set headers for all requests in tornado

Question

I'm setting headers for my requests this way:

class ContactInfoHandler(tornado.web.RequestHandler):
    def set_default_headers(self):
        print "setting headers!!!"
        self.set_header("Access-Control-Allow-Origin", "*")
        self.set_header("Access-Control-Allow-Headers", "x-requested-with")
        self.set_header('Access-Control-Allow-Methods', 'POST, GET, OPTIONS')

    def get(self, *args, **kwargs):
        self.write('something')

I have to do it for all of my handlers, Is there a way to do it one in whole my Tornado project?

Answer 1

You can write a handler that is inherited from tornado.web.RequestHandler, then all handlers used as an API can be inherited from this handler. Here is the example below.

from tornado.web import RequestHandler

class BaseHandler(RequestHandler):
    def get(self, *args, **kwargs):
        self.write("say something")

    def set_default_headers(self, *args, **kwargs):
        self.set_header("Access-Control-Allow-Origin", "*")
        self.set_header("Access-Control-Allow-Headers", "x-requested-with")
        self.set_header("Access-Control-Allow-Methods", "POST, GET, OPTIONS")

As you have done this step, you can totally inherit what BaseHandler can do by writing handlers inherited from BaseHandler.

class ContactInfoHandler(BaseHandler):
    def get(self, *args, **kwargs):
        self.write("something")

class TestInfoHandler(BaseHandler):
    def post(self, *args, **kwargs):
        self.write("test result is here")