[Python-Dev] new httplib?

[Greg Stein]

On Thu, 17 Feb 2000, Fred L. Drake, Jr. wrote:
> Greg Stein writes:
>  > Pipelining is very important... it is once of the big advances in HTTP/1.1
>  > (well, the advance is really the "chunked" transfer encoding which
>  > *allows* pipelining to occur more often).
> 
>   You should be able to pipeline requests even if responses don't use
> chunking;

Not in all cases. You can pipeline only if the server sends a
Content-Length: header or uses chunking. There are a few other conditions
(look at the httplib.HTTPResponse constructor in my httplib), but the
Content-Length/chunking is the major point.

> if I parse the first HTML page while still receiving, I
> should be able to request non-cached images or other dependencies
> before the first HTML is completely received.  This allows the server
> to locate the resources while still waiting for me finish pulling the
> first response off the network.  It improves the possibility of
> scheduling resource location at the server (possibly important if
> there's a dynamic backend) as well as avoiding establishing new TCP
> connections.

This would be nice, but my httplib currently enforces consumption before a
new request. I do not recall the specific reasons why, but I imagine it
would be possible to change it.

[ today: you could certainly use a second connection object to improve
  client response, with the corresponding impact on the server ]

>   (Yes, some of this can be done with keep-alive stuff, but I don't
> know that httplib supports that at all.)

My httplib deals with the keep-alive header, when applicable (you are
supposed to use Connection: in HTTP/1.1; it only looks at keep-alive if
you aren't using 1.1).

Cheers,
-g

-- 
Greg Stein, http://www.lyra.org/