Golang ring.Ring類代碼示例

func partitionCmd(r ring.Ring, b *ring.Builder, args []string) error {
	if b != nil {
		return fmt.Errorf("cannot use partition command with a builder; generate a ring and use it on that")
	}
	if len(args) != 1 {
		return fmt.Errorf("use the syntax: partition <value>")
	}
	p, err := strconv.Atoi(args[0])
	if err != nil {
		return err
	}
	first := true
	for _, n := range r.ResponsibleNodes(uint32(p)) {
		if first {
			first = false
		} else {
			fmt.Println()
		}
		report := [][]string{
			[]string{"ID:", fmt.Sprintf("%016x", n.ID())},
			[]string{"Capacity:", fmt.Sprintf("%d", n.Capacity())},
			[]string{"Tiers:", strings.Join(n.Tiers(), "\n")},
			[]string{"Addresses:", strings.Join(n.Addresses(), "\n")},
			[]string{"Meta:", n.Meta()},
		}
		fmt.Print(brimtext.Align(report, nil))
	}
	return nil
}

func (rs *ReplValueStore) SetRing(r ring.Ring) {
	if r == nil {
		return
	}
	rs.ringLock.Lock()
	if rs.ringCachePath != "" {
		dir, name := path.Split(rs.ringCachePath)
		_ = os.MkdirAll(dir, 0755)
		fp, err := ioutil.TempFile(dir, name)
		if err != nil {
			rs.logDebug("replValueStore: error caching ring %q: %s", rs.ringCachePath, err)
		} else if err := r.Persist(fp); err != nil {
			fp.Close()
			os.Remove(fp.Name())
			rs.logDebug("replValueStore: error caching ring %q: %s", rs.ringCachePath, err)
		} else {
			fp.Close()
			if err := os.Rename(fp.Name(), rs.ringCachePath); err != nil {
				os.Remove(fp.Name())
				rs.logDebug("replValueStore: error caching ring %q: %s", rs.ringCachePath, err)
			}
		}
	}
	rs.ring = r
	var currentAddrs map[string]struct{}
	if r != nil {
		nodes := r.Nodes()
		currentAddrs = make(map[string]struct{}, len(nodes))
		for _, n := range nodes {
			currentAddrs[n.Address(rs.addressIndex)] = struct{}{}
		}
	}
	var shutdownAddrs []string
	rs.storesLock.RLock()
	for a := range rs.stores {
		if _, ok := currentAddrs[a]; !ok {
			shutdownAddrs = append(shutdownAddrs, a)
		}
	}
	rs.storesLock.RUnlock()
	if len(shutdownAddrs) > 0 {
		shutdownStores := make([]*replValueStoreAndTicketChan, len(shutdownAddrs))
		rs.storesLock.Lock()
		for i, a := range shutdownAddrs {
			shutdownStores[i] = rs.stores[a]
			rs.stores[a] = nil
		}
		rs.storesLock.Unlock()
		for i, s := range shutdownStores {
			if err := s.store.Shutdown(context.Background()); err != nil {
				rs.logDebug("replValueStore: error during shutdown of store %s: %s", shutdownAddrs[i], err)
			}
		}
	}
	rs.ringLock.Unlock()
}

func bootstrapManagedNodes(ring ring.Ring, ccport int, ctxlog *log.Entry, gopts ...grpc.DialOption) map[uint64]ManagedNode {
	nodes := ring.Nodes()
	m := make(map[uint64]ManagedNode, len(nodes))
	for _, node := range nodes {
		addr, err := ParseManagedNodeAddress(node.Address(0), ccport)
		if err != nil {
			ctxlog.WithFields(log.Fields{
				"node":    node.ID(),
				"address": node.Address(0),
			}).Info("Can't split address in node (skipped node)")
			continue
		}
		m[node.ID()], err = NewManagedNode(&ManagedNodeOpts{Address: addr, GrpcOpts: gopts})
		if err != nil {
			ctxlog.WithFields(log.Fields{
				"node":    node.ID(),
				"address": node.Address(0),
				"err":     err,
			}).Warning("Unable to bootstrap node")
		} else {
			ctxlog.WithFields(log.Fields{
				"node":    node.ID(),
				"address": node.Address(0),
			}).Debug("Added node")
		}
	}
	return m
}

