generator, Iterable from contextlib import contextmanager from datetime import date, datetime, timedelta import functools import logging import os import time from typing import TYPE_CHECKING, Any, TypeVar from awesomeversion import ( AwesomeVersion, AwesomeVersionException, AwesomeVersionStrategy, ) import ciso8601 from sqlalchemy import text from sqlalchemy.engine.cursor import CursorFetchStrategy from sqlalchemy.engine.row import Row from sqlalchemy.exc import OperationalError, SQLAlchemyError from sqlalchemy.ext.baked import Result from sqlalchemy.orm.query import Query from sqlalchemy.orm.session import Session from sqlalchemy.sql.lambdas import StatementLambdaElement from typing_extensions import Concatenate, ParamSpec from homeassistant.core import HomeAssistant import homeassistant.util.dt as dt_util from .const import DATA_INSTANCE, SQLITE_URL_PREFIX, SupportedDialect from .models import ( TABLE_RECORDER_RUNS, TABLE_SCHEMA_CHANGES, TABLES_TO_CHECK, RecorderRuns, process_timestamp, ) if TYPE_CHECKING: from . import Recorder _RecorderT = TypeVar("_RecorderT", bound="Recorder") _P = ParamSpec("_P") _LOGGER = logging.getLogger(__name__) RETRIES = 3 QUERY_RETRY_WAIT = 0.1 SQLITE3_POSTFIXES = ["", "-wal", "-shm"] DEFAULT_YIELD_STATES_ROWS = 32768 MIN_VERSION_MARIA_DB = AwesomeVersion("10.3.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_MARIA_DB_ROWNUM = AwesomeVersion("10.2.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_MYSQL = AwesomeVersion("8.0.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_MYSQL_ROWNUM = AwesomeVersion("5.8.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_PGSQL = AwesomeVersion("12.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_SQLITE = AwesomeVersion("3.31.0", AwesomeVersionStrategy.SIMPLEVER) MIN_VERSION_SQLITE_ROWNUM = AwesomeVersion("3.25.0", AwesomeVersionStrategy.SIMPLEVER) # This is the maximum time after the recorder ends the session # before we no longer consider startup to be a "restart" and we # should do a check on the sqlite3 database. MAX_RESTART_TIME = timedelta(minutes=10) # Retry when one of the following MySQL errors occurred: RETRYABLE_MYSQL_ERRORS = (1205, 1206, 1213) # 1205: Lock wait timeout exceeded; try restarting transaction # 1206: The total number of locks exceeds the lock table size # 1213: Deadlock found when trying to get lock; try restarting transaction FIRST_POSSIBLE_SUNDAY = 8 SUNDAY_WEEKDAY = 6 DAYS_IN_WEEK = 7 @contextmanager def session_scope( *, hass: HomeAssistant | None = None, session: Session | None = None, exception_filter: Callable[[Exception], bool] | None = None, ) -> Generator[Session, None, None]: """Provide a transactional scope around a series of operations.""" if session is None and hass is not None: session = hass.data[DATA_INSTANCE].get_session() if session is None: raise RuntimeError("Session required") need_rollback = False try: yield session if session.get_transaction(): need_rollback = True session.commit() except Exception as err: # pylint: disable=broad-except _LOGGER.error("Error executing query: %s", err) if need_rollback: session.rollback() if not exception_filter or not exception_filter(err): raise finally: session.close() def commit(session: Session, work: Any) -> bool: """Commit & retry work: Either a model or in a function.""" for _ in range(0, RETRIES): try: if callable(work): work(session) else: session.add(work) session.commit() return True except OperationalError as err: _LOGGER.error("Error executing query: %s", err) session.rollback() time.sleep(QUERY_RETRY_WAIT) return False def execute( qry: Query | Result, to_native: bool = False, validate_entity_ids: bool = True, ) -> list[Row]: """Query the database and convert the objects to HA native form. This method also retries a few times in the case of stale connections. """ for tryno in range(0, RETRIES): try: timer_start = time.perf_counter() if to_native: result = [ row for row in ( row.to_native(validate_entity_id=validate_entity_ids) for row in qry ) if row is not None ] else: result = qry.all() if _LOGGER.isEnabledFor(logging.DEBUG): elapsed = time.perf_counter() - timer_start if to_native: _LOGGER.debug( "converting %d