Une bonne tête WWW-Authenticate pour le fournisseur OAuth

Question

Dans le OAuth 1.0 spec il est suggéré de répondre à la suivant en-tête WWW-Authenticate:

WWW-Authenticate: OAuth realm="http://server.example.com/"

Est-il approprié d'ajouter d'autres données d'information à cet en-tête? Dans le cas d'une demande d'une ressource protégée échoue, serait-il raisonnable d'inclure des informations sur les raisons? Tels que:

WWW-Authenticate: OAuth realm="http://server.example.com/", access token invalid

Ou est-ce contraire à l'objet de l'en-tête de réponse?

Answer 1

Sounds a little dubious to me. The WWW-Authenticate header is specified by an RFC, which would seem to forbid the example you've given. The OAuth spec says that you can include other WWW-Authenticate fields as defined by the RFC, not that you can just tack arbitrary strings onto the end of it. I would avoid it, unless there is a defined field that you could twist to your purposes.

Answer 2

Note for anyone just stumbling across this: The OAuth 2.0 bearer token spec adds "error", "error_description", and "error_uri" attributes to the "WWW-Authenticate" header for reporting additional error information, and it specifies when they should and shouldn't be used.

E.g.:

 HTTP/1.1 401 Unauthorized
 WWW-Authenticate: Bearer realm="example",
                   error="invalid_token",
                   error_description="The access token expired"

Answer 3

It's against the spec to do that, and if it wasn't it would probably be something like :

realm="http://server.example.com", oauth_error="access token invalid"

I'd recommend using the response body for things like this, or maybe a X-OAuth-Error header.