如何使用Tornado的self.write方法发送javascript代码段？

Question

I was trying to send a small piece of javascript to the browser, using Tornado's self.write method:

@tornado.web.asynchronous
@tornado.gen.coroutine
def post(self):
    [...]    #deal with arguments, db operation, and so on #async.

    #if _auth_flag is True, then send the alert
    if _auth_flag:
        self.write("<script>alert('Login Successfully');</script>")
        self.redirect("/")

    [...]    #other code

when I run the web app, however, no alert was executed.

MY QUESTIONG IS:

• Why this code does not work correctly?

• If the code above is not appropriate, how can I send the same alert to browser in other ways?

Answer 1

If you send a redirect, the rest of the response is ignored. You'll have to either only send a redirect and ensure that whatever JS you want appears on the following page, or only send the javascript and have the javascript assign to location.href to perform the "redirect".