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pythontornado

tornado: how to add www if user doesn't type

I'm using the Tornado with python to build a web server. I want to allow users not to type www.

For example, if user types example.com to visit my web page, I want to add www for user. In other words, if user types example.com in his browser and type "Enter", a www will be inserted automatically in front of example.com.

This is my code for now:

application.add_handlers(r"^(www).*", [(r"/$", IndexHandler)])

With the code above, if user visits www.example.com, the class IndexHandler will get the request and render the index page (self.render('/index.html')).

Then I've tried like this:

application.add_handlers(r"^(example).*", [(r"/$", RedirectionHandler)])


class RedirectionHandler(tornado.web.RequestHandler):
    def get(self):
        self.redirect('www.example.com')

Well, it doesn't work because self.redirect gives me example.com/www.example.com

Solution

  • Do

    seft.redirect('http://www.example.com')

    In general in any language when you redirect plain text, the system thinks it's a relative url and tries to append/complete the url with the existing hostname in the already typed url (here example.com).

    Putting http(s):// at the beginning tells that the address is absolute, so you rewrite all the address from scratch.