From discussion in http://forum.piwik.org/index.php?showtopic=217
Depends on: #409
On second thought, this doesn't depend on 409, but the client (piwik.js) needs to know/reconstruct the 3rd party cookie name.
We do need #408 fixed (possibly in conjunction with this ticket).
A first party cookie set by the client is sent as a URL param, eg PK_FPC (we could have a default and allow it to be set, ala cookie_name on the server).
Since first- vs third-party depends on whether Piwik is hosted on the same domain as the site being tracked, I'll refer to the current implementation as "legacy cookies".
User stories: - Legacy client, New visitor: Server sets legacy cookie - Legacy client, Returning visitor: Client sends legacy cookie. Server reuses cookie. - New client, New visitor: Client sets FPC. Server adopts FPC. - New client, Returning Visitor: Client sets FPC and deletes (expires) legacy cookie. Server reuses FPC and clears the legacy cookie if received. (ie some browsers won't delete cookie until session has ended/browser closed).
Need to add documentation re: P3P policy for IE6+.
Dependencies: - #408 allows the server to accept the client generated cookie and add it to the database. - #409 shortens the cookie to simply contain idvisitor
Rolling in the requirements of this ticket into #409