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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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26
plugin/reload/setup.go
View file

@ -1,6 +1,7 @@
package reload
import (
"fmt"
"math/rand"
"sync"
"time"
@ -17,7 +18,11 @@ func init() {
})
}
var r *reload
// the info reload is global to all application, whatever number of reloads.
// it is used to transmit data between Setup and start of the hook called 'onInstanceStartup'
// channel for QUIT is never changed in purpose.
// WARNING: this data may be unsync after an invalid attempt of reload Corefile.
var r = reload{interval: defaultInterval, usage: unused, quit: make(chan bool)}
var once sync.Once
func setup(c *caddy.Controller) error {
@ -32,19 +37,25 @@ func setup(c *caddy.Controller) error {
if len(args) > 0 {
d, err := time.ParseDuration(args[0])
if err != nil {
return err
return plugin.Error("reload", err)
}
i = d
}
if i < minInterval {
return plugin.Error("reload", fmt.Errorf("interval value must be greater or equal to %v", minInterval))
}
j := defaultJitter
if len(args) > 1 {
d, err := time.ParseDuration(args[1])
if err != nil {
return err
return plugin.Error("reload", err)
}
j = d
}
if j < minJitter {
return plugin.Error("reload", fmt.Errorf("jitter value must be greater or equal to %v", minJitter))
}
if j > i/2 {
j = i / 2
@ -53,20 +64,25 @@ func setup(c *caddy.Controller) error {
jitter := time.Duration(rand.Int63n(j.Nanoseconds()) - (j.Nanoseconds() / 2))
i = i + jitter
r = &reload{interval: i, quit: make(chan bool)}
// prepare info for next onInstanceStartup event
r.interval = i
r.usage = used
once.Do(func() {
caddy.RegisterEventHook("reload", hook)
})
// re-register on finalShutDown as the instance most-likely will be changed
c.OnFinalShutdown(func() error {
r.quit <- true
return nil
})
return nil
}
const (
minJitter = 1 * time.Second
minInterval = 2 * time.Second
defaultInterval = 30 * time.Second
defaultJitter = 15 * time.Second
)