Support DoNotTrack (DNT)

[Paweł Krawczyk]

DoNotTrack (DNT) is a HTTP request header, a proposed W3C standard ​http://www.w3.org/TR/tracking-dnt/#dnt-header-field which is used by the browsers to communicate user's preference on server-side profiling or tacking. There is a number of 3rd party Django middlewares that add support of this header, but it would be nice if it was supported natively.

The implementation is very simple: just expose a dnt variable in the request object, depending on the value of DNT header in HTTP request. It takes 3 values: 1 if DNT header was 1 (explicit preference not to be tracked), 0 if DNT was 0 (explicit preference to be tracked) or None if there was no DNT header (no preference).

Sample middleware that does it is here: ​https://github.com/kravietz/django-security/blob/master/security/middleware.py#L67

[Tim Graham]

Thanks for the suggestion. I've raised the idea on the ​django-developers mailling list for discussion.

[Tim Graham]

Consensus from the mailing list:

Alex: "I would say no: this does _so_ little, and it's completely implementable outside of Django. Moreover, adding the middleware doesn't change any behavior, you still have to do a bunch of work in your app to actually implement the not-tracking logic."

Aymeric: "Indeed I’m afraid that people will believe that the middleware makes them compliant, while it doesn’t. Worse, it will echo the DNT header, implying that it’s handled correctly, even if it isn’t. "