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Plugin/RELOAD - Tune usage of var global, add limit to options (#1457)

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* tune usage of var global, add limit to options

* update readme for minimal values

* useless change to quick-off codecov

* fix msgs for min values and tune the flag for end of reload usage, with a 'maybe' option

* adding UT for min values, adding MD5 of corefile on the log
This commit is contained in:
Francois Tur 2018-02-02 13:15:56 -05:00 • committed by John Belamaric
parent 3fb07161b7
commit 2440024772
4 changed files with 56 additions and 16 deletions
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33
plugin/reload/reload.go
View file

@ -9,12 +9,15 @@ import (
)
// reload periodically checks if the Corefile has changed, and reloads if so
const (
unused = 0
maybeUsed = 1
used = 2
)
type reload struct {
instance *caddy.Instance
interval time.Duration
sum [md5.Size]byte
stopped bool
usage int
quit chan bool
}
@ -26,13 +29,14 @@ func hook(event caddy.EventName, info interface{}) error {
// if reload is removed from the Corefile, then the hook
// is still registered but setup is never called again
// so we need a flag to tell us not to reload
if r.stopped {
if r.usage == unused {
return nil
}
// this should be an instance. ok to panic if not
r.instance = info.(*caddy.Instance)
r.sum = md5.Sum(r.instance.Caddyfile().Body())
instance := info.(*caddy.Instance)
md5sum := md5.Sum(instance.Caddyfile().Body())
log.Printf("[INFO] Running configuration MD5 = %x\n", md5sum)
go func() {
tick := time.NewTicker(r.interval)
@ -40,19 +44,26 @@ func hook(event caddy.EventName, info interface{}) error {
for {
select {
case <-tick.C:
corefile, err := caddy.LoadCaddyfile(r.instance.Caddyfile().ServerType())
corefile, err := caddy.LoadCaddyfile(instance.Caddyfile().ServerType())
if err != nil {
continue
}
s := md5.Sum(corefile.Body())
if s != r.sum {
_, err := r.instance.Restart(corefile)
if s != md5sum {
// Let not try to restart with the same file, even though it is wrong.
md5sum = s
// now lets consider that plugin will not be reload, unless appear in next config file
// change status iof usage will be reset in setup if the plugin appears in config file
r.usage = maybeUsed
_, err := instance.Restart(corefile)
if err != nil {
log.Printf("[ERROR] Corefile changed but reload failed: %s\n", err)
continue
}
// we are done, this hook gets called again with new instance
r.stopped = true
// we are done, if the plugin was not set used, then it is not.
if r.usage == maybeUsed {
r.usage = unused
}
return
}
case <-r.quit: