11 Mar
2024
11 Mar
'24
5:41 a.m.
On 10/03/2024 17.27, Jonas Schäfer wrote:
Dear community,
it's been a while I spoke up here.
I would like to discuss the removal of the following part-sentence from
XEP-0030 (in Final status!):
> every entity MUST support at least the
> 'http://jabber.org/protocol/disco#info' feature
I agree that this is a wart of the specification, but personally, I am
not sure if the its worth fixing it. That said, I do not have a strong
opinion on that. However, I want to point out that…
Announcing that feature is redundant: An entity which
replies with a properly
constructed `<query xmlns="http://jabber.org/protocol/disco#info"/>`
element
is bound to (and has always been bound to) have implemented XEP-0030 to the
best of its knowledge.
As this is a Final(!) status XEP, here is my estimate of the impact this
change has:
- Implementations which required the presence of this feature on the
receiving side would now become non-compliant: They might assume
that the remote entity did not really support XEP-0030 and fail with
an error.
Such implementations would need to be adapted in order to be able to
interoperate with implementations which follow a revised version of
XEP-0030.
I don't see any other impact.
...there is another impact regarding the caps cache: the footprint of
the caps cache would increase, at least during the period where old
versions announce the feature, while the updated implementation may not.
Furthermore, implementations that persist the caps cache would end up
with more-or-less useless entries (which will eventually be pushed out
of the cache).
That itself is probably not a big deal, but it nicely demonstrates that
it is often hard to understand the full impact of a change.
Again, I do not favor removing it, nor do I want to keep it. But
personally, I feel like there is not much to gained by fixing this.
- Florian