[Doh] Hackathon javascript client & browser issue

Tom Pusateri <pusateri@bangj.com> Sun, 18 March 2018 14:11 UTC

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From: Tom Pusateri <pusateri@bangj.com>
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Date: Sun, 18 Mar 2018 14:10:59 +0000
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Subject: [Doh] Hackathon javascript client & browser issue
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Working in the hackathon, I created a simple node javascript client to test DoH.


This works fine and then Stéphane asked if it could run in the browser. So I did this:


However, when sending a POST to a test server, I am getting a error (400) response to an initial pre-flight OPTIONS request.

According to https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS#Simple_requests

The only content types allowed for a POST are:

	• application/x-www-form-urlencoded
	• multipart/form-data
	• text/plain

so a question I have, should the DoH servers respond to a pre-flight OPTIONS method or are things working as designed because this shouldn’t be allowed to run in a browser?