Roll the offer back when a re-INVITE cannot be sent - #3
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invite() creates the offer and applies it before handing the request to the dialog, so a dialog that refuses to send leaves that offer in place. The session stays up and every attempt after it fails earlier still, while creating its description, because the peer connection is no longer stable. The same rollback already runs when a re-INVITE is answered non-2xx. This extends it to the case where the request never reached the wire.
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Session.invitecreates the offer and applies it before handing the request to the dialog, so a dialog that refuses to send leaves that offer in place. The session stays up, and every attempt after it fails earlier still — while creating its description, because the peer connection is no longer stable. The same rollback already runs when a re-INVITE is answered non-2xx; this extends it to the case where the request never reached the wire.Read this before merging it
It changes nothing today, for two reasons, and both are worth weighing.
The rollback it calls does nothing until #1 lands.
Session.rollbackOfferresolves without effect when the session description handler implements norollbackDescription, and the web handler does not — #1 is what implements it. Merged alone, this is inert.And the desktop app never reaches this path. It has two
.invite(call sites:Inviter.invite()to place a call, anddialog.invite()to renegotiate. It does not callSession.invite()at all, so no hold or transfer in the app goes through the code this touches.It is proposed anyway because the fault is real for anyone using the library's own renegotiation, and because the app is not permanently safe from it — moving hold onto standard SIP.js renegotiation has been attempted before and reverted for an unrelated reason.
The cost, stated plainly:
invite()'s promise now rejects after the rollback settles rather than immediately, so a failure that was prompt becomes slightly later, and indefinitely later if a handler's rollback ever hangs. That is a new shape of failure on an error path, in exchange for nothing that is exercised today.Testing
The suite shows the three failures it already shows on
main, unchanged, and no others — see #2, which fixes those separately.Proposed upstream
This is an upstream bug, so the same change are proposed to onsip/SIP.js as onsip#1130. The fork ships it without waiting on that review; if upstream lands it first, this becomes a cherry-pick.