Context manager for Python’s MySQLdb

Previously, MySQLdb connections were context managers.
As of this commit on 2018-12-04, however, MySQLdb connections are no longer context managers,
and users must explicitly call conn.commit() or conn.rollback(), or write their own context manager, such as the one below.


You could use something like this:

import config
import MySQLdb
import MySQLdb.cursors as mc
import _mysql_exceptions
import contextlib
DictCursor = mc.DictCursor
SSCursor = mc.SSCursor
SSDictCursor = mc.SSDictCursor
Cursor = mc.Cursor

@contextlib.contextmanager
def connection(cursorclass=Cursor,
               host=config.HOST, user=config.USER,
               passwd=config.PASS, dbname=config.MYDB,
               driver=MySQLdb):
    connection = driver.connect(
            host=host, user=user, passwd=passwd, db=dbname,
            cursorclass=cursorclass)
    try:
        yield connection
    except Exception:
        connection.rollback()
        raise
    else:
        connection.commit()
    finally:
        connection.close()

@contextlib.contextmanager
def cursor(cursorclass=Cursor, host=config.HOST, user=config.USER,
           passwd=config.PASS, dbname=config.MYDB):
    with connection(cursorclass, host, user, passwd, dbname) as conn:
        cursor = conn.cursor()
        try:
            yield cursor
        finally:
            cursor.close()


with cursor(SSDictCursor) as cur:
    print(cur)
    connection = cur.connection
    print(connection)
    sql="select * from table"
    cur.execute(sql)
    for row in cur:
        print(row)

To use it you would place config.py in your PYTHONPATH and define the HOST, USER, PASS, MYDB variables there.

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