func tierCmd(r ring.Ring, b *ring.Builder, args []string) error {
	var tiers [][]string
	if r == nil {
		tiers = b.Tiers()
	} else {
		tiers = r.Tiers()
	}
	report := [][]string{
		[]string{"Tier", "Existing"},
		[]string{"Level", "Values"},
	}
	reportOpts := brimtext.NewDefaultAlignOptions()
	reportOpts.Alignments = []brimtext.Alignment{brimtext.Right, brimtext.Left}
	fmted := false
OUT:
	for _, values := range tiers {
		for _, value := range values {
			if strings.Contains(value, " ") {
				fmted = true
				break OUT
			}
		}
	}
	for level, values := range tiers {
		sort.Strings(values)
		var pvalue string
		if fmted {
			for _, value := range values {
				pvalue += fmt.Sprintf(" %#v", value)
			}
			pvalue = strings.Trim(pvalue, " ")
		} else {
			pvalue = strings.Join(values, " ")
		}
		report = append(report, []string{
			strconv.Itoa(level),
			strings.Trim(pvalue, " "),
		})
	}
	fmt.Print(brimtext.Align(report, reportOpts))
	return nil
}

func mainCmd(r ring.Ring, b *ring.Builder) error {
	if r != nil {
		// TODO:
		//  Version Info (the value as well as the time translation)
		//  Number of tier levels
		//  Replica count
		//  Indication of how risky the assignments are:
		//      Replicas not in distinct tiers, nodes
		s := r.Stats()
		report := [][]string{
			[]string{brimtext.ThousandsSep(int64(s.PartitionCount), ","), "Partitions"},
			[]string{brimtext.ThousandsSep(int64(s.PartitionBitCount), ","), "Partition Bits"},
			[]string{brimtext.ThousandsSep(int64(s.NodeCount), ","), "Nodes"},
			[]string{brimtext.ThousandsSep(int64(s.InactiveNodeCount), ","), "Inactive Nodes"},
			[]string{brimtext.ThousandsSepU(s.TotalCapacity, ","), "Total Node Capacity"},
			[]string{fmt.Sprintf("%.02f%%", s.MaxUnderNodePercentage), fmt.Sprintf("Worst Underweight Node (ID %016x)", s.MaxUnderNodeID)},
			[]string{fmt.Sprintf("%.02f%%", s.MaxOverNodePercentage), fmt.Sprintf("Worst Overweight Node (ID %016x)", s.MaxOverNodeID)},
		}
		reportOpts := brimtext.NewDefaultAlignOptions()
		reportOpts.Alignments = []brimtext.Alignment{brimtext.Right, brimtext.Left}
		fmt.Print(brimtext.Align(report, reportOpts))
	}
	if b != nil {
		// TODO:
		//  Inactive node count
		//  Total capacity
		report := [][]string{
			[]string{brimtext.ThousandsSep(int64(len(b.Nodes())), ","), "Nodes"},
			[]string{brimtext.ThousandsSep(int64(b.ReplicaCount()), ","), "Replicas"},
			[]string{brimtext.ThousandsSep(int64(b.PointsAllowed()), ","), "Points Allowed"},
			[]string{brimtext.ThousandsSep(int64(b.MaxPartitionBitCount()), ","), "Max Partition Bits"},
			[]string{brimtext.ThousandsSep(int64(b.MoveWait()), ","), "Move Wait"},
		}
		reportOpts := brimtext.NewDefaultAlignOptions()
		reportOpts.Alignments = []brimtext.Alignment{brimtext.Right, brimtext.Left}
		fmt.Print(brimtext.Align(report, reportOpts))
		return nil
	}
	return nil
}

