Re: [Patch] Support HTTP/2 in HTTP client

[Derek Upham]

Okay, I figured it out.  In that particular chunk of code I was 
calling out to Curl to do the heavy lifting: “(run/port (curl 
--silent --head ,source-url))”.  Curl negotiates HTTP/2 and dumps 
the header information:

 HTTP/2 200 
 date: Tue, 07 Apr 2020 14:22:37 GMT
 content-type: audio/mpeg
 content-length: 31411830

The code then passed the response port to the existing 
“read-response” function in the web/response module, to turn this 
text into data objects.

That means this isn’t a “support HTTP/2 connections” change, it’s 
just a “support parsing HTTP/2 responses” change.

However, sometime during all of this I figured out how to get the 
system-installed extensions working with my personal build of 
Guile, so the TLS extension now works and I can cut Curl out of 
this code and just use “http-head”.  We can drop this patch.

Thanks,

Derek

Derek Upham <address@hidden> writes:

> I made this particular tweak because Guile 2.2’s HTTP/1.1 client 
> requests were getting back an HTTP/2 response from a podcast 
> server, and choking.  (The use of Google’s URL was just an 
> example to show the format of the HTTP response header.)   Let’s 
> drop the 
> patch for now.  I’ll try disabling it locally and see whether I 
> can still reproduce it.  Given the amount of redirects that 
> media 
> website backends do, it’s possible that I’ll never come across 
> the problem again.
>
> Derek
>
> Tristan Colgate <address@hidden> writes:
>
> > http/2 is a substantially different protocol, it will take
> > considerable effort to support it, guile's client should only 
> > be
> > offering http/1.1 to the server.
> >
> > On Tue, 31 Mar 2020 at 15:49, Derek Upham 
> > <address@hidden> wrote:
> > > Companies like Google now respond to HTTP requests with HTTP 
> > > 2.
> > > For example:
> > >
> > >   curl --silent --head https://www.google.com
> > >
> > > returns the first line
> > >
> > >   HTTP/2 200
> > >
> > > The Guile HTTP client code expects a “HTTP/x.y” structure, and
> > > treats this as an error.  This patch recognizes and handles
> > > “HTTP/2” on input and output.  HTTP version numbers don’t
> > > proliferate quickly, so the code uses a brute force approach 
> > > for
> > > now.
> > >
> > >
> > > Derek
> > >
> > > --
> > > Derek Upham
> > > address@hidden


--
Derek Upham
address@hidden