Better HTTPS support in (web client)

["Ludovic Courtès" <ludo@gnu.org>]

Hello Guilers!

I’ve pushed a ‘wip-https-client’ branch that contains improvements for
HTTPS support in (web client) that I’d like to be part of Guile 3:

  https://git.savannah.gnu.org/cgit/guile.git/log/?h=wip-https-client

In a nutshell:

  • $https_proxy support and a ‘current-https-proxy’ parameter;

  • better TLS alert handling;

  • verification of server certificates (!).

You can test it with a program as simple as:

  (use-modules (web client))

  (call-with-values
      (lambda ()
        (http-get "https://guix.gnu.org"))
    pk)

You can test how expired certificates are handled with:

  guix environment --ad-hoc libfaketime -- \
     faketime 2022-01-01 ./meta/guile /tmp/https.scm

To check whether $https_proxy is honored, try:

  https_proxy=http://localhost:8118 strace -e connect \
    ./meta/guile /tmp/https.scm

(I have Privoxy running as a proxy on that port.)

Feedback welcome!

Ludo’.