func ExampleLease_create() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
kvc := clientv3.NewKV(cli)
lapi := clientv3.NewLease(cli)
defer lapi.Close()
// minimum lease TTL is 5-second
resp, err := lapi.Create(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
// after 5 seconds, the key 'foo' will be removed
_, err = kvc.Put(context.TODO(), "foo", "bar", clientv3.WithLease(lease.LeaseID(resp.ID)))
if err != nil {
log.Fatal(err)
}
}
func ExampleLease_keepAliveOnce() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
resp, err := cli.Grant(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar", clientv3.WithLease(clientv3.LeaseID(resp.ID)))
if err != nil {
log.Fatal(err)
}
// to renew the lease only once
_, err = cli.KeepAliveOnce(context.TODO(), clientv3.LeaseID(resp.ID))
if err != nil {
log.Fatal(err)
}
}
func ExampleMaintenance_status() {
for _, ep := range endpoints {
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{ep},
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
// resp, err := cli.Status(context.Background(), ep)
//
// or
//
mapi := clientv3.NewMaintenance(cli)
resp, err := mapi.Status(context.Background(), ep)
if err != nil {
log.Fatal(err)
}
fmt.Printf("endpoint: %s / IsLeader: %v\n", ep, resp.Header.MemberId == resp.Leader)
}
// endpoint: localhost:2379 / IsLeader: false
// endpoint: localhost:22379 / IsLeader: false
// endpoint: localhost:32379 / IsLeader: true
}
func ExampleLease_keepAlive() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
resp, err := cli.Grant(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar", clientv3.WithLease(resp.ID))
if err != nil {
log.Fatal(err)
}
// the key 'foo' will be kept forever
ch, kaerr := cli.KeepAlive(context.TODO(), resp.ID)
if kaerr != nil {
log.Fatal(kaerr)
}
ka := <-ch
fmt.Println("ttl:", ka.TTL)
// Output: ttl: 5
}
func ExampleLease_keepAliveOnce() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
resp, err := cli.Grant(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar", clientv3.WithLease(resp.ID))
if err != nil {
log.Fatal(err)
}
// to renew the lease only once
ka, kaerr := cli.KeepAliveOnce(context.TODO(), resp.ID)
if kaerr != nil {
log.Fatal(kaerr)
}
fmt.Println("ttl:", ka.TTL)
// Output: ttl: 5
}
func (c *cluster) checkCompact(rev int64) error {
if rev == 0 {
return nil
}
for _, u := range c.GRPCURLs {
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{u},
DialTimeout: 5 * time.Second,
})
if err != nil {
return fmt.Errorf("%v (endpoint %s)", err, u)
}
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
wch := cli.Watch(ctx, "\x00", clientv3.WithFromKey(), clientv3.WithRev(rev-1))
wr, ok := <-wch
cancel()
cli.Close()
if !ok {
return fmt.Errorf("watch channel terminated (endpoint %s)", u)
}
if wr.CompactRevision != rev {
return fmt.Errorf("got compact revision %v, wanted %v (endpoint %s)", wr.CompactRevision, rev, u)
}
}
return nil
}
// GetLeader returns the index of leader and error if any.
