Golang clientv3.NewLease函数代码示例

func ExampleLease_keepAlive() {
	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()

	resp, err := lapi.Create(context.TODO(), 5)
	if err != nil {
		log.Fatal(err)
	}

	_, err = kvc.Put(context.TODO(), "foo", "bar", clientv3.WithLease(lease.LeaseID(resp.ID)))
	if err != nil {
		log.Fatal(err)
	}

	// the key 'foo' will be kept forever
	_, err = lapi.KeepAlive(context.TODO(), lease.LeaseID(resp.ID))
	if err != nil {
		log.Fatal(err)
	}
}

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 TestLeaseRevokeNewAfterClose(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 1})
	defer clus.Terminate(t)

	cli := clus.Client(0)
	le := clientv3.NewLease(cli)
	resp, err := le.Grant(context.TODO(), 5)
	if err != nil {
		t.Fatal(err)
	}
	leaseID := resp.ID

	clus.TakeClient(0)
	if err := cli.Close(); err != nil {
		t.Fatal(err)
	}

	donec := make(chan struct{})
	go func() {
		if _, err := le.Revoke(context.TODO(), leaseID); err != grpc.ErrClientConnClosing {
			t.Fatalf("expected %v, got %v", grpc.ErrClientConnClosing, err)
		}
		close(donec)
	}()
	select {
	case <-time.After(3 * time.Second):
		t.Fatal("le.Revoke took too long")
	case <-donec:
	}
}

func TestLeaseRevoke(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	kv := clientv3.NewKV(clus.RandClient())

	resp, err := lapi.Create(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	_, err = lapi.Revoke(context.Background(), lease.LeaseID(resp.ID))
	if err != nil {
		t.Errorf("failed to revoke lease %v", err)
	}

	_, err = kv.Put(context.TODO(), "foo", "bar", clientv3.WithLease(lease.LeaseID(resp.ID)))
	if err != v3rpc.ErrLeaseNotFound {
		t.Fatalf("err = %v, want %v", err, v3rpc.ErrLeaseNotFound)
	}
}

func TestLeaseKeepAlive(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())

	resp, err := lapi.Create(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	rc, kerr := lapi.KeepAlive(context.Background(), lease.LeaseID(resp.ID))
	if kerr != nil {
		t.Errorf("failed to keepalive lease %v", kerr)
	}

	kresp, ok := <-rc
	if !ok {
		t.Errorf("chan is closed, want not closed")
	}

	if kresp.ID != resp.ID {
		t.Errorf("ID = %x, want %x", kresp.ID, resp.ID)
	}

	lapi.Close()

	_, ok = <-rc
	if ok {
		t.Errorf("chan is not closed, want lease Close() closes chan")
	}
}

func TestLeaseTimeToLive(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	resp, err := lapi.Grant(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	kv := clientv3.NewKV(clus.RandClient())
	keys := []string{"foo1", "foo2"}
	for i := range keys {
		if _, err = kv.Put(context.TODO(), keys[i], "bar", clientv3.WithLease(resp.ID)); err != nil {
			t.Fatal(err)
		}
	}

	lresp, lerr := lapi.TimeToLive(context.Background(), resp.ID, clientv3.WithAttachedKeys())
	if lerr != nil {
		t.Fatal(lerr)
	}
	if lresp.ID != resp.ID {
		t.Fatalf("leaseID expected %d, got %d", resp.ID, lresp.ID)
	}
	if lresp.GrantedTTL != int64(10) {
		t.Fatalf("GrantedTTL expected %d, got %d", 10, lresp.GrantedTTL)
	}
	if lresp.TTL == 0 || lresp.TTL > lresp.GrantedTTL {
		t.Fatalf("unexpected TTL %d (granted %d)", lresp.TTL, lresp.GrantedTTL)
	}
	ks := make([]string, len(lresp.Keys))
	for i := range lresp.Keys {
		ks[i] = string(lresp.Keys[i])
	}
	sort.Strings(ks)
	if !reflect.DeepEqual(ks, keys) {
		t.Fatalf("keys expected %v, got %v", keys, ks)
	}

	lresp, lerr = lapi.TimeToLive(context.Background(), resp.ID)
	if lerr != nil {
		t.Fatal(lerr)
	}
	if len(lresp.Keys) != 0 {
		t.Fatalf("unexpected keys %+v", lresp.Keys)
	}
}

