builder

pkg/discoveryregistry/zookeeper/zk.go

@@ -0,0 +1,187 @@
+package openKeeper
+
+import (
+	"net"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/go-zookeeper/zk"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/resolver"
+)
+
+const (
+	defaultFreq = time.Minute * 30
+	timeout     = 5
+)
+
+type ZkClient struct {
+	zkServers []string
+	zkRoot    string
+	userName  string
+	password  string
+
+	scheme string
+
+	timeout   int
+	conn      *zk.Conn
+	eventChan <-chan zk.Event
+	node      string
+	ticker    *time.Ticker
+
+	lock    sync.RWMutex
+	options []grpc.DialOption
+
+	resolvers    map[string]*Resolver
+	localConns   map[string][]resolver.Address
+	balancerName string
+}
+
+type ZkOption func(*ZkClient)
+
+func WithRoundRobin() ZkOption {
+	return func(client *ZkClient) {
+		client.balancerName = "round_robin"
+	}
+}
+
+func WithUserNameAndPassword(userName, password string) ZkOption {
+	return func(client *ZkClient) {
+		client.userName = userName
+		client.password = password
+	}
+}
+
+func WithOptions(opts ...grpc.DialOption) ZkOption {
+	return func(client *ZkClient) {
+		client.options = opts
+	}
+}
+
+func WithFreq(freq time.Duration) ZkOption {
+	return func(client *ZkClient) {
+		client.ticker = time.NewTicker(freq)
+	}
+}
+
+func WithTimeout(timeout int) ZkOption {
+	return func(client *ZkClient) {
+		client.timeout = timeout
+	}
+}
+
+func NewClient(zkServers []string, zkRoot string, options ...ZkOption) (*ZkClient, error) {
+	client := &ZkClient{
+		zkServers:  zkServers,
+		zkRoot:     "/",
+		scheme:     zkRoot,
+		timeout:    timeout,
+		localConns: make(map[string][]resolver.Address),
+		resolvers:  make(map[string]*Resolver),
+	}
+	client.ticker = time.NewTicker(defaultFreq)
+	for _, option := range options {
+		option(client)
+	}
+	conn, eventChan, err := zk.Connect(zkServers, time.Duration(client.timeout)*time.Second, zk.WithLogInfo(false))
+	if err != nil {
+		return nil, err
+	}
+	if client.userName != "" && client.password != "" {
+		if err := conn.AddAuth("digest", []byte(client.userName+":"+client.password)); err != nil {
+			return nil, err
+		}
+	}
+	client.zkRoot += zkRoot
+	client.eventChan = eventChan
+	client.conn = conn
+	if err := client.ensureRoot(); err != nil {
+		client.CloseZK()
+		return nil, err
+	}
+	resolver.Register(client)
+	var wg sync.WaitGroup
+	wg.Add(2)
+	go client.refresh(&wg)
+	go client.watch(&wg)
+	wg.Wait()
+	return client, nil
+}
+
+func (s *ZkClient) CloseZK() {
+	s.conn.Close()
+}
+
+func (s *ZkClient) ensureAndCreate(node string) error {
+	exists, _, err := s.conn.Exists(node)
+	if err != nil {
+		return err
+	}
+	if !exists {
+		_, err := s.conn.Create(node, []byte(""), 0, zk.WorldACL(zk.PermAll))
+		if err != nil && err != zk.ErrNodeExists {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *ZkClient) refresh(wg *sync.WaitGroup) {
+	wg.Done()
+	for range s.ticker.C {
+		s.lock.Lock()
+		for rpcName := range s.resolvers {
+			s.flushResolver(rpcName)
+		}
+		for rpcName := range s.localConns {
+			delete(s.localConns, rpcName)
+		}
+		s.lock.Unlock()
+	}
+
+}
+
+func (s *ZkClient) flushResolver(serviceName string) {
+	r, ok := s.resolvers[serviceName]
+	if ok {
+		r.ResolveNow(resolver.ResolveNowOptions{})
+		s.resolvers[serviceName] = r
+	}
+}
+
+func (s *ZkClient) GetZkConn() *zk.Conn {
+	return s.conn
+}
+
+func (s *ZkClient) GetRootPath() string {
+	return s.zkRoot
+}
+
+func (s *ZkClient) GetNode() string {
+	return s.node
+}
+
+func (s *ZkClient) ensureRoot() error {
+	return s.ensureAndCreate(s.zkRoot)
+}
+
+func (s *ZkClient) ensureName(rpcRegisterName string) error {
+	return s.ensureAndCreate(s.getPath(rpcRegisterName))
+}
+
+func (s *ZkClient) getPath(rpcRegisterName string) string {
+	return s.zkRoot + "/" + rpcRegisterName
+}
+
+func (s *ZkClient) getAddr(host string, port int) string {
+	return net.JoinHostPort(host, strconv.Itoa(port))
+}
+
+func (s *ZkClient) AddOption(opts ...grpc.DialOption) {
+	s.options = append(s.options, opts...)
+}
+
+func (s *ZkClient) GetClientLocalConns() map[string][]resolver.Address {
+	return s.localConns
+}