func (c *cluster) GetLeader() (int, error) {
if c.v2Only {
return 0, nil
}
for i, ep := range c.GRPCURLs {
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{ep},
DialTimeout: 5 * time.Second,
})
if err != nil {
return 0, err
}
defer cli.Close()
mapi := clientv3.NewMaintenance(cli)
resp, err := mapi.Status(context.Background(), ep)
if err != nil {
return 0, err
}
if resp.Header.MemberId == resp.Leader {
return i, nil
}
}
return 0, fmt.Errorf("no leader found")
}
func ExampleKV_getWithRev() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
presp, err := cli.Put(context.TODO(), "foo", "bar1")
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar2")
if err != nil {
log.Fatal(err)
}
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
resp, err := cli.Get(ctx, "foo", clientv3.WithRev(presp.Header.Revision))
cancel()
if err != nil {
log.Fatal(err)
}
for _, ev := range resp.Kvs {
fmt.Printf("%s : %s\n", ev.Key, ev.Value)
}
// Output: foo : bar1
}
func newETCD3Storage(c storagebackend.Config) (storage.Interface, error) {
tlsInfo := transport.TLSInfo{
CertFile: c.CertFile,
KeyFile: c.KeyFile,
CAFile: c.CAFile,
}
tlsConfig, err := tlsInfo.ClientConfig()
if err != nil {
return nil, err
}
// NOTE: Client relies on nil tlsConfig
// for non-secure connections, update the implicit variable
if len(c.CertFile) == 0 && len(c.KeyFile) == 0 && len(c.CAFile) == 0 {
tlsConfig = nil
}
cfg := clientv3.Config{
Endpoints: c.ServerList,
TLS: tlsConfig,
}
client, err := clientv3.New(cfg)
if err != nil {
return nil, err
}
etcd3.StartCompactor(context.Background(), client)
return etcd3.New(client, c.Codec, c.Prefix), nil
}
func ExampleConfig_withTLS() {
tlsInfo := transport.TLSInfo{
CertFile: "/tmp/test-certs/test-name-1.pem",
KeyFile: "/tmp/test-certs/test-name-1-key.pem",
TrustedCAFile: "/tmp/test-certs/trusted-ca.pem",
}
tlsConfig, err := tlsInfo.ClientConfig()
if err != nil {
log.Fatal(err)
}
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
TLS: tlsConfig,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close() // make sure to close the client
_, err = cli.Put(context.TODO(), "foo", "bar")
if err != nil {
log.Fatal(err)
}
}
func setRing(cfg torus.Config, r torus.Ring) error {
client, err := etcdv3.New(etcdv3.Config{Endpoints: []string{cfg.MetadataAddress}, TLS: cfg.TLS})
if err != nil {
return err
}
defer client.Close()
resp, err := client.Get(context.Background(), MkKey("meta", "the-one-ring"))
if err != nil {
return err
}
if len(resp.Kvs) == 0 {
return torus.ErrNoGlobalMetadata
}
oldr, err := ring.Unmarshal(resp.Kvs[0].Value)
if err != nil {
return err
}
if oldr.Version() != r.Version()-1 {
return torus.ErrNonSequentialRing
}
b, err := r.Marshal()
if err != nil {
return err
}
_, err = client.Put(context.Background(), MkKey("meta", "the-one-ring"), string(b))
return err
}
func newKVProxyServer(endpoints []string, t *testing.T) *kvproxyTestServer {
cfg := clientv3.Config{
Endpoints: endpoints,
DialTimeout: 5 * time.Second,
}
client, err := clientv3.New(cfg)
if err != nil {
t.Fatal(err)
}
kvp := NewKvProxy(client)
kvts := &kvproxyTestServer{
kp: kvp,
}
var opts []grpc.ServerOption
kvts.server = grpc.NewServer(opts...)
