package cluster import ( "github.com/chrislusf/seaweedfs/weed/pb" "github.com/chrislusf/seaweedfs/weed/pb/master_pb" "math" "sync" "time" ) const ( MasterType = "master" FilerType = "filer" BrokerType = "broker" ) type ClusterNode struct { Address pb.ServerAddress Version string counter int createdTs time.Time } type Leaders struct { leaders [3]pb.ServerAddress } type Cluster struct { filers map[pb.ServerAddress]*ClusterNode filersLock sync.RWMutex filerLeaders *Leaders } func NewCluster() *Cluster { return &Cluster{ filers: make(map[pb.ServerAddress]*ClusterNode), filerLeaders: &Leaders{}, } } func (cluster *Cluster) AddClusterNode(nodeType string, address pb.ServerAddress, version string) []*master_pb.KeepConnectedResponse { switch nodeType { case FilerType: cluster.filersLock.Lock() defer cluster.filersLock.Unlock() if existingNode, found := cluster.filers[address]; found { existingNode.counter++ return nil } cluster.filers[address] = &ClusterNode{ Address: address, Version: version, counter: 1, createdTs: time.Now(), } return cluster.ensureFilerLeaders(true, nodeType, address) case MasterType: } return nil } func (cluster *Cluster) RemoveClusterNode(nodeType string, address pb.ServerAddress) []*master_pb.KeepConnectedResponse { switch nodeType { case FilerType: cluster.filersLock.Lock() defer cluster.filersLock.Unlock() if existingNode, found := cluster.filers[address]; !found { return nil } else { existingNode.counter-- if existingNode.counter <= 0 { delete(cluster.filers, address) return cluster.ensureFilerLeaders(false, nodeType, address) } } case MasterType: } return nil } func (cluster *Cluster) ListClusterNode(nodeType string) (nodes []*ClusterNode) { switch nodeType { case FilerType: cluster.filersLock.RLock() defer cluster.filersLock.RUnlock() for _, node := range cluster.filers { nodes = append(nodes, node) } case MasterType: } return } func (cluster *Cluster) IsOneLeader(address pb.ServerAddress) bool { return cluster.filerLeaders.isOneLeader(address) } func (cluster *Cluster) ensureFilerLeaders(isAdd bool, nodeType string, address pb.ServerAddress) (result []*master_pb.KeepConnectedResponse) { if isAdd { if cluster.filerLeaders.addLeaderIfVacant(address) { // has added the address as one leader result = append(result, &master_pb.KeepConnectedResponse{ ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{ NodeType: nodeType, Address: string(address), IsLeader: true, IsAdd: true, }, }) } else { result = append(result, &master_pb.KeepConnectedResponse{ ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{ NodeType: nodeType, Address: string(address), IsLeader: false, IsAdd: true, }, }) } } else { if cluster.filerLeaders.removeLeaderIfExists(address) { result = append(result, &master_pb.KeepConnectedResponse{ ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{ NodeType: nodeType, Address: string(address), IsLeader: true, IsAdd: false, }, }) // pick the freshest one, since it is less likely to go away var shortestDuration int64 = math.MaxInt64 now := time.Now() var candidateAddress pb.ServerAddress for _, node := range cluster.filers { if cluster.filerLeaders.isOneLeader(node.Address) { continue } duration := now.Sub(node.createdTs).Nanoseconds() if duration < shortestDuration { shortestDuration = duration candidateAddress = node.Address } } if candidateAddress != "" { cluster.filerLeaders.addLeaderIfVacant(candidateAddress) // added a new leader result = append(result, &master_pb.KeepConnectedResponse{ ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{ NodeType: nodeType, Address: string(candidateAddress), IsLeader: true, IsAdd: true, }, }) } } else { result = append(result, &master_pb.KeepConnectedResponse{ ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{ NodeType: nodeType, Address: string(address), IsLeader: false, IsAdd: false, }, }) } } return } func (leaders *Leaders) addLeaderIfVacant(address pb.ServerAddress) (hasChanged bool) { if leaders.isOneLeader(address) { return } for i := 0; i < len(leaders.leaders); i++ { if leaders.leaders[i] == "" { leaders.leaders[i] = address hasChanged = true return } } return } func (leaders *Leaders) removeLeaderIfExists(address pb.ServerAddress) (hasChanged bool) { if !leaders.isOneLeader(address) { return } for i := 0; i < len(leaders.leaders); i++ { if leaders.leaders[i] == address { leaders.leaders[i] = "" hasChanged = true return } } return } func (leaders *Leaders) isOneLeader(address pb.ServerAddress) bool { for i := 0; i < len(leaders.leaders); i++ { if leaders.leaders[i] == address { return true } } return false } func (leaders *Leaders) GetLeaders() (addresses []pb.ServerAddress) { for i := 0; i < len(leaders.leaders); i++ { if leaders.leaders[i] != "" { addresses = append(addresses, leaders.leaders[i]) } } return }