[spec] IRIs, IDNs, and all that international jazz

[cage]

On Tue, Dec 22, 2020 at 04:13:06PM +0100, Solderpunk wrote:
> Hi folks,

Hi!

[...]

> Feedback welcome, especially if I've overlooked anything, which is
> certainly possible.  What I'd be most interested in hearing, at this
> point, is client authors letting me know whether the standard library
> in the language their client is implemented in can straightforwardly:

The language i written my client with is Common lisp

> 1. Parse and relativise [absolutize] URLs with non-ASCII characters (so, yes, okay,
>    technically not URLs at all, you know what I mean) in paths and/or
>    domains?

The language has no concept of URI; IRI or even URL in the standard library.

I am aware of two free/libre libraries but in my experience both have problems.
I ended writing my custom parser for URI and IRI, that probably is broken as well. ;-)

> 2. Transform back and forth between URIs and IRIs?

Before making a  request I punycode the domain  and percent-encode the
query and fragment (should also percent-encode the path?).

Anyway there is a third party  free library to do percent-encoding and
decoding.

> 3. Do DNS lookups of IDNs without them being punycoded first?  You can
>    test this with räksmörgås.josefsson.org.

There  is library  in CL  that do  punycoding, i  wrapped a  C library
(libidn2) to do the same instead. I can resolve the domain above! :)

Bye!
C.