pb.RegisterKVServer(kvts.server, kvts.kp)
kvts.l, err = net.Listen("tcp", "127.0.0.1:0")
if err != nil {
t.Fatal(err)
}
go kvts.server.Serve(kvts.l)
return kvts
}
func newETCD3Storage(c storagebackend.Config) (storage.Interface, DestroyFunc, error) {
tlsInfo := transport.TLSInfo{
CertFile: c.CertFile,
KeyFile: c.KeyFile,
CAFile: c.CAFile,
}
tlsConfig, err := tlsInfo.ClientConfig()
if err != nil {
return nil, nil, err
}
// NOTE: Client relies on nil tlsConfig
// for non-secure connections, update the implicit variable
if len(c.CertFile) == 0 && len(c.KeyFile) == 0 && len(c.CAFile) == 0 {
tlsConfig = nil
}
cfg := clientv3.Config{
Endpoints: c.ServerList,
TLS: tlsConfig,
}
client, err := clientv3.New(cfg)
if err != nil {
return nil, nil, err
}
ctx, cancel := context.WithCancel(context.Background())
etcd3.StartCompactor(ctx, client)
destroyFunc := func() {
cancel()
client.Close()
}
if c.Quorum {
return etcd3.New(client, c.Codec, c.Prefix), destroyFunc, nil
}
return etcd3.NewWithNoQuorumRead(client, c.Codec, c.Prefix), destroyFunc, nil
}
func newEtcdClient(theEndpoints, certFile, keyFile, caFile string) (*clientv3.Client, error) {
// Log the etcd endpoint for debugging purposes
logger.Infof("ETCD Endpoints: %s", theEndpoints)
// ETCD config
etcdConfig := clientv3.Config{
Endpoints: strings.Split(theEndpoints, ","),
DialTimeout: dialTimeout,
}
// Optionally, configure TLS transport
if certFile != "" && keyFile != "" && caFile != "" {
// Load client cert
tlsInfo := transport.TLSInfo{
CertFile: certFile,
KeyFile: keyFile,
TrustedCAFile: caFile,
}
// Setup HTTPS client
tlsConfig, err := tlsInfo.ClientConfig()
if err != nil {
return nil, err
}
// Add TLS config
etcdConfig.TLS = tlsConfig
}
// ETCD client
return clientv3.New(etcdConfig)
}
func main() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: []string{"127.0.0.1"},
DialTimeout: 5 * time.Second,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
_, err = cli.Put(context.TODO(), "foo", "bar")
if err != nil {
log.Fatal(err)
}
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
resp, err := cli.Get(ctx, "foo")
cancel()
if err != nil {
log.Fatal(err)
}
for _, ev := range resp.Kvs {
fmt.Printf("%s : %s\n", ev.Key, ev.Value)
}
}
func ExampleKV_putErrorHandling() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
_, err = cli.Put(ctx, "", "sample_value")
cancel()
if err != nil {
switch err {
case context.Canceled:
fmt.Printf("ctx is canceled by another routine: %v\n", err)
case context.DeadlineExceeded:
fmt.Printf("ctx is attached with a deadline is exceeded: %v\n", err)
case rpctypes.ErrEmptyKey:
fmt.Printf("client-side error: %v\n", err)
default:
fmt.Printf("bad cluster endpoints, which are not etcd servers: %v\n", err)
}
}
// Output: client-side error: etcdserver: key is not provided
}
func ExampleKV_delete() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
defer cancel()
// count keys about to be deleted
gresp, err := cli.Get(ctx, "key", clientv3.WithPrefix())
if err != nil {
log.Fatal(err)
}
// delete the keys
dresp, err := cli.Delete(ctx, "key", clientv3.WithPrefix())
if err != nil {
log.Fatal(err)
}
fmt.Println("Deleted all keys:", int64(len(gresp.Kvs)) == dresp.Deleted)
// Output:
// Deleted all keys: true
}
// TestKVGetOneEndpointDown ensures a client can connect and get if one endpoint is down
func TestKVPutOneEndpointDown(t *testing.T) {
defer testutil.AfterTest(t)
clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
defer clus.Terminate(t)
// get endpoint list
eps := make([]string, 3)
for i := range eps {
eps[i] = clus.Members[i].GRPCAddr()
}
// make a dead node
clus.Members[rand.Intn(len(eps))].Stop(t)
// try to connect with dead node in the endpoint list
cfg := clientv3.Config{Endpoints: eps, DialTimeout: 1 * time.Second}
cli, err := clientv3.New(cfg)
if err != nil {
t.Fatal(err)
}
defer cli.Close()
ctx, cancel := context.WithTimeout(context.TODO(), 3*time.Second)
if _, err := cli.Get(ctx, "abc", clientv3.WithSerializable()); err != nil {
t.Fatal(err)
}
cancel()
}
// TestDialSetEndpoints ensures SetEndpoints can replace unavailable endpoints with available ones.
