def _wrap_func(*args, **kwargs):
self = args[0]
session = sessionmaker(bind=self.engine, expire_on_commit=False)
# new session. no connections are in use.
self.session = session()
try:
# execute transaction statements.
res = func(*args, **kwargs)
# commit. The pending changes above
# are flushed via flush(), the Transaction
# is committed, the Connection object closed
# and discarded, the underlying DBAPI connection
# returned to the connection pool.
self.session.commit()
except Exception as err:
LOGGER.critical(err)
# on rollback, the same closure of state
# as that of commit proceeds.
self.session.rollback()
raise
finally:
# close the Session. This will expunge any remaining
# objects as well as reset any existing SessionTransaction
# state. Neither of these steps are usually essential.
# However, if the commit() or rollback() itself experienced
# an unanticipated internal failure (such as due to a mis-behaved
# user-defined event handler), .close() will ensure that
# invalid state is removed.
self.session.close()
return res
async def on_command_error(self, ctx, error):
if isinstance(error, commands.NoPrivateMessage):
await ctx.author.send(
'This command cannot be used in private messages.')
elif isinstance(error, commands.DisabledCommand):
await ctx.author.send(
'Sorry. This command is disabled and cannot be used.')
elif isinstance(error, commands.CommandInvokeError):
LOGGER.critical(f'In {ctx.command.qualified_name}:')
traceback.print_tb(error.original.__traceback__)
LOGGER.critical(
f'{error.original.__class__.__name__}: {error.original}')
elif isinstance(error, commands.MissingRequiredArgument):
await ctx.author.send(
'Sorry. This command is not how this command works, !help <command_name> to display usage'
)
else:
LOGGER.critical(error)