I see a great analogy between GA and Piwik implementation of custom variables: why does Piwik not allow custom variables with scope ‘visitor’ ?
yes it does. scope is visit. see details here: http://piwik.org/docs/javascript-tracking/#toc-custom-variables Basically, the visit scope in custom variables records the data for the duration of the visit (30 minutes after the last action).
Thank you Adrian but this is not what I thought.
As you know GA offers 3 kinds of scope in custom variables: visit, page and visitor. The main difference, just like in Piwik, is about the cookie duration (actually the first two scopes in GA are not cookies but this is another story) which for scope “visitor” is set at 24 months.
I think everyone agrees that tracking a “visit” is not the same as tracking a “visitor” so having 3 scopes as in GA makes sense to me.
Reading the docs it seems Piwik opted for not implementing the “visitor” scope, I would like to know if there was some rationale behind this or it simply is a feature could be added in next releases.
Another doubt I have is that Piwik “visit” scope could be some way transformed into the GA “visitor” equivalent but I can not see how at the moment.
Sorry I misunderstood your original question. You are right there is no Visitor Scope, and I did not see plans to add it in Trac. Matt commented last year there were no plans: http://forum.piwik.org/read.php?2,82455[/url]. My only thought is if you need it right away, you can set a cookie separately in a users browser and read it from $_COOKIE array or you can contact [url=http://piwik.org/consulting/]http://piwik.org/consulting/
if you have a really good use case, and can wait, I suggest you submit it as a feature request at http://dev.piwik.org
Thanks Adrian, that was very kind of you.