func WaitPrefixEvents(c *clientv3.Client, prefix string, rev int64, evs []mvccpb.Event_EventType) (*clientv3.Event, error) {
wc := c.Watch(context.Background(), prefix, clientv3.WithPrefix(), clientv3.WithRev(rev))
if wc == nil {
return nil, ErrNoWatcher
}
return waitEvents(wc, evs), nil
}
// WaitEvents waits on a key until it observes the given events and returns the final one.
func WaitEvents(c *clientv3.Client, key string, rev int64, evs []storagepb.Event_EventType) (*storagepb.Event, error) {
wc := c.Watch(context.Background(), key, clientv3.WithRev(rev))
if wc == nil {
return nil, ErrNoWatcher
}
return waitEvents(wc, evs), nil
}
func waitUpdate(ctx context.Context, client *v3.Client, key string, opts ...v3.OpOption) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wresp, ok := <-client.Watch(cctx, key, opts...)
if !ok {
return ctx.Err()
}
return wresp.Err()
}
// snapshotToStdout streams a snapshot over stdout
func snapshotToStdout(c *clientv3.Client) {
// must explicitly fetch first revision since no retry on stdout
wr := <-c.Watch(context.TODO(), "", clientv3.WithPrefix(), clientv3.WithRev(1))
if wr.Err() == nil {
wr.CompactRevision = 1
}
if rev := snapshot(os.Stdout, c, wr.CompactRevision+1); rev != 0 {
err := fmt.Errorf("snapshot interrupted by compaction %v", rev)
ExitWithError(ExitInterrupted, err)
}
os.Stdout.Sync()
}
func waitDelete(ctx context.Context, client *v3.Client, key string, rev int64) error {
cctx, cancel := context.WithCancel(ctx)
defer cancel()
wch := client.Watch(cctx, key, v3.WithRev(rev))
for wr := range wch {
for _, ev := range wr.Events {
if ev.Type == storagepb.DELETE {
return nil
}
}
}
if err := ctx.Err(); err != nil {
return err
}
return fmt.Errorf("lost watcher waiting for delete")
}
func getWatchChan(c *clientv3.Client, args []string) (clientv3.WatchChan, error) {
if len(args) < 1 || len(args) > 2 {
return nil, fmt.Errorf("bad number of arguments")
}
key := args[0]
opts := []clientv3.OpOption{clientv3.WithRev(watchRev)}
if len(args) == 2 {
if watchPrefix {
return nil, fmt.Errorf("`range_end` and `--prefix` are mutually exclusive")
}
opts = append(opts, clientv3.WithRange(args[1]))
}
if watchPrefix {
opts = append(opts, clientv3.WithPrefix())
}
if watchPrevKey {
opts = append(opts, clientv3.WithPrevKV())
}
return c.Watch(context.TODO(), key, opts...), nil
}
func etcdMon_v3(prefix string, c3 *clientv3.Client, bus chan fileChangeEvent, startRevision int64) {
key, option := prefixToKeyOption(prefix)
ch := c3.Watch(context.Background(), key, option, clientv3.WithRev(startRevision))
for chEvent := range ch {
for _, event := range chEvent.Events {
fileEvent := fileChangeEvent{
Path: string(event.Kv.Key),
Content: event.Kv.Value,
}
switch event.Type {
case mvccpb.PUT:
bus <- fileEvent
case mvccpb.DELETE:
fileEvent.IsRemoved = true
bus <- fileEvent
default:
log.Println("etcdMon_v3 undefined event type: ", event.Type)
}
}
}
close(bus)
}
func main() {
flag.Parse()
if config.Version {
fmt.Printf("skydns server version: %s\n", server.Version)
os.Exit(0)
}
machines := strings.Split(machine, ",")
var clientptr *etcdv3.Client
var err error
var clientv3 etcdv3.Client
var clientv2 etcd.KeysAPI
if config.Etcd3 {
clientptr, err = newEtcdV3Client(machines, tlspem, tlskey, cacert)
clientv3 = *clientptr
} else {
clientv2, err = newEtcdV2Client(machines, tlspem, tlskey, cacert, username, password)
}
if err != nil {
panic(err)
}
if nameserver != "" {
for _, hostPort := range strings.Split(nameserver, ",") {
if err := validateHostPort(hostPort); err != nil {
log.Fatalf("skydns: nameserver is invalid: %s", err)
}
config.Nameservers = append(config.Nameservers, hostPort)
}
}
if err := validateHostPort(config.DnsAddr); err != nil {
log.Fatalf("skydns: addr is invalid: %s", err)
}
if config.Etcd3 {
if err := loadEtcdV3Config(clientv3, config); err != nil {
log.Fatalf("skydns: %s", err)
}
} else {
if err := loadEtcdV2Config(clientv2, config); err != nil {
log.Fatalf("skydns: %s", err)
}
}
if err := server.SetDefaults(config); err != nil {
log.Fatalf("skydns: defaults could not be set from /etc/resolv.conf: %v", err)
}
if config.Local != "" {
config.Local = dns.Fqdn(config.Local)
}
var backend server.Backend
if config.Etcd3 {
backend = backendetcdv3.NewBackendv3(clientv3, ctx, &backendetcdv3.Config{
Ttl: config.Ttl,
Priority: config.Priority,
})
} else {
backend = backendetcd.NewBackend(clientv2, ctx, &backendetcd.Config{
Ttl: config.Ttl,
Priority: config.Priority,
})
}
s := server.New(backend, config)
if stub {
s.UpdateStubZones()
go func() {
duration := 1 * time.Second
if config.Etcd3 {
var watcher etcdv3.WatchChan
watcher = clientv3.Watch(ctx, msg.Path(config.Domain)+"/dns/stub/", etcdv3.WithPrefix())
for wresp := range watcher {
if wresp.Err() != nil {
log.Printf("skydns: stubzone update failed, sleeping %s + ~3s", duration)
time.Sleep(duration + (time.Duration(rand.Float32() * 3e9)))
duration *= 2
if duration > 32*time.Second {
duration = 32 * time.Second
}
} else {
s.UpdateStubZones()
log.Printf("skydns: stubzone update")
duration = 1 * time.Second //reset
}
}
} else {
var watcher etcd.Watcher
watcher = clientv2.Watcher(msg.Path(config.Domain)+"/dns/stub/", &etcd.WatcherOptions{AfterIndex: 0, Recursive: true})
for {
_, err := watcher.Next(ctx)
if err != nil {
//
log.Printf("skydns: stubzone update failed, sleeping %s + ~3s", duration)
time.Sleep(duration + (time.Duration(rand.Float32() * 3e9))) // Add some random.
duration *= 2
if duration > 32*time.Second {
duration = 32 * time.Second
}
} else {
s.UpdateStubZones()
log.Printf("skydns: stubzone update")
duration = 1 * time.Second // reset
}
}
}
}()
}
if err := metrics.Metrics(); err != nil {
log.Fatalf("skydns: %s", err)
} else {
log.Printf("skydns: metrics enabled on :%s%s", metrics.Port, metrics.Path)
}
if err := s.Run(); err != nil {
log.Fatalf("skydns: %s", err)
}
}