Re: encode/decode support for base64url

On Tue, Jul 29, 2025 at 3:25 PM Daniel Gustafsson <daniel@yesql.se> wrote:

> > On 12 Jul 2025, at 21:40, David E. Wheeler <david@justatheory.com>
> wrote:
>
> > Thank you! This looks great. The attached revision makes a a couple of
> minor changes:
>
> I also had a look at this today and agree that it looks pretty close to
> being
> done, and a feature we IMHO would like to have.


Thanks for having a look Daniel!


>
>
The attached version also adds a commit message, tweaks the documentation
> along
> with a few small changes to error message handling etc.
>

In the doc snippet

> The base64url alphabet use '-' instead of '+' and '_' instead of '/' and
also omits the '=' padding character.

Should be

> The base64url alphabet use*s* '-' instead of '+' and '_' instead of '/'*,
*and also omits the '=' padding character.

I'd also add a comma before "and also"


> The base64 code this extends is the RFC 2045 variant while base64url is
> based
> on base64 from RFC 3548 (obsoleted by RFC 4648).  AFAICT this is not a
> problem
> here but has anyone else verified this?
>

I don't see how this can be a problem in practice.
The conversions are straightforward,
and the codepath used with url=true is a new one and doesn't change past
behavior.