[push-api] Version information in push API

The push-api currently stipulates a method whereby applications can
learn of missed messages.  This uses a number that increases with
every push message (version).

This places some constraints on the push server implementation that
are largely unnecessary when generic data transport is supported by
the API.  I think that removing version would simplify server
implementation.

Doug T also mentioned that there was an event that is fired when
messages might have been missed, presumably relying on the version
number to detect gaps.  I don't see this in the editor's draft, so
maybe this was only something in the mozilla implementation.

The drawback of making this simplification is that applications will
have to detect gaps or duplicates themselves.  If we consider the
standard comsec adversary model, in which the push server is not
trusted, this is something that application should be doing for itself
anyway.

Received on Monday, 12 May 2014 22:50:43 UTC