//TODO: Need concurrency, we should just fire of replicates in goroutines
// and collects the results. On a failure we still need to send the rollback
// or have the slave's commit deadline trigger.
func (s *Server) replicateRing(r ring.Ring, rb, bb *[]byte) error {
	failcount := 0
	for _, slave := range s.slaves {
		ctx, _ := context.WithTimeout(context.Background(), time.Duration(_SYN_REGISTER_TIMEOUT)*time.Second)
		i := &pb.RingMsg{
			Version:  r.Version(),
			Ring:     *rb,
			Builder:  *bb,
			Deadline: time.Now().Add(60 * time.Second).Unix(),
			Rollback: s.r.Version(),
		}
		res, err := slave.client.Store(ctx, i)
		if err != nil {
			log.Println(err)
			failcount++
			continue
		}
		if res.Version != r.Version() {
			log.Printf("Version or master on remote node %+v did not match local entries. Got %+v.", slave, res)
			failcount++
			continue
		}
		if !res.Ring || !res.Builder {
			log.Printf("res is: %#v\n", res)
			log.Printf("Slave failed to store ring or builder: %s", res.ErrMsg)
			failcount++
			continue
		}
		log.Printf("<-- Slave response: %+v", res)
		slave.version = res.Version
		slave.last = time.Now()
		slave.status = true
	}
	if failcount > (len(s.slaves) / 2) {
		return fmt.Errorf("Failed to get replication majority")
	}
	return nil
}

func persist(r ring.Ring, b *ring.Builder, filename string) error {
	dir, name := path.Split(filename)
	if dir == "" {
		dir = "."
	}
	f, err := ioutil.TempFile(dir, name+".")
	if err != nil {
		return err
	}
	tmp := f.Name()
	if r != nil {
		err = r.Persist(f)
	} else {
		err = b.Persist(f)
	}
	if err != nil {
		f.Close()
		return err
	}
	if err = f.Close(); err != nil {
		return err
	}
	return os.Rename(path.Join(dir, tmp), filename)
}

func nodeCmd(r ring.Ring, b *ring.Builder, args []string, full bool) (changed bool, err error) {
	var nodes ring.NodeSlice
	if r != nil {
		nodes = r.Nodes()
	} else {
		bnodes := b.Nodes()
		nodes = make(ring.NodeSlice, len(bnodes))
		for i := len(nodes) - 1; i >= 0; i-- {
			nodes[i] = bnodes[i]
		}
	}
	filterArgs := make([]string, 0)
	setArgs := make([]string, 0)
	setFound := false
	for _, arg := range args {
		if arg == "set" {
			setFound = true
			continue
		}
		if setFound {
			setArgs = append(setArgs, arg)
		} else {
			filterArgs = append(filterArgs, arg)
		}
	}
	if len(setArgs) > 0 && b == nil {
		err = fmt.Errorf("set is only valid for builder files")
		return
	}
	if nodes, err = nodes.Filter(filterArgs); err != nil {
		return
	}
	if len(nodes) > 0 && len(setArgs) > 0 {
		for _, n := range nodes {
			if err = addOrSetCmd(r, b, setArgs, n.(ring.BuilderNode)); err != nil {
				return
			}
			changed = true
		}
	}
	if full || len(nodes) == 1 {
		first := true
		for _, n := range nodes {
			if first {
				first = false
			} else {
				fmt.Println()
			}
			report := [][]string{
				[]string{"ID:", fmt.Sprintf("%016x", n.ID())},
				[]string{"Active:", fmt.Sprintf("%v", n.Active())},
				[]string{"Capacity:", fmt.Sprintf("%d", n.Capacity())},
				[]string{"Tiers:", strings.Join(n.Tiers(), "\n")},
				[]string{"Addresses:", strings.Join(n.Addresses(), "\n")},
				[]string{"Meta:", n.Meta()},
			}
			fmt.Print(brimtext.Align(report, nil))
		}
		return
	}
	header := []string{
		"ID",
		"Active",
		"Capacity",
		"Address",
		"Meta",
	}
	report := [][]string{header}
	reportAlign := brimtext.NewDefaultAlignOptions()
	reportAlign.Alignments = []brimtext.Alignment{
		brimtext.Left,
		brimtext.Right,
		brimtext.Right,
		brimtext.Right,
		brimtext.Left,
	}
	reportLine := func(n ring.Node) []string {
		return []string{
			fmt.Sprintf("%016x", n.ID()),
			fmt.Sprintf("%v", n.Active()),
			fmt.Sprintf("%d", n.Capacity()),
			n.Address(0),
			n.Meta(),
		}
	}
	for _, n := range nodes {
		if n.Active() {
			report = append(report, reportLine(n))
		}
	}
	for _, n := range nodes {
		if !n.Active() {
			report = append(report, reportLine(n))
		}
	}
	fmt.Print(brimtext.Align(report, reportAlign))
	return
}