coredns/middleware/file/reload.go
Miek Gieben e49ca86ce4 cleanup: go vet and golint run (#736)
* cleanup: go vet and golint run

Various cleanups trickered by go vet and golint.

* Fix tests and lowercase all errors

Lowercase all errors, some tests in kubernetes use errors from
kubernetes which do start with a capital letter.
2017-06-14 09:37:10 -07:00

72 lines
1.5 KiB
Go

package file
import (
"log"
"os"
"path"
"github.com/fsnotify/fsnotify"
)
// Reload reloads a zone when it is changed on disk. If z.NoRoload is true, no reloading will be done.
func (z *Zone) Reload() error {
if z.NoReload {
return nil
}
watcher, err := fsnotify.NewWatcher()
if err != nil {
return err
}
err = watcher.Add(path.Dir(z.file))
if err != nil {
return err
}
go func() {
// TODO(miek): needs to be killed on reload.
for {
select {
case event := <-watcher.Events:
if path.Clean(event.Name) == z.file {
reader, err := os.Open(z.file)
if err != nil {
log.Printf("[ERROR] Failed to open `%s' for `%s': %v", z.file, z.origin, err)
continue
}
serial := z.SOASerialIfDefined()
zone, err := Parse(reader, z.origin, z.file, serial)
if err != nil {
log.Printf("[WARNING] Parsing zone `%s': %v", z.origin, err)
continue
}
// copy elements we need
z.reloadMu.Lock()
z.Apex = zone.Apex
z.Tree = zone.Tree
z.reloadMu.Unlock()
log.Printf("[INFO] Successfully reloaded zone `%s'", z.origin)
z.Notify()
}
case <-z.ReloadShutdown:
watcher.Close()
return
}
}
}()
return nil
}
// SOASerialIfDefined returns the SOA's serial if the zone has a SOA record in the Apex, or
// -1 otherwise.
func (z *Zone) SOASerialIfDefined() int64 {
z.reloadMu.Lock()
defer z.reloadMu.Unlock()
if z.Apex.SOA != nil {
return int64(z.Apex.SOA.Serial)
}
return -1
}