diff options
| -rw-r--r-- | plugin/reload/README.md | 1 | ||||
| -rw-r--r-- | plugin/reload/reload.go | 33 | ||||
| -rw-r--r-- | plugin/reload/setup.go | 26 | ||||
| -rw-r--r-- | plugin/reload/setup_test.go | 12 |
4 files changed, 56 insertions, 16 deletions
diff --git a/plugin/reload/README.md b/plugin/reload/README.md index 64e5b1d93..1f7f572ad 100644 --- a/plugin/reload/README.md +++ b/plugin/reload/README.md @@ -35,6 +35,7 @@ reload [INTERVAL] [JITTER] * The plugin will check for changes every **INTERVAL**, subject to +/- the **JITTER** duration * **INTERVAL** and **JITTER** are Golang (durations)[https://golang.org/pkg/time/#ParseDuration] * Default **INTERVAL** is 30s, default **JITTER** is 15s +* Minimal value for **INTERVAL** is 2s, and for **JITTER** is 1s * If **JITTER** is more than half of **INTERVAL**, it will be set to half of **INTERVAL** ## Examples diff --git a/plugin/reload/reload.go b/plugin/reload/reload.go index e469b4526..e7031455f 100644 --- a/plugin/reload/reload.go +++ b/plugin/reload/reload.go @@ -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: diff --git a/plugin/reload/setup.go b/plugin/reload/setup.go index af6fe1334..480bd5b74 100644 --- a/plugin/reload/setup.go +++ b/plugin/reload/setup.go @@ -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 ) diff --git a/plugin/reload/setup_test.go b/plugin/reload/setup_test.go index 3c488bf2b..a647cd2a6 100644 --- a/plugin/reload/setup_test.go +++ b/plugin/reload/setup_test.go @@ -36,4 +36,16 @@ func TestSetupReload(t *testing.T) { if err := setup(c); err == nil { t.Fatalf("Expected errors, but got: %v", err) } + c = caddy.NewTestController("dns", `reload 1s`) + if err := setup(c); err == nil { + t.Fatalf("Expected errors, but got: %v", err) + } + c = caddy.NewTestController("dns", `reload 0s`) + if err := setup(c); err == nil { + t.Fatalf("Expected errors, but got: %v", err) + } + c = caddy.NewTestController("dns", `reload 3s 0.5s`) + if err := setup(c); err == nil { + t.Fatalf("Expected errors, but got: %v", err) + } } |