Some HTTP 2.0 questions

Hi everyone,

I recently reviewed the HTTP 2.0 draft. There are three things I expected
to see that weren't immediately obvious how to achieve. Apologies if there
have already been long discussions on these - feel free to point me at the
archives if that is the case.

(1) Canceling an HTTP request (e.g. if the client decides it no longer
needs a requested resource). This is a pain to do with HTTP1.x, requiring
the connection to be closed, losing all pipelined requests and incurring a
new TCP connection establishment delay. I assume one could close a stream
in HTTP2.0, canceling all requests on that stream. Does this mean that for
individual control of HTTP requests one must ensure each response is on its
own stream ? How does the client ensure that ?

(2) Receiver modification of stream priority. The client may have
(changing) opinions about the relative priority of resources. The
specification allows a sender of a stream to set its priority, but I didn't
immediately see how the receiver could request priority changes. [Flow
control seems to be a slightly different thing].

(3) Modification of HTTP requests. The client may wish to change some
fields of an HTTP request. Actually the only one I can think of right now
is Range. For example of the client decides it does not need the whole of
the originally requested range it would be more efficient to modify the
Range than to wait until the required data is received and cancel the
request.

Thanks in advance for any pointers on these. If they are new features
requiring more detailed use-cases I can provide those.
...Mark