rows to native objects took %fs", len(result), elapsed, ) else: _LOGGER.debug( "querying %d rows took %fs", len(result), elapsed, ) return result except SQLAlchemyError as err: _LOGGER.error("Error executing query: %s", err) if tryno == RETRIES - 1: raise time.sleep(QUERY_RETRY_WAIT) assert False # unreachable # pragma: no cover def execute_stmt_lambda_element( session: Session, stmt: StatementLambdaElement, start_time: datetime | None = None, end_time: datetime | None = None, yield_per: int | None = DEFAULT_YIELD_STATES_ROWS, ) -> Iterable[Row]: """Execute a StatementLambdaElement. If the time window passed is greater than one day the execution method will switch to yield_per to reduce memory pressure. It is not recommended to pass a time window when selecting non-ranged rows (ie selecting specific entities) since they are usually faster with .all(). """ executed = session.execute(stmt) use_all = not start_time or ((end_time or dt_util.utcnow()) - start_time).days <= 1 for tryno in range(0, RETRIES): try: return executed.all() if use_all else executed.yield_per(yield_per) # type: ignore[no-any-return] except SQLAlchemyError as err: _LOGGER.error("Error executing query: %s", err) if tryno == RETRIES - 1: raise time.sleep(QUERY_RETRY_WAIT) assert False # unreachable # pragma: no cover def validate_or_move_away_sqlite_database(dburl: str) -> bool: """Ensure that the database is valid or move it away.""" dbpath = dburl_to_path(dburl) if not os.path.exists(dbpath): # Database does not exist yet, this is OK return True if not validate_sqlite_database(dbpath): move_away_broken_database(dbpath) return False return True def dburl_to_path(dburl: str) -> str: """Convert the db url into a filesystem path.""" return dburl[len(SQLITE_URL_PREFIX) :] def last_run_was_recently_clean(cursor: CursorFetchStrategy) -> bool: """Verify the last recorder run was recently clean.""" cursor.execute("SELECT end FROM recorder_runs ORDER BY start DESC LIMIT 1;") end_time = cursor.fetchone() if not end_time or not end_time[0]: return False last_run_end_time = process_timestamp(dt_util.parse_datetime(end_time[0])) assert last_run_end_time is not None now = dt_util.utcnow() _LOGGER.debug("The last run ended at: %s (now: %s)", last_run_end_time, now) if last_run_end_time + MAX_RESTART_TIME < now: return False return True def basic_sanity_check(cursor: CursorFetchStrategy) -> bool: """Check tables to make sure select does not fail.""" for table in TABLES_TO_CHECK: if table in (TABLE_RECORDER_RUNS, TABLE_SCHEMA_CHANGES): cursor.execute(f"SELECT * FROM {table};") # nosec # not injection else: cursor.execute(f"SELECT * FROM {table} LIMIT 1;") # nosec # not injection return True def validate_sqlite_database(dbpath: str) -> bool: """Run a quick check on an sqlite database to see if it is corrupt.""" import sqlite3 # pylint: disable=import-outside-toplevel try: conn = sqlite3.connect(dbpath) run_checks_on_open_db(dbpath, conn.cursor()) conn.close() except sqlite3.DatabaseError: _LOGGER.exception("The database at %s is corrupt or malformed", dbpath) return False return True def run_checks_on_open_db(dbpath: str, cursor: CursorFetchStrategy) -> None: """Run checks that will generate a sqlite3 exception if there is corruption.""" sanity_check_passed = basic_sanity_check(cursor) last_run_was_clean = last_run_was_recently_clean(cursor) if sanity_check_passed and last_run_was_clean: _LOGGER.debug( "The system was restarted cleanly and passed the basic sanity check" ) return if not sanity_check_passed: _LOGGER.warning( "The database sanity check failed to validate the sqlite3 database at %s", dbpath, ) if not last_run_was_clean: _LOGGER.warning( "The system could not validate that the sqlite3 database at %s was shutdown cleanly", dbpath, ) def move_away_broken_database(dbfile: str) -> None: """Move away a broken sqlite3 database.""" isotime = dt_util.utcnow().isoformat() corrupt_postfix = f".corrupt.