func TestDialSetEndpoints(t *testing.T) {
defer testutil.AfterTest(t)
clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
defer clus.Terminate(t)
// get endpoint list
eps := make([]string, 3)
for i := range eps {
eps[i] = clus.Members[i].GRPCAddr()
}
toKill := rand.Intn(len(eps))
cfg := clientv3.Config{Endpoints: []string{eps[toKill]}, DialTimeout: 1 * time.Second}
cli, err := clientv3.New(cfg)
if err != nil {
t.Fatal(err)
}
defer cli.Close()
// make a dead node
clus.Members[toKill].Stop(t)
clus.WaitLeader(t)
// update client with available endpoints
cli.SetEndpoints(eps[(toKill+1)%3])
ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
if _, err = cli.Get(ctx, "foo", clientv3.WithSerializable()); err != nil {
t.Fatal(err)
}
cancel()
}
func ExampleKV_getSortedPrefix() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
kvc := clientv3.NewKV(cli)
for i := range make([]int, 3) {
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
_, err = kvc.Put(ctx, fmt.Sprintf("key_%d", i), "value")
cancel()
if err != nil {
log.Fatal(err)
}
}
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
resp, err := kvc.Get(ctx, "key", clientv3.WithPrefix(), clientv3.WithSort(clientv3.SortByKey, clientv3.SortDescend))
cancel()
if err != nil {
log.Fatal(err)
}
for _, ev := range resp.Kvs {
fmt.Printf("%s : %s\n", ev.Key, ev.Value)
}
// key_2 : value
// key_1 : value
// key_0 : value
}
func newEtcdMetadata(cfg torus.Config) (torus.MetadataService, error) {
uuid, err := metadata.MakeOrGetUUID(cfg.DataDir)
if err != nil {
return nil, err
}
v3cfg := etcdv3.Config{Endpoints: []string{cfg.MetadataAddress}}
client, err := etcdv3.New(v3cfg)
if err != nil {
return nil, err
}
e := &Etcd{
cfg: cfg,
Client: client,
volumesCache: make(map[string]*models.Volume),
uuid: uuid,
}
e.etcdCtx.etcd = e
err = e.getGlobalMetadata()
if err != nil {
return nil, err
}
if err = e.watchRingUpdates(); err != nil {
return nil, err
}
return e, nil
}
func ExampleKV_compact() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
kvc := clientv3.NewKV(cli)
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
resp, err := kvc.Get(ctx, "foo")
cancel()
if err != nil {
log.Fatal(err)
}
compRev := resp.Header.Revision // specify compact revision of your choice
ctx, cancel = context.WithTimeout(context.Background(), requestTimeout)
err = kvc.Compact(ctx, compRev)
cancel()
if err != nil {
log.Fatal(err)
}
}
func ExampleKV_get() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
kvc := clientv3.NewKV(cli)
_, err = kvc.Put(context.TODO(), "foo", "bar")
if err != nil {
log.Fatal(err)
}
ctx, cancel := context.WithTimeout(context.Background(), requestTimeout)
resp, err := kvc.Get(ctx, "foo")
cancel()
if err != nil {
log.Fatal(err)
}
for _, ev := range resp.Kvs {
fmt.Printf("%s : %s\n", ev.Key, ev.Value)
}
// foo : bar
}
func mustClient(endpoint, cert, key, cacert string) *clientv3.Client {
// set tls if any one tls option set
var cfgtls *transport.TLSInfo
tls := transport.TLSInfo{}
var file string
if cert != "" {
tls.CertFile = cert
cfgtls = &tls
}
if key != "" {
tls.KeyFile = key
cfgtls = &tls
}
if cacert != "" {
tls.CAFile = file
cfgtls = &tls
}
cfg := clientv3.Config{
Endpoints: []string{endpoint},
TLS: cfgtls,
DialTimeout: 20 * time.Second,
}
