Inconsistency in ETag handling

[jech]

Section 4.1.2:

A WHIP client sending a PATCH request for performing trickle ICE MUST
include an "If-Match" header field with the latest known entity-tag
as per [RFC9110] Section 13.1.1.

However, if the server does not support ICE restarts, then there might be no entity tag. Section 4.1.1:

it MUST generate a unique strong entity-tag identifying the
ICE session as per [RFC9110] Section 8.8.3, being OPTIONAL otherwise.

(By the way, the grammar of this last clause seems off to my untrained eyes.)

[murillo128]

The last sentence was suggested by a directorate review, so I would be prone to keep it as it is.

How about the following text?

If the WHIP session supports ICE restarts, a WHIP client sending a PATCH request for performing trickle ICE MUST
include an "If-Match" header field with the latest known entity-tag
as per [RFC9110] Section 13.1.1.

[jech]

If the WHIP session supports ICE restarts

I'm not sure. If the server supports ICE restarts and the client doesn't, then the session doesn't support ICE restarts, but sending If-Match is required.

The last sentence was suggested by a directorate review, so I would be prone to keep it as it is.

It's up to you, of course, but I believe it's grammatically incorrect.

[murillo128]

I'm not sure. If the server supports ICE restarts and the client doesn't, then the session doesn't support ICE restarts, but sending If-Match is required.

Yes, that's correct, the client always has to send the Etag

[jech]

Could you please make that explicit in the text?

[murillo128]

If the WHIP session supports ICE restarts, a WHIP client sending a PATCH request for performing trickle ICE MUST
include an "If-Match" header field with the latest known entity-tag
as per [RFC9110] Section 13.1.1.

In fact, this is wrong, as the WHIP session may also send the entity-tag even if it doesn't support ICE restarts (it is OPTIONAL).

So it should be something like:

If the WHIP session is using entity-tags for identifying the ICE sessions in explained in Section 4.1.1, a WHIP client sending a PATCH request for performing trickle ICE MUST
include an "If-Match" header field with the latest known entity-tag
as per [RFC9110] Section 13.1.1.

[jech]

Agreed.