Golang log.Println函數代碼示例

//
// 獲取下一個可用的Worker
//
func (pq *PriorityQueue) NextWorker() *Worker {
	now := time.Now()
	for pq.Len() > 0 {
		result := (*pq)[0]

		if result.index != INVALID_INDEX && result.Expire.After(now) {
			// 隻要活著，就留在優先級隊列中，等待分配任務
			//			log.Println("Find Valid Worker...")

			result.priority -= 1

			// 調整Worker的優先級
			heap.Fix(pq, result.index)

			return result
		} else {
			if result.index != INVALID_INDEX {
				log.Errorf("Invalid Item index in PriorityQueue#NextWorker")
			} else {
				log.Println("Worker Expired")
				// 隻有過期的元素才刪除
				heap.Remove(pq, result.index)
			}
		}
	}

	log.Println("Has Not Worker...")
	return nil

}

// 創建一個BackService
func NewBackService(serviceName string, poller *zmq.Poller, topo *zk.Topology) *BackService {

	backSockets := NewBackSockets(poller)

	service := &BackService{
		ServiceName: serviceName,
		backend:     backSockets,
		poller:      poller,
		topo:        topo,
	}

	var evtbus chan interface{} = make(chan interface{}, 2)
	servicePath := topo.ProductServicePath(serviceName)
	endpoints, err := topo.WatchChildren(servicePath, evtbus)
	if err != nil {
		log.Println("Error: ", err)
		panic("Reading Service List Failed: ")
	}

	go func() {
		for true {
			// 如何監聽endpoints的變化呢?
			addrSet := make(map[string]bool)
			nowStr := time.Now().Format("@2006-01-02 15:04:05")
			for _, endpoint := range endpoints {
				// 這些endpoint變化該如何處理呢?
				log.Println(utils.Green("---->Find Endpoint: "), endpoint, "For Service: ", serviceName)
				endpointInfo, _ := topo.GetServiceEndPoint(serviceName, endpoint)

				addr, ok := endpointInfo["frontend"]
				if ok {
					addrStr := addr.(string)
					log.Println(utils.Green("---->Add endpoint to backend: "), addrStr, nowStr, "For Service: ", serviceName)
					addrSet[addrStr] = true
				}
			}

			service.backend.UpdateEndpointAddrs(addrSet)

			// 等待事件
			<-evtbus
			// 讀取數據，繼續監聽
			endpoints, err = topo.WatchChildren(servicePath, evtbus)
		}
	}()

	ticker := time.NewTicker(time.Millisecond * 1000)
	go func() {
		for _ = range ticker.C {
			service.backend.PurgeEndpoints()
		}
	}()

	return service

}

//
// 刪除Service Endpoint
//
func (s *ServiceEndpoint) DeleteServiceEndpoint(top *zk.Topology) {
	path := top.ProductServiceEndPointPath(s.Service, s.ServiceId)
	if ok, _ := top.Exist(path); ok {
		zkhelper.DeleteRecursive(top.ZkConn, path, -1)
		log.Println(Red("DeleteServiceEndpoint"), "Path: ", path)
	}
}

func NewBackServices(poller *zmq.Poller, productName string, topo *zk.Topology) *BackServices {

	// 創建BackServices
	result := &BackServices{
		Services:        make(map[string]*BackService),
		OfflineServices: make(map[string]*BackService),
		poller:          poller,
		topo:            topo,
	}

	var evtbus chan interface{} = make(chan interface{}, 2)
	servicesPath := topo.ProductServicesPath()
	path, e1 := topo.CreateDir(servicesPath) // 保證Service目錄存在，否則會報錯
	fmt.Println("Path: ", path, "error: ", e1)
	services, err := topo.WatchChildren(servicesPath, evtbus)
	if err != nil {
		log.Println("Error: ", err)
		// TODO: 這個地方需要優化
		panic("Reading Service List Failed")
	}

	go func() {
		for true {

			result.Lock()
			for _, service := range services {
				log.Println("Service: ", service)
				if _, ok := result.Services[service]; !ok {
					result.addBackService(service)
				}
			}
			result.Unlock()

