为什么在使用flask-script与模型进行交互时不需要app_context？

Question

My flask-script code is below, I read the document appcontext :

from flask_script import Manager
from app import app
from models import User
from ext import db

manager = Manager(app)
db.init_app(app)

@manager.option('-u','--username',dest='username')
@manager.option('-p','--password',dest='password')
def add_user(username,password):
    user = User(username=username, password=password)
    db.session.add(user)
    db.session.commit()
    print 'success'

why it success without a app_context.for example:

@manager.option('-u','--username',dest='username')
@manager.option('-p','--password',dest='password')
def add_user(username,password):
    with app.app_context():
        user = User(username=username, password=password)
        db.session.add(user)
        db.session.commit()
        print 'success'

Answer 1

因为烧瓶脚本在应用程序中声明，所以要维护应用程序上下文