client, err := clientv3.New(cfg)
if err != nil {
ExitWithError(ExitBadConnection, err)
}
return client
}
func mustCreateConn() *clientv3.Client {
endpoint := endpoints[dialTotal%len(endpoints)]
dialTotal++
cfg := clientv3.Config{Endpoints: []string{endpoint}}
if !tls.Empty() {
cfgtls, err := tls.ClientConfig()
if err != nil {
fmt.Fprintf(os.Stderr, "bad tls config: %v\n", err)
os.Exit(1)
}
cfg.TLS = cfgtls
}
if len(user) != 0 {
splitted := strings.SplitN(user, ":", 2)
if len(splitted) != 2 {
fmt.Fprintf(os.Stderr, "bad user information: %s\n", user)
os.Exit(1)
}
cfg.Username = splitted[0]
cfg.Password = splitted[1]
}
client, err := clientv3.New(cfg)
if err != nil {
fmt.Fprintf(os.Stderr, "dial error: %v\n", err)
os.Exit(1)
}
return client
}
func ExampleLease_keepAlive() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
resp, err := cli.Create(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar", clientv3.WithLease(clientv3.LeaseID(resp.ID)))
if err != nil {
log.Fatal(err)
}
// the key 'foo' will be kept forever
_, err = cli.KeepAlive(context.TODO(), clientv3.LeaseID(resp.ID))
if err != nil {
log.Fatal(err)
}
}
func ExampleLease_revoke() {
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
DialTimeout: dialTimeout,
})
if err != nil {
log.Fatal(err)
}
defer cli.Close()
resp, err := cli.Create(context.TODO(), 5)
if err != nil {
log.Fatal(err)
}
_, err = cli.Put(context.TODO(), "foo", "bar", clientv3.WithLease(clientv3.LeaseID(resp.ID)))
if err != nil {
log.Fatal(err)
}
// revoking lease expires the key attached to its lease ID
_, err = cli.Revoke(context.TODO(), clientv3.LeaseID(resp.ID))
if err != nil {
log.Fatal(err)
}
gresp, err := cli.Get(context.TODO(), "foo")
if err != nil {
log.Fatal(err)
}
fmt.Println("number of keys:", len(gresp.Kvs))
// number of keys: 0
}
func mustClient(cmd *cobra.Command) *clientv3.Client {
endpoint, err := cmd.Flags().GetString("endpoint")
if err != nil {
ExitWithError(ExitError, err)
}
// set tls if any one tls option set
var cfgtls *transport.TLSInfo
tls := transport.TLSInfo{}
if tls.CertFile, err = cmd.Flags().GetString("cert"); err == nil {
cfgtls = &tls
}
if tls.KeyFile, err = cmd.Flags().GetString("key"); err == nil {
cfgtls = &tls
}
if tls.CAFile, err = cmd.Flags().GetString("cacert"); err == nil {
cfgtls = &tls
}
cfg := clientv3.Config{
Endpoints: []string{endpoint},
TLS: cfgtls,
}
client, err := clientv3.New(cfg)
if err != nil {
ExitWithError(ExitBadConnection, err)
}
return client
}
func startGRPCProxy(cmd *cobra.Command, args []string) {
l, err := net.Listen("tcp", grpcProxyListenAddr)
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
cfg, err := newClientCfg()
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
client, err := clientv3.New(*cfg)
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
kvp := grpcproxy.NewKvProxy(client)
watchp := grpcproxy.NewWatchProxy(client)
server := grpc.NewServer()
pb.RegisterKVServer(server, kvp)
pb.RegisterWatchServer(server, watchp)
server.Serve(l)
}
func newClientV3(cfg clientv3.Config) (*clientv3.Client, error) {
c, err := clientv3.New(cfg)
if err != nil {
return nil, err
}
rpc := toGRPC(c)
c.KV = clientv3.NewKVFromKVClient(rpc.KV)
c.Watcher = clientv3.NewWatchFromWatchClient(rpc.Watch)
return c, nil
}
