package register import ( "context" "errors" "sync" "time" "github.com/unistack-org/micro/v3/logger" "github.com/unistack-org/micro/v3/util/id" ) var ( sendEventTime = 10 * time.Millisecond ttlPruneTime = time.Second ) type node struct { LastSeen time.Time *Node TTL time.Duration } type record struct { Name string Version string Metadata map[string]string Nodes map[string]*node Endpoints []*Endpoint } type memory struct { records map[string]services watchers map[string]*watcher opts Options sync.RWMutex } // services is a KV map with service name as the key and a map of records as the value type services map[string]map[string]*record // NewRegister returns an initialized in-memory register func NewRegister(opts ...Option) Register { r := &memory{ opts: NewOptions(opts...), records: make(map[string]services), watchers: make(map[string]*watcher), } go r.ttlPrune() return r } func (m *memory) ttlPrune() { prune := time.NewTicker(ttlPruneTime) defer prune.Stop() for range prune.C { m.Lock() for domain, services := range m.records { for service, versions := range services { for version, record := range versions { for id, n := range record.Nodes { if n.TTL != 0 && time.Since(n.LastSeen) > n.TTL { if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register TTL expired for node %s of service %s", n.ID, service) } delete(m.records[domain][service][version].Nodes, id) } } } } } m.Unlock() } } func (m *memory) sendEvent(r *Result) { m.RLock() watchers := make([]*watcher, 0, len(m.watchers)) for _, w := range m.watchers { watchers = append(watchers, w) } m.RUnlock() for _, w := range watchers { select { case <-w.exit: m.Lock() delete(m.watchers, w.id) m.Unlock() default: select { case w.res <- r: case <-time.After(sendEventTime): } } } } func (m *memory) Connect(ctx context.Context) error { return nil } func (m *memory) Disconnect(ctx context.Context) error { return nil } func (m *memory) Init(opts ...Option) error { for _, o := range opts { o(&m.opts) } // add services m.Lock() defer m.Unlock() return nil } func (m *memory) Options() Options { return m.opts } func (m *memory) Register(ctx context.Context, s *Service, opts ...RegisterOption) error { m.Lock() defer m.Unlock() options := NewRegisterOptions(opts...) // get the services for this domain from the register srvs, ok := m.records[options.Domain] if !ok { srvs = make(services) } // domain is set in metadata so it can be passed to watchers if s.Metadata == nil { s.Metadata = map[string]string{"domain": options.Domain} } else { s.Metadata["domain"] = options.Domain } // ensure the service name exists r := serviceToRecord(s, options.TTL) if _, ok := srvs[s.Name]; !ok { srvs[s.Name] = make(map[string]*record) } if _, ok := srvs[s.Name][s.Version]; !ok { srvs[s.Name][s.Version] = r if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register added new service: %s, version: %s", s.Name, s.Version) } m.records[options.Domain] = srvs go m.sendEvent(&Result{Action: "create", Service: s}) } var addedNodes bool for _, n := range s.Nodes { // check if already exists if _, ok := srvs[s.Name][s.Version].Nodes[n.ID]; ok { continue } metadata := make(map[string]string) // make copy of metadata for k, v := range n.Metadata { metadata[k] = v } // set the domain metadata["domain"] = options.Domain // add the node srvs[s.Name][s.Version].Nodes[n.ID] = &node{ Node: &Node{ ID: n.ID, Address: n.Address, Metadata: metadata, }, TTL: options.TTL, LastSeen: time.Now(), } addedNodes = true } if addedNodes { if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register added new node to service: %s, version: %s", s.Name, s.Version) } go m.sendEvent(&Result{Action: "update", Service: s}) } else { // refresh TTL and timestamp for _, n := range s.Nodes { if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Updated registration for service: %s, version: %s", s.Name, s.Version) } srvs[s.Name][s.Version].Nodes[n.ID].TTL = options.TTL srvs[s.Name][s.Version].Nodes[n.ID].LastSeen = time.Now() } } m.records[options.Domain] = srvs return nil } func (m *memory) Deregister(ctx context.Context, s *Service, opts ...DeregisterOption) error { m.Lock() defer m.Unlock() options := NewDeregisterOptions(opts...) // domain is set in metadata so it can be passed to watchers if s.Metadata == nil { s.Metadata = map[string]string{"domain": options.Domain} } else { s.Metadata["domain"] = options.Domain } // if the domain doesn't exist, there is nothing to deregister services, ok := m.records[options.Domain] if !ok { return nil } // if