// TODO: add a client that can connect to all the members of cluster via unix sock.
// TODO: test handle more complicated failures.
func TestLeaseKeepAliveHandleFailure(t *testing.T) {
	t.Skip("test it when we have a cluster client")

	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	// TODO: change this line to get a cluster client
	lapi := clientv3.NewLease(clus.RandClient())

	resp, err := lapi.Create(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	rc, kerr := lapi.KeepAlive(context.Background(), lease.LeaseID(resp.ID))
	if kerr != nil {
		t.Errorf("failed to keepalive lease %v", kerr)
	}

	kresp := <-rc
	if kresp.ID != resp.ID {
		t.Errorf("ID = %x, want %x", kresp.ID, resp.ID)
	}

	// restart the connected member.
	clus.Members[0].Stop(t)

	select {
	case <-rc:
		t.Fatalf("unexpected keepalive")
	case <-time.After(10*time.Second/3 + 1):
	}

	// recover the member.
	clus.Members[0].Restart(t)

	kresp = <-rc
	if kresp.ID != resp.ID {
		t.Errorf("ID = %x, want %x", kresp.ID, resp.ID)
	}

	lapi.Close()

	_, ok := <-rc
	if ok {
		t.Errorf("chan is not closed, want lease Close() closes chan")
	}
}

func TestLeaseNotFoundError(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 1})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	kv := clientv3.NewKV(clus.RandClient())

	_, err := kv.Put(context.TODO(), "foo", "bar", clientv3.WithLease(clientv3.LeaseID(500)))
	if err != rpctypes.ErrLeaseNotFound {
		t.Fatalf("expected %v, got %v", rpctypes.ErrLeaseNotFound, err)
	}
}

func TestKVPut(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	kv := clientv3.NewKV(clus.RandClient())
	ctx := context.TODO()

	resp, err := lapi.Create(context.Background(), 10)
	if err != nil {
		t.Fatalf("failed to create lease %v", err)
	}

	tests := []struct {
		key, val string
		leaseID  lease.LeaseID
	}{
		{"foo", "bar", lease.NoLease},
		{"hello", "world", lease.LeaseID(resp.ID)},
	}

	for i, tt := range tests {
		if _, err := kv.Put(ctx, tt.key, tt.val, clientv3.WithLease(tt.leaseID)); err != nil {
			t.Fatalf("#%d: couldn't put %q (%v)", i, tt.key, err)
		}
		resp, err := kv.Get(ctx, tt.key)
		if err != nil {
			t.Fatalf("#%d: couldn't get key (%v)", i, err)
		}
		if len(resp.Kvs) != 1 {
			t.Fatalf("#%d: expected 1 key, got %d", i, len(resp.Kvs))
		}
		if !bytes.Equal([]byte(tt.val), resp.Kvs[0].Value) {
			t.Errorf("#%d: val = %s, want %s", i, tt.val, resp.Kvs[0].Value)
		}
		if tt.leaseID != lease.LeaseID(resp.Kvs[0].Lease) {
			t.Errorf("#%d: val = %d, want %d", i, tt.leaseID, resp.Kvs[0].Lease)
		}
	}
}

// leaseRevokeCommandFunc executes the "lease create" command.
func leaseRevokeCommandFunc(cmd *cobra.Command, args []string) {
	if len(args) != 1 {
		ExitWithError(ExitBadArgs, fmt.Errorf("lease revoke command needs 1 argument"))
	}

	id, err := strconv.ParseInt(args[0], 16, 64)
	if err != nil {
		ExitWithError(ExitBadArgs, fmt.Errorf("bad lease ID arg (%v), expecting ID in Hex", err))
	}

	c := mustClient(cmd)
	l := clientv3.NewLease(c)
	_, err = l.Revoke(context.TODO(), lease.LeaseID(id))
	if err != nil {
		fmt.Fprintf(os.Stderr, "failed to revoke lease (%v)\n", err)
		return
	}
	fmt.Printf("lease %016x revoked\n", id)
}

