// Package etcd is an etcd implementation of lock package etcd import ( "context" "errors" "log" "path" "strings" "sync" "github.com/micro/go-micro/sync/lock" client "go.etcd.io/etcd/clientv3" cc "go.etcd.io/etcd/clientv3/concurrency" ) type etcdLock struct { opts lock.Options path string client *client.Client sync.Mutex locks map[string]*elock } type elock struct { s *cc.Session m *cc.Mutex } func (e *etcdLock) Acquire(id string, opts ...lock.AcquireOption) error { var options lock.AcquireOptions for _, o := range opts { o(&options) } // make path path := path.Join(e.path, strings.Replace(e.opts.Prefix+id, "/", "-", -1)) var sopts []cc.SessionOption if options.TTL > 0 { sopts = append(sopts, cc.WithTTL(int(options.TTL.Seconds()))) } s, err := cc.NewSession(e.client, sopts...) if err != nil { return err } m := cc.NewMutex(s, path) ctx, _ := context.WithCancel(context.Background()) if err := m.Lock(ctx); err != nil { return err } e.Lock() e.locks[id] = &elock{ s: s, m: m, } e.Unlock() return nil } func (e *etcdLock) Release(id string) error { e.Lock() defer e.Unlock() v, ok := e.locks[id] if !ok { return errors.New("lock not found") } err := v.m.Unlock(context.Background()) delete(e.locks, id) return err } func (e *etcdLock) String() string { return "etcd" } func NewLock(opts ...lock.Option) lock.Lock { var options lock.Options for _, o := range opts { o(&options) } var endpoints []string for _, addr := range options.Nodes { if len(addr) > 0 { endpoints = append(endpoints, addr) } } if len(endpoints) == 0 { endpoints = []string{"http://127.0.0.1:2379"} } // TODO: parse addresses c, err := client.New(client.Config{ Endpoints: endpoints, }) if err != nil { log.Fatal(err) } return &etcdLock{ path: "/micro/lock", client: c, opts: options, locks: make(map[string]*elock), } }