[Varnish] #690: Allow for a negative grace period for internal crawler

[Varnish]

#690: Allow for a negative grace period for internal crawler
------------------------+---------------------------------------------------
 Reporter:  mikeytown2  |        Type:  enhancement
   Status:  new         |    Priority:  normal     
Milestone:              |   Component:  build      
  Version:  2.0         |    Severity:  normal     
 Keywords:  grace       |  
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Comment(by tfheen):

 Is there a particular reason why you can't just do something like:

 sub vcl_recv {
   set req.grace = 5m;
   if (req.http.user-agent == "crawler") {
     set req.grace = 0s;
   }
 }

 sub vcl_hit {
   if (req.http.user-agent == "crawler" && req.restarts == 0) {
     set obj.ttl = 0s;
     restart;
   }
 }

 In this case you can have real clients which end up fetching the object,
 I'm assuming that's not a problem, and if it is, that's fixable too.

-- 
Ticket URL: <http://www.varnish-cache.org/ticket/690#comment:1>
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