req.method == "PURGE" causes loop and "too many requests" error.

[wfsmith]

This if statement in vcl_purge req.method == "PURGE" causes my setup to loop and error out with "Too many requests" error when I send PURGE request. Counterintuitively, when I change it to req.method != "PURGE", PURGE works and everything is fine.

My setup is based on varnish-4.0-configuration-templates so my setup had req.method != "PURGE" from back when you first made this change based on this Github Issue.

But then it was changed back to req.method == "PURGE" in this commit.

Then in varnish-5.0-configuration-templates, it goes back to req.method != "PURGE".

This carries through in 6.0 default.vcl until this patch changes it again back to req.method == "PURGE"

I am just curious to understand these changes. For me, req.method != "PURGE" seems wrong logically but it's the only change that fixes my PURGE issue.

Note that I use NGINX as the backend and also for TLS termination so I am not sure if this is what causes this to appear like a bug to me.

Cheers