Re: [Wish] Can a client switch tokens?

[Juliusz Chroboczek <[e-mail]>]

> what do you mean by switch/update tokens?

The client C requests a token T1.

C uses T1 to create a WHIP session:

  C->S: POST(T1) offer
  S->C: answer

An hour later, C decides to do an ICE restart.  However, T1 has expired.
There are two possible client behaviours:

1. C uses token T1 for the ICE restart, even though it has expired:

  C->S: PATCH(T1)

2. C requests a new token T2, and uses the new, unexpired token:

  C->S: PATCH(T2)

In case 1, the server needs to allow the client to use an expired token
with a WHIP session, as long as the token is identical to the one used for
creating the session.  This is easy to implement, both on the client (the
client never renews a token) and on the server (the server retains the
original token in the data structure that represents a WHIP session).

In case 2, the server needs to allow the client to use a different token
for PATCH requests than the one used during session creation.  There is
also the need to communicate to the client the information that a token
has expired.  I have no idea how to implement case 2.

Galene currently uses approach 1, it stores the token used for session
creation and allows it to be reused for PATCH even when it has expired.
Is this the intended behaviour for a WHIP client?  If it is, then I think
we need to document (possibly in an informational appendix) that a PATCH
request may use an expired token.  If it is not, then please explain the
intended behaviour.

-- Juliusz