// leaseCreateCommandFunc executes the "lease create" command.
func leaseCreateCommandFunc(cmd *cobra.Command, args []string) {
	if len(args) != 1 {
		ExitWithError(ExitBadArgs, fmt.Errorf("lease create command needs TTL argument."))
	}

	ttl, err := strconv.ParseInt(args[0], 10, 64)
	if err != nil {
		ExitWithError(ExitBadArgs, fmt.Errorf("bad TTL (%v)", err))
	}

	c := mustClient(cmd)
	l := clientv3.NewLease(c)
	resp, err := l.Create(context.TODO(), ttl)
	if err != nil {
		fmt.Fprintf(os.Stderr, "failed to create lease (%v)\n", err)
		return
	}
	fmt.Printf("lease %016x created with TTL(%ds)\n", resp.ID, resp.TTL)
}

func TestLeaseKeepAliveOnce(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	resp, err := lapi.Create(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	_, err = lapi.KeepAliveOnce(context.Background(), lease.LeaseID(resp.ID))
	if err != nil {
		t.Errorf("failed to keepalive lease %v", err)
	}
}

func TestLeaseGrant(t *testing.T) {
	defer testutil.AfterTest(t)

	clus := integration.NewClusterV3(t, &integration.ClusterConfig{Size: 3})
	defer clus.Terminate(t)

	lapi := clientv3.NewLease(clus.RandClient())
	defer lapi.Close()

	kv := clientv3.NewKV(clus.RandClient())

	resp, err := lapi.Grant(context.Background(), 10)
	if err != nil {
		t.Errorf("failed to create lease %v", err)
	}

	_, err = kv.Put(context.TODO(), "foo", "bar", clientv3.WithLease(resp.ID))
	if err != nil {
		t.Fatalf("failed to create key with lease %v", err)
	}
}

// NewSession gets the leased session for a client.
func NewSession(client *v3.Client) (*Session, error) {
	clientSessions.mu.Lock()
	defer clientSessions.mu.Unlock()
	if s, ok := clientSessions.sessions[client]; ok {
		return s, nil
	}

	lc := v3.NewLease(client)
	resp, err := lc.Create(context.TODO(), sessionTTL)
	if err != nil {
		return nil, err
	}
	id := lease.LeaseID(resp.ID)

	ctx, cancel := context.WithCancel(context.Background())
	keepAlive, err := lc.KeepAlive(ctx, id)
	if err != nil || keepAlive == nil {
		return nil, err
	}

	donec := make(chan struct{})
	s := &Session{client: client, id: id, cancel: cancel, donec: donec}
	clientSessions.sessions[client] = s

	// keep the lease alive until client error or cancelled context
	go func() {
		defer func() {
			clientSessions.mu.Lock()
			delete(clientSessions.sessions, client)
			clientSessions.mu.Unlock()
			lc.Close()
			close(donec)
		}()
		for range keepAlive {
			// eat messages until keep alive channel closes
		}
	}()

	return s, nil
}

// leaseKeepAliveCommandFunc executes the "lease keep-alive" command.
func leaseKeepAliveCommandFunc(cmd *cobra.Command, args []string) {
	if len(args) != 1 {
		ExitWithError(ExitBadArgs, fmt.Errorf("lease keep-alive command needs lease ID as argument"))
	}

	id, err := strconv.ParseInt(args[0], 16, 64)
	if err != nil {
		ExitWithError(ExitBadArgs, fmt.Errorf("bad lease ID arg (%v), expecting ID in Hex", err))
	}

	c := mustClient(cmd)
	l := clientv3.NewLease(c)
	respc, kerr := l.KeepAlive(context.TODO(), lease.LeaseID(id))
	if kerr != nil {
		ExitWithError(ExitBadConnection, kerr)
	}

	for resp := range respc {
		fmt.Printf("lease %016x keepalived with TTL(%d)\n", resp.ID, resp.TTL)
	}
	fmt.Printf("lease %016x expired or revoked.\n", id)
}