This page documents both vmod_purge
and the older vmod_softpurge
. It is
recommended to upgrade to vmod_purge
if possible asits API is more complete.
Both vmods contain functions that offer a finer-grained control than the
purge
transition in vcl_recv
. The functions can only be called from
vcl_hit
or vcl_miss
and they should in general be used in both to
ensure that all variants of a same object are taken care of.
# make sure to block unauthorized IP addresse trying to purge
sub vcl_recv {
if (req.method == "PURGE") {
if (client.ip !~ purge_acl) {
return (synth(405));
} else {
return (hash);
}
}
}
# subroutine to kill the object (called from vcl_hit and vcl_miss)
# here, ttl and grace are zero'ed, but keep is set to one day so that the object
# must be revalidated before being sent to the client
sub my_purge {
set req.http.purged = purge.soft(ttl = 0s, grace = 0s, keep = 1d);
return (synth(200));
}
sub vcl_hit {
if (req.method == "PURGE") {
call my_purge;
}
}
sub vcl_miss {
if (req.method == "PURGE") {
call my_purge;
}
}
# we are sent here from my_purge, and we can now copy the purged header
# containing the number of purged objects to the response
sub vcl_synth {
if (req.method == "PURGE") {
set resp.http.purged = req.http.purged;
return (deliver);
}
}
INT soft(DURATION ttl = 0, DURATION grace = -1, DURATION keep = -1)
Sets the TTL, grace and keep. By default, TTL is set to 0s
with grace and keep
periods left untouched. Setting a negative value for grace or keep periods
leaves them untouched. Setting all three parameters to 0s
is equivalent to a
hard purge. It can only be called from vcl_hit
or vcl_miss
. It returns
the number of soft-purged objects.
INT hard()
This is equivalent to return(purge)
but explicitly called from vcl_hit
and
vcl_miss
. It returns the number of purged objects.
VOID softpurge()
The only function of the vmod performs a soft purge, setting the TTL of the
object to 0. It must be called both from vcl_hit
and vcl_miss
to make
sure all variants of the chosen object are reset.
softpurge.softpurge()
is functionally equivalent to purge.soft()
, making the
migration easy:
purge
instead of softpurge
;softpurge.softpurge()
calls with purge.soft()
.Both vmods are bundled directly in the varnish-plus
package.