def _get_id(self, continue_transaction=False, action='draw'):
"""
Get the appropriate transaction id.
"""
self._cursor.execute(
'SELECT MAX(id) FROM transactions WHERE time IS NOT NULL;'
)
(max_transaction,) = self._cursor.fetchone()
if continue_transaction:
return max_transaction
timestamp = from_date(datetime.utcnow())
self._cursor.execute(
'DELETE FROM transactions WHERE time IS NULL;'
)
self._cursor.execute(
'DELETE FROM draws WHERE transaction_id > ?;',
(max_transaction,)
)
self._cursor.execute(
'INSERT INTO transactions (time, action) '
'VALUES (:timestamp, :action);',
{'timestamp': timestamp, 'action': action}
)
transaction = self._cursor.lastrowid
return transaction
def redo(self):
"""
Redo the next uncommitted transaction. Does nothing if none
exist
"""
self._cursor.execute(
'UPDATE transactions SET time=:timestamp WHERE id = ('
' SELECT MIN(id) FROM transactions WHERE time IS NULL'
');',
{'timestamp': from_date(datetime.utcnow())}
)