def __init__(self, database: str, db_schema: str = 'dbo'):
assert isinstance(database, str)
assert isinstance(db_schema, str)
Logger().log.debug('DbBase Initializing.')
self._session_creator = None
self._raw_connection = None
self._database = database
self._db_schema = db_schema
def get_session_maker(self,
create_schema: bool = False,
create_tables: bool = False):
Logger().log.info(f'Accessing data session of {self._database}.')
if self._session_creator is None:
Logger().log.info(f'Creating session maker of {self._database}.')
self._session_creator, self._raw_connection = DbBase.generate_session_maker(
self.get_connection_string(), self._db_schema, create_schema,
create_tables)
try:
session = self._session_creator()
if not DbBase.check_connection(session):
error_msg = 'Database query error'
Logger().log.error(error_msg)
raise IOError(error_msg)
session.close()
except Exception as exp:
error_msg = f'Database access error {str(exp)}'
Logger().log.error(error_msg)
raise IOError(error_msg)
return self._session_creator
def generate_session_maker(conn_string: str,
schema: str,
create_schema: bool = False,
create_tables: bool = True):
try:
engine = create_engine(conn_string, convert_unicode=True)
if create_schema:
engine.execute(CreateSchema(schema))
if create_tables:
Base.metadata.create_all(engine)
session_creator = sessionmaker(bind=engine)
return session_creator, engine.raw_connection()
except Exception as exp:
error_msg = f'Database access error {str(exp)}.'
Logger().log.error(f'Database access error {str(exp)}.')
raise IOError(error_msg)
def get_raw_connection(self):
Logger().log.info(f'Accessing {self._database} raw connection.')
if self._raw_connection is None:
self.get_session_maker()
return self._raw_connection
def get_new_connection(self):
Logger().log.info(f'Accessing {self._database} new connection.')
return self.get_session_maker()()
def to_timestamp(x: str) -> pd.Timestamp:
try:
return pd.to_datetime(x)
except ParserError:
Logger().log.error('Error on %s conversion to Timestamp')
return pd.NaT
def __init__(self):
Logger().log.debug('DbDataSource Initializing.')
self._raw_connection = None
self._session_creator = None
super(DbDataSource, self).__init__('agenda')
def __init__(self):
Logger().log.debug('DbSource Initializing.')
self._raw_connection = None
self._session_creator = None
super(DbResult, self).__init__('result')