			// 等待事件
			<-evtbus
			// 讀取數據，繼續監聽(連接過期了就過期了，再次Watch即可)
			services, err = topo.WatchChildren(servicesPath, evtbus)
		}
	}()

	// 讀取zk, 等待
	log.Println("ProductName: ", result.topo.ProductName)

	return result
}

// 創建指定的Path
func (top *Topology) CreateDir(path string) (string, error) {
	dir := top.FullPath(path)
	if ok, _ := top.Exist(dir); ok {
		log.Println("Path Exists")
		return dir, nil
	} else {
		return zkhelper.CreateRecursive(top.ZkConn, dir, "", 0, zkhelper.DefaultDirACLs())
	}
}

//
// 將消息發送到Backend上去
//
func (s *BackService) HandleRequest(client_id string, msgs []string) (total int, err error, msg *[]byte) {

	backSocket := s.backend.NextSocket()
	if backSocket == nil {
		// 沒有後端服務

		if config.VERBOSE {
			log.Println(utils.Red("No BackSocket Found for service:"), s.ServiceName)
		}
		errMsg := GetWorkerNotFoundData(s.ServiceName, 0)
		return 0, nil, &errMsg
	} else {
		if config.VERBOSE {
			log.Println("SendMessage With: ", backSocket.Addr, "For Service: ", s.ServiceName)
		}
		total, err = backSocket.SendMessage("", client_id, "", msgs)
		return total, err, nil
	}
}

// 在第一次使用時再連接
func (p *BackSocket) connect() error {
	var err error
	p.Socket, err = zmq.NewSocket(zmq.DEALER)
	if err == nil {
		// 這個Id存在問題:
		socketSeq += 1
		p.Socket.SetIdentity(fmt.Sprintf("proxy-%d-%d", os.Getpid(), socketSeq))

		p.Socket.Connect(p.Addr)
		// 都隻看數據的輸入
		// 數據的輸出經過異步處理，不用考慮時間的問題
		p.poller.Add(p.Socket, zmq.POLLIN)
		log.Println("Socket Create Succeed")
		return nil
	} else {
		log.Println("Socket Create Failed: ", err)
		return err
	}
}

func (p *BackSocket) SendMessage(parts ...interface{}) (total int, err error) {
	if p.Socket == nil {
		err := p.connect()
		if err != nil {
			log.Println("Socket Connect Failed")
			return 0, err
		}
	}

	return p.Socket.SendMessage(parts...)
}

//
// 設置RPC Proxy的數據:
//     綁定的前端的ip/port, 例如: {"rpc_front": "tcp://127.0.0.1:5550"}
//
func (top *Topology) SetRpcProxyData(proxyInfo map[string]interface{}) error {
	path := top.FullPath("/rpc_proxy")
	data, err := json.Marshal(proxyInfo)
	if err != nil {
		return err
	}

	// topo.FlagEphemeral 這裏的ProxyInfo是手動配置的，需要持久化
	path, err = CreateOrUpdate(top.ZkConn, path, string(data), 0, zkhelper.DefaultDirACLs(), true)
	log.Println(green("SetRpcProxyData"), "Path: ", path, ", Error: ", err, ", Data: ", string(data))
	return err
}

func (pq *PPQueue) PurgeExpired() {
	now := time.Now()
	expiredWokers := make([]*Worker, 0)
	// 給workerQueue中的所有的worker發送心跳消息
	for _, worker := range pq.WorkerQueue {
		if worker.Expire.Before(now) {
			fmt.Println("Purge Worker: ", worker.Identity, ", At Index: ", worker.index)
			expiredWokers = append(expiredWokers, worker)
		}
	}

	log.Println("expiredWokers: ", len(expiredWokers))

	// 刪除過期的Worker
	for _, worker := range expiredWokers {
		log.Println("Purge Worker: ", worker.Identity, ", At Index: ", worker.index)
		heap.Remove(&(pq.WorkerQueue), worker.index)
		delete(pq.id2item, worker.Identity)
	}

	log.Println("Available Workers: ", green(fmt.Sprintf("%d", len(pq.WorkerQueue))))
}