{isotime}" _LOGGER.error( "The system will rename the corrupt database file %s to %s in order to allow startup to proceed", dbfile, f"{dbfile}{corrupt_postfix}", ) for postfix in SQLITE3_POSTFIXES: path = f"{dbfile}{postfix}" if not os.path.exists(path): continue os.rename(path, f"{path}{corrupt_postfix}") def execute_on_connection(dbapi_connection: Any, statement: str) -> None: """Execute a single statement with a dbapi connection.""" cursor = dbapi_connection.cursor() cursor.execute(statement) cursor.close() def query_on_connection(dbapi_connection: Any, statement: str) -> Any: """Execute a single statement with a dbapi connection and return the result.""" cursor = dbapi_connection.cursor() cursor.execute(statement) result = cursor.fetchall() cursor.close() return result def _warn_unsupported_dialect(dialect_name: str) -> None: """Warn about unsupported database version.""" _LOGGER.warning( "Database %s is not supported; Home Assistant supports %s. " "Starting with Home Assistant 2022.2 this will prevent the recorder from " "starting. Please migrate your database to a supported software before then", dialect_name, "MariaDB ≥ 10.3, MySQL ≥ 8.0, PostgreSQL ≥ 12, SQLite ≥ 3.31.0", ) def _warn_unsupported_version( server_version: str, dialect_name: str, minimum_version: str ) -> None: """Warn about unsupported database version.""" _LOGGER.warning( "Version %s of %s is not supported; minimum supported version is %s. " "Starting with Home Assistant 2022.2 this will prevent the recorder from " "starting. Please upgrade your database software before then", server_version, dialect_name, minimum_version, ) def _extract_version_from_server_response( server_response: str, ) -> AwesomeVersion | None: """Attempt to extract version from server response.""" try: return AwesomeVersion( server_response, ensure_strategy=AwesomeVersionStrategy.SIMPLEVER, find_first_match=True, ) except AwesomeVersionException: return None def _datetime_or_none(value: str) -> datetime | None: """Fast version of mysqldb DateTime_or_None. https://github.com/PyMySQL/mysqlclient/blob/v2.1.0/MySQLdb/times.py#L66 """ try: return ciso8601.parse_datetime(value) except ValueError: return None def build_mysqldb_conv() -> dict: """Build a MySQLDB conv dict that uses cisco8601 to parse datetimes.""" # Late imports since we only call this if they are using mysqldb from MySQLdb.constants import ( # pylint: disable=import-outside-toplevel,import-error FIELD_TYPE, ) from MySQLdb.converters import ( # pylint: disable=import-outside-toplevel,import-error conversions, ) return {**conversions, FIELD_TYPE.DATETIME: _datetime_or_none} def setup_connection_for_dialect( instance: Recorder, dialect_name: str, dbapi_connection: Any, first_connection: bool, ) -> None: """Execute statements needed for dialect connection.""" # Returns False if the the connection needs to be setup # on the next connection, returns True if the connection # never needs to be setup again. if dialect_name == SupportedDialect.SQLITE: if first_connection: old_isolation = dbapi_connection.isolation_level dbapi_connection.isolation_level = None execute_on_connection(dbapi_connection, "PRAGMA journal_mode=WAL") dbapi_connection.isolation_level = old_isolation # WAL mode only needs to be setup once # instead of every time we open the sqlite connection # as its persistent and isn't free to call every time. result = query_on_connection(dbapi_connection, "SELECT sqlite_version()") version_string = result[0][0] version = _extract_version_from_server_response(version_string) if version and version < MIN_VERSION_SQLITE_ROWNUM: instance._db_supports_row_number = ( # pylint: disable=[protected-access] False ) if not version or version < MIN_VERSION_SQLITE: _warn_unsupported_version( version or version_string, "SQLite", MIN_VERSION_SQLITE ) # approximately 8MiB of memory execute_on_connection(dbapi_connection, "PRAGMA cache_size = -8192") # enable support for foreign keys execute_on_connection(dbapi_connection, "PRAGMA foreign_keys=ON") elif dialect_name == SupportedDialect.MYSQL: execute_on_connection(dbapi_connection, "SET session wait_timeout=28800") if first_connection: result = query_on_connection(dbapi_connection, "SELECT VERSION()") version_string = result[0][0] version = _extract_version_from_server_response(version_string) is_maria_db = "mariadb" in version_string.lower() if is_maria_db: if version and version < MIN_VERSION_MARIA_DB_ROWNUM: