Passing Cookies to Drupal Backend

[Reinis Rozitis]

> I have been asked if it is possible to somehow retain cookies so that they 
> are available to the Drupal PHP code, but  not  have them used for caching 
> within Varnish.
> I could not think of a way to perform this, but thought I would ask those 
> with more experience.
> Does anyone know if this is possible?

In general yes it should be possible.

You can look for example at this article 
https://www.fastly.com/blog/vcl-cookie-monster (it's for the 3.x varnish but 
you should get the idea).

For recent 4.x varnish the filtering should be even more simple with the 
Cookie vmod 
https://github.com/varnish/varnish-modules/blob/master/docs/vmod_cookie.rst 
and maybe the variable mod to store the initial cookies (rather than the old 
way in extra headers).

rr