我的学习笔记~

1 解决flask与MySQL失去连接的方法（如lost connect broken pip) 

'''解决flask与mysql失去连接的方法'''
config.py
    SQLALCHEMY_DATAbase_URI='mysql+pymysql://root:123456@127.0.0.1:3306/db_pv_cost' #配置参数
    SQLALCHEMY_TRACK_MODIFICATIONS = True #设置sqlalchemy自动跟踪数据库
    SECRET_KEY = os.environ.get('SECRET_KEY') or 'safsdfafefafafdsafefawfafes'
    SQLALCHEMY_COMMIT_ON_TEARDOWN = True  #每次请求结束都会自动commit数据库的变动
    # SQLALCHEMY_ECHO = True
    SQLALCHEMY_POOL_RECYCLE	=3500
    SQLALCHEMY_POOL_PRE_PING = True
    SQLALCHEMY_POOL_SIZE=10

#blueprint.py
my_engine = create_engine(
                            # 'mysql+pymysql://root:384adb9b100a4b19@127.0.0.1:3306/db_pv_cost',
                           Config.SQLALCHEMY_DATAbase_URI,
                           echo=False,
                           pool_pre_ping=True,
                           pool_recycle=3500,

                           poolclass=NullPool)
# 创建一个配置过的Session类
Session = sessionmaker(bind=my_engine,autocommit=True)
# 实例化一个session
session = scoped_session(Session)

'''设置teardown_request方法，每次相应后关闭连接'''
@bp.teardown_request
def teardown_request(exception):
    session.remove()       #关闭sqlalchemry链接
    db.session.remove()    #关闭flask-sqlalchemry链接