instance._db_supports_row_number = ( # pylint: disable=[protected-access] False ) if not version or version < MIN_VERSION_MARIA_DB: _warn_unsupported_version( version or version_string, "MariaDB", MIN_VERSION_MARIA_DB ) else: if version and version < MIN_VERSION_MYSQL_ROWNUM: instance._db_supports_row_number = ( # pylint: disable=[protected-access] False ) if not version or version < MIN_VERSION_MYSQL: _warn_unsupported_version( version or version_string, "MySQL", MIN_VERSION_MYSQL ) elif dialect_name == SupportedDialect.POSTGRESQL: if first_connection: # server_version_num was added in 2006 result = query_on_connection(dbapi_connection, "SHOW server_version") version_string = result[0][0] version = _extract_version_from_server_response(version_string) if not version or version < MIN_VERSION_PGSQL: _warn_unsupported_version( version or version_string, "PostgreSQL", MIN_VERSION_PGSQL ) else: _warn_unsupported_dialect(dialect_name) def end_incomplete_runs(session: Session, start_time: datetime) -> None: """End any incomplete recorder runs.""" for run in session.query(RecorderRuns).filter_by(end=None): run.closed_incorrect = True run.end = start_time _LOGGER.warning( "Ended unfinished session (id=%s from %s)", run.run_id, run.start ) session.add(run) def retryable_database_job( description: str, ) -> Callable[ [Callable[Concatenate[_RecorderT, _P], bool]], Callable[Concatenate[_RecorderT, _P], bool], ]: """Try to execute a database job. The job should return True if it finished, and False if it needs to be rescheduled. """ def decorator( job: Callable[Concatenate[_RecorderT, _P], bool] ) -> Callable[Concatenate[_RecorderT, _P], bool]: @functools.wraps(job) def wrapper(instance: _RecorderT, *args: _P.args, **kwargs: _P.kwargs) -> bool: try: return job(instance, *args, **kwargs) except OperationalError as err: assert instance.engine is not None if ( instance.engine.dialect.name == SupportedDialect.MYSQL and err.orig.args[0] in RETRYABLE_MYSQL_ERRORS ): _LOGGER.info( "%s; %s not completed, retrying", err.orig.args[1], description ) time.sleep(instance.db_retry_wait) # Failed with retryable error return False _LOGGER.warning("Error executing %s: %s", description, err) # Failed with permanent error return True return wrapper return decorator def periodic_db_cleanups(instance: Recorder) -> None: """Run any database cleanups that need to happen periodically. These cleanups will happen nightly or after any purge. """ assert instance.engine is not None if instance.engine.dialect.name == SupportedDialect.SQLITE: # Execute sqlite to create a wal checkpoint and free up disk space _LOGGER.debug("WAL checkpoint") with instance.engine.connect() as connection: connection.execute(text("PRAGMA wal_checkpoint(TRUNCATE);")) @contextmanager def write_lock_db_sqlite(instance: Recorder) -> Generator[None, None, None]: """Lock database for writes.""" assert instance.engine is not None with instance.engine.connect() as connection: # Execute sqlite to create a wal checkpoint # This is optional but makes sure the backup is going to be minimal connection.execute(text("PRAGMA wal_checkpoint(TRUNCATE)")) # Create write lock _LOGGER.debug("Lock database") connection.execute(text("BEGIN IMMEDIATE;")) try: yield finally: _LOGGER.debug("Unlock database") connection.execute(text("END;")) def async_migration_in_progress(hass: HomeAssistant) -> bool: """Determine is a migration is in progress. This is a thin wrapper that allows us to change out the implementation later. """ if DATA_INSTANCE not in hass.data: return False instance: Recorder = hass.data[DATA_INSTANCE] return instance.migration_in_progress def second_sunday(year: int, month: int) -> date: """Return the datetime.date for the second sunday of a month.""" second = date(year, month, FIRST_POSSIBLE_SUNDAY) day_of_week = second.weekday() if day_of_week == SUNDAY_WEEKDAY: return second return second.replace( day=(FIRST_POSSIBLE_SUNDAY + (SUNDAY_WEEKDAY - day_of_week) % DAYS_IN_WEEK) ) def is_second_sunday(date_time: datetime) -> bool: """Check if a time is the second sunday of the month.""" return bool(second_sunday(date_time.year, date_time.month).day == date_time.day)