//
// 將消息發送到Backend上去
//
func (s *BackService) HandleRequest(req *Request) (err error) {
	backendConn := s.NextBackendConn()

	s.lastRequestTime.Set(time.Now().Unix())

	if backendConn == nil {
		// 沒有後端服務
		if s.verbose {
			log.Println(Red("No BackSocket Found for service:"), s.serviceName)
		}
		// 從errMsg來構建異常
		errMsg := GetWorkerNotFoundData(req, "BackService")
		req.Response.Data = errMsg

		return nil
	} else {
		if s.verbose {
			log.Println("SendMessage With: ", backendConn.Addr(), "For Service: ", s.serviceName)
		}
		backendConn.PushBack(req)
		return nil
	}
}

func (conf *Config) getFrontendAddr() string {
	var frontendAddr = ""
	// 如果沒有指定FrontHost, 則自動根據 IpPrefix來進行篩選，
	// 例如: IpPrefix: 10., 那麽最終內網IP： 10.4.10.2之類的被選中
	if conf.FrontHost == "" {
		log.Println("FrontHost: ", conf.FrontHost, ", Prefix: ", conf.IpPrefix)
		if conf.IpPrefix != "" {
			conf.FrontHost = GetIpWithPrefix(conf.IpPrefix)
		}
	}
	if conf.FrontPort != "" && conf.FrontHost != "" {
		frontendAddr = fmt.Sprintf("tcp://%s:%s", conf.FrontHost, conf.FrontPort)
	}
	return frontendAddr
}

//
// 讀取RPC Proxy的數據:
//     綁定的前端的ip/port, 例如: {"rpc_front": "tcp://127.0.0.1:5550"}
//
func (top *Topology) GetRpcProxyData() (proxyInfo map[string]interface{}, e error) {
	path := top.FullPath("/rpc_proxy")
	data, _, err := top.ZkConn.Get(path)

	log.Println("Data: ", data, ", err: ", err)
	if err != nil {
		return nil, err
	}
	proxyInfo = make(map[string]interface{})
	err = json.Unmarshal(data, &proxyInfo)
	if err != nil {
		return nil, err
	} else {
		return proxyInfo, nil
	}
}

//
// 將不在: addrSet中的endPoint標記為下線
//
func (p *BackSockets) UpdateEndpointAddrs(addrSet map[string]bool) {
	p.Lock()
	defer p.Unlock()

	var addr string
	for addr, _ = range addrSet {
		p.addEndpoint(addr)
	}

	now := time.Now().Format("@2006-01-02 15:04:05")
	for i := 0; i < p.Active; i++ {
		if _, ok := addrSet[p.Sockets[i].Addr]; !ok {
			log.Println(utils.Red("MarkEndpointsOffline#Mark Backend Offline: "), p.Sockets[i].Addr, now)

			p.markOffline(p.Sockets[i])
			i--
		}
	}
}

//
// 通過參數依賴，保證getFrontendAddr的調用位置（必須等待Host, IpPrefix, Port讀取完畢之後)
//
func (conf *Config) getFrontendAddr(frontHost, ipPrefix, frontPort string) string {
	if conf.FrontSock != "" {
		return conf.FrontSock
	}

	var frontendAddr = ""
	// 如果沒有指定FrontHost, 則自動根據 IpPrefix來進行篩選，
	// 例如: IpPrefix: 10., 那麽最終內網IP： 10.4.10.2之類的被選中
	if frontHost == "" {
		log.Println("FrontHost: ", frontHost, ", Prefix: ", ipPrefix)
		if ipPrefix != "" {
			frontHost = GetIpWithPrefix(ipPrefix)
		}
	}
	if frontPort != "" && frontHost != "" {
		frontendAddr = fmt.Sprintf("%s:%s", frontHost, frontPort)
	}
	return frontendAddr
}