def dbwrap(func):

"""Wrap a function in an idomatic SQL transaction. The wrapped function should take a cursor as its first argument; other arguments will be preserved. """ def new_func(conn, *args, **kwargs):

cursor = conn.cursor() try:

cursor.execute("BEGIN") retval = func(cursor, *args, **kwargs) cursor.execute("COMMIT")
except:
cursor.execute("ROLLBACK") raise
finally:
cursor.close()

return retval

# Tidy up the help()-visible docstrings to be nice new_func.__name__ = func.__name__ new_func.__doc__ = func.__doc__

return new_func

@dbwrap def do_something(cursor, val1=1, val2=2):

"""Do that database thing.""" cursor.execute("SELECT %s, %s", (val1, val2)) return cursor.fetchall()
class SomeClass?(object):
def __init__(self):
conn = MySQLdb?.connect(db='test') self.instance_var = SomeClass?.get_stuff(conn) print self.instance_var conn.close()

@staticmethod @dbwrap def get_stuff(cursor):

"""Load something meaningful from the database.""" cursor.execute("SELECT 'blah'") return cursor.fetchall()[0]?[0]?
if '__main__' == __name__:

conn = MySQLdb?.connect(db='test') print do_something(conn) print do_something(conn, 3, 4) print do_something(conn, 5) print do_something(conn, val2=6) #help(do_something)

s = SomeClass?() #help(s)