Flask: login session times out too soon

问题:

While editing a record, if there is a long wait of let say a few minutes (getting coffee) and then coming back to press the save (POST), I get redirected to the main page to login instead and the data is lost.

It seems the flask-login session expires too fast.

I did some research and came across this.

from flask import session, app

session.permanent = True

Is this the proper way to go? But even when I try this I get this exception:

  File "/Users/kave/workspace/F11A/src/application/__init__.py", line 14, in <module>
    session.permanent = True
  File "/Users/kave/workspace/F11A/src/lib/werkzeug/local.py", line 355, in <lambda>
    __setattr__ = lambda x, n, v: setattr(x._get_current_object(), n, v)
  File "/Users/kave/workspace/F11A/src/lib/werkzeug/local.py", line 297, in _get_current_object
    return self.__local()
  File "/Users/kave/workspace/F11A/src/lib/flask/globals.py", line 20, in _lookup_req_object
    raise RuntimeError('working outside of request context')
RuntimeError: working outside of request context

回答1:

Just in case someone else will have this question. I suppose Hooman already got answer.

Won`t work

views.py

from flask import session
from datetime import timedelta

session.permanent = True
app.permanent_session_lifetime = timedelta(minutes=30) 

Will work

from flask import session
from datetime import timedelta

@app.route('/home', methods=['GET', 'POST'])
def show_work():
    session.permanent = True
    app.permanent_session_lifetime = timedelta(minutes=30)
    form = MyForm(request.form)
    return render_template('home.html', form = form)

session must be used inside the request.

回答2:

If you try to access the session object like this it won't work.

As the error message says, flask.session can only be used from within a request context, which won't exist at that point. You should only use it from within a route.