no services with this name and version exist, there is nothing to deregister versions, ok := services[s.Name] if !ok { return nil } version, ok := versions[s.Version] if !ok { return nil } // deregister all of the service nodes from this version for _, n := range s.Nodes { if _, ok := version.Nodes[n.ID]; ok { if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register removed node from service: %s, version: %s", s.Name, s.Version) } delete(version.Nodes, n.ID) } } // if the nodes not empty, we replace the version in the store and exist, the rest of the logic // is cleanup if len(version.Nodes) > 0 { m.records[options.Domain][s.Name][s.Version] = version go m.sendEvent(&Result{Action: "update", Service: s}) return nil } // if this version was the only version of the service, we can remove the whole service from the // register and exit if len(versions) == 1 { delete(m.records[options.Domain], s.Name) go m.sendEvent(&Result{Action: "delete", Service: s}) if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register removed service: %s", s.Name) } return nil } // there are other versions of the service running, so only remove this version of it delete(m.records[options.Domain][s.Name], s.Version) go m.sendEvent(&Result{Action: "delete", Service: s}) if m.opts.Logger.V(logger.DebugLevel) { m.opts.Logger.Debugf(m.opts.Context, "Register removed service: %s, version: %s", s.Name, s.Version) } return nil } func (m *memory) LookupService(ctx context.Context, name string, opts ...LookupOption) ([]*Service, error) { options := NewLookupOptions(opts...) // if it's a wildcard domain, return from all domains if options.Domain == WildcardDomain { m.RLock() recs := m.records m.RUnlock() var services []*Service for domain := range recs { srvs, err := m.LookupService(ctx, name, append(opts, LookupDomain(domain))...) if err == ErrNotFound { continue } else if err != nil { return nil, err } services = append(services, srvs...) } if len(services) == 0 { return nil, ErrNotFound } return services, nil } m.RLock() defer m.RUnlock() // check the domain exists services, ok := m.records[options.Domain] if !ok { return nil, ErrNotFound } // check the service exists versions, ok := services[name] if !ok || len(versions) == 0 { return nil, ErrNotFound } // serialize the response result := make([]*Service, len(versions)) var i int for _, r := range versions { result[i] = recordToService(r, options.Domain) i++ } return result, nil } func (m *memory) ListServices(ctx context.Context, opts ...ListOption) ([]*Service, error) { options := NewListOptions(opts...) // if it's a wildcard domain, list from all domains if options.Domain == WildcardDomain { m.RLock() recs := m.records m.RUnlock() var services []*Service for domain := range recs { srvs, err := m.ListServices(ctx, append(opts, ListDomain(domain))...) if err != nil { return nil, err } services = append(services, srvs...) } return services, nil } m.RLock() defer m.RUnlock() // ensure the domain exists services, ok := m.records[options.Domain] if !ok { return make([]*Service, 0), nil } // serialize the result, each version counts as an individual service var result []*Service for _, service := range services { for _, version := range service { result = append(result, recordToService(version, options.Domain)) } } return result, nil } func (m *memory) Watch(ctx context.Context, opts ...WatchOption) (Watcher, error) { id, err := id.New() if err != nil { return nil, err } wo := NewWatchOptions(opts...) // construct the watcher w := &watcher{ exit: make(chan bool), res: make(chan *Result), id: id, wo: wo, } m.Lock() m.watchers[w.id] = w m.Unlock() return w, nil } func (m *memory) Name() string { return m.opts.Name } func (m *memory) String() string { return "memory" } type watcher struct { res chan *Result exit chan bool wo WatchOptions id string } func (m *watcher) Next() (*Result, error) { for { select { case r := <-m.res: if r.Service == nil { continue } if len(m.wo.Service) > 0 && m.wo.Service != r.Service.Name { continue } // extract domain from service metadata var domain string if r.Service.Metadata != nil && len(r.Service.Metadata["domain"]) > 0 { domain = r.Service.Metadata["domain"] } else { domain = DefaultDomain } // only send the event if watching the wildcard or this specific domain if m.wo.Domain == WildcardDomain || m.wo.Domain == domain { return r, nil } case <-m.exit: return nil, errors.New("watcher stopped") } } } func (m *watcher) Stop() { select { case <-m.exit: return default: close(m.exit) } