| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package zookeeper |
| |
| import ( |
| "strings" |
| "sync" |
| "time" |
| ) |
| |
| import ( |
| "github.com/dubbogo/go-zookeeper/zk" |
| gzk "github.com/dubbogo/gost/database/kv/zk" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go-pixiu/pkg/adapter/springcloud/common" |
| "github.com/apache/dubbo-go-pixiu/pkg/logger" |
| ) |
| |
| type applicationServiceListener struct { |
| servicePath string |
| serviceName string |
| exit chan struct{} |
| wg sync.WaitGroup |
| |
| ds *zookeeperDiscovery |
| } |
| |
| func newApplicationServiceListener(path string, serviceName string, ds *zookeeperDiscovery) *applicationServiceListener { |
| return &applicationServiceListener{ |
| servicePath: path, |
| exit: make(chan struct{}), |
| ds: ds, |
| serviceName: serviceName, |
| } |
| } |
| |
| func (asl *applicationServiceListener) WatchAndHandle() { |
| defer asl.wg.Done() |
| |
| var ( |
| failTimes int64 = 0 |
| delayTimer = time.NewTimer(ConnDelay * time.Duration(failTimes)) |
| ) |
| defer delayTimer.Stop() |
| for { |
| children, e, err := asl.ds.getClient().GetChildrenW(asl.servicePath) |
| if err != nil { |
| failTimes++ |
| logger.Infof("watching (path{%s}) = error{%v}", asl.servicePath, err) |
| if err == zk.ErrNoChildrenForEphemerals { |
| return |
| } |
| if err == zk.ErrNoNode { |
| logger.Errorf("watching (path{%s}) got errNilNode,so exit listen", asl.servicePath) |
| return |
| } |
| if failTimes > MaxFailTimes { |
| logger.Errorf("Error happens on (path{%s}) exceed max fail times: %v,so exit listen", asl.servicePath, MaxFailTimes) |
| return |
| } |
| delayTimer.Reset(ConnDelay * time.Duration(failTimes)) |
| <-delayTimer.C |
| continue |
| } |
| failTimes = 0 |
| if continueLoop := asl.watchEventHandle(children, e); !continueLoop { |
| return |
| } |
| } |
| } |
| |
| func (asl *applicationServiceListener) watchEventHandle(children []string, e <-chan zk.Event) bool { |
| tickerTTL := defaultTTL |
| ticker := time.NewTicker(tickerTTL) |
| defer ticker.Stop() |
| asl.handleEvent(children) |
| for { |
| select { |
| case <-ticker.C: |
| asl.handleEvent(children) |
| case zkEvent := <-e: |
| logger.Debugf("get a zookeeper e{type:%s, server:%s, path:%s, state:%d-%s, err:%s}", |
| zkEvent.Type.String(), zkEvent.Server, zkEvent.Path, zkEvent.State, gzk.StateToString(zkEvent.State), zkEvent.Err) |
| asl.handleEvent(children) |
| return true |
| case <-asl.exit: |
| logger.Warnf("listen(path{%s}) goroutine exit now...", asl.servicePath) |
| return false |
| } |
| } |
| } |
| |
| func (asl *applicationServiceListener) handleEvent(children []string) { |
| |
| fetchChildren, err := asl.ds.getClient().GetChildren(asl.servicePath) |
| if err != nil { |
| // todo refactor gost zk, make it return the definite err |
| if strings.Contains(err.Error(), "none children") { |
| logger.Debugf("%s get nodes from zookeeper fail: %s", common.ZKLogDiscovery, err.Error()) |
| } else { |
| logger.Warnf("%s Error when retrieving service node [%s] in path: %s, Error:%s", common.ZKLogDiscovery, asl.serviceName, asl.servicePath, err.Error()) |
| } |
| } |
| discovery := asl.ds |
| serviceMap := discovery.getServiceMap() |
| instanceMap := discovery.instanceMap |
| |
| func() { |
| for _, id := range fetchChildren { |
| serviceInstance, err := discovery.queryForInstance(asl.serviceName, id) |
| if err != nil { |
| logger.Errorf("add service: %s, instance: %s has error: ", asl.serviceName, id, err.Error()) |
| continue |
| } |
| if instanceMap[id] == nil { |
| _, _ = discovery.addServiceInstance(serviceInstance) |
| } else { |
| _, _ = discovery.updateServiceInstance(serviceInstance) |
| } |
| } |
| }() |
| |
| func() { |
| serviceInstances := serviceMap[asl.serviceName] |
| oldInsId := []string{} |
| for _, instance := range serviceInstances { |
| oldInsId = append(oldInsId, instance.ID) |
| } |
| if delInstanceIds := Diff(oldInsId, fetchChildren); delInstanceIds != nil { |
| for _, id := range delInstanceIds { |
| _, _ = discovery.delServiceInstance(instanceMap[id]) |
| } |
| } |
| }() |
| } |
| |
| // Close closes this listener |
| func (asl *applicationServiceListener) Close() { |
| close(asl.exit) |
| asl.wg.Wait() |
| } |