bug#22855: 24.5; `url-mime-accept-string' not set in asynchronous call

[Lars Ingebrigtsen <larsi@gnus.org>]

Bjarte Johansen <bjarte.johansen@gmail.com> writes:

>     (let ((url-debug t)
>           (url-request-method "POST")
> 	  (url-request-extra-headers
> 	    `(("Content-Type" . "application/x-www-form-urlencoded")))
>           (url-request-data
>             "query=SELECT%20%3FC%20WHERE%20%7B%5B%5D%20a%20%3FC%7D%20LIMIT%201%0A")
>           (url-mime-accept-string "text/csv"))
>       (url-retrieve "http://live.dbpedia.org/sparql/"
>                     #'(lambda (_)
>                         (message (buffer-string)))))
>
> This will sometimes return a csv file and sometimes an xml file (usually
> the first time). In *URL-DEBUG* you can see that the Accept header is
> not properly set.

The reason it sometimes work is that URL caches connections.  If you 

(setq url-http-open-connections (make-hash-table :test 'equal :size 17))

before calling, then it'll fail every time.

And the `url-mime-accept-string' variable is just not meant to be used
as an "interface" variable -- it's supposed to be a constant value.

But that really makes no sense, so I'll get fixin'.

I really dislike the `url-retrieve' "interface", where you bind a
gazillion special variables instead of passing in values explicitly.
One of these ... years...

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no