烧瓶对象没有属性app_context

Question

I'm trying to send emails periodically with flask mail, but I'm stuck with this error: Flask object has no attribute app_context

def mail_periodic():
    print "sending mail at " +time.ctime()

    app = current_app._get_current_object()

    msg = Message("no-reply: Avantgarde.Rentals",
                  sender="avantgarde.rentals.noreply@gmail.com",
                  )

    msg.add_recipient('aladinne.k@gmail.com')

    msg.body = 'Email periodic '
    mail2 = Mail(app)
    with app.app_context():
        mail2.send(msg)
    print"email sent "

threading.Timer(5, mail_periodic).start()



@app.route('/startcronemailing')
def startcronemailing():
    try:
        mail_periodic()
    except Exception, exception:
            return exception.message
    return "crone mailing started"

the exception that i got :

Exception in thread Thread-3:
Traceback (most recent call last):
  File "C:\Python27\lib\threading.py", line 801, in __bootstrap_inner
    self.run()
  File "C:\Python27\lib\threading.py", line 1073, in run
    self.function(*self.args, **self.kwargs)
  File "app.py", line 113, in mail_periodic
    host_link='http://' + request.host,
  File "C:\Python27\lib\site-packages\werkzeug\local.py", line 336, in __getattr__
    return getattr(self._get_current_object(), name)
  File "C:\Python27\lib\site-packages\werkzeug\local.py", line 295, in _get_current_object
    return self.__local()
  File "C:\Python27\lib\site-packages\flask\globals.py", line 19, in _lookup_object
    raise RuntimeError('working outside of request context')
RuntimeError: working outside of request context

please note that even if i use another mailing service like sendgrid i got the same error

Answer 1

You have to pass app instance as args. If you use current_app._get_current_object() to get app instance inside target function, you will not get the right app in another thread. For example:

from threading import Thread

from flask import current_app
from flask_mail import Message

from bluelog.extensions import mail

def _send_async_mail(app, message):  # target function
    with app.app_context():
        mail.send(message)

def send_async_mail(subject, to, html):
    app = current_app._get_current_object()  # get the real app instance
    message = Message(subject, recipients=[to], html=html)
    thr = Thread(target=_send_async_mail, args=[app, message])  # pass app
    thr.start()
    return thr