How do I return HTTP error code without default template in Tornado?

Question

I am currently using the following to raise a HTTP bad request:

raise tornado.web.HTTPError(400)

which returns a html output:

&         


        

Answer 1

It's better to use the standard interface and define your custom message on the HTTPError.

raise tornado.web.HTTPError(status_code=code, log_message=custom_msg)

You can then parse the error in your RequestHandler and check for the message:

class CustomHandler(tornado.web.RequestHandler):
    def write_error(self, status_code, **kwargs):
        err_cls, err, traceback = kwargs['exc_info']
        if err.log_message and err.log_message.startswith(custom_msg):
            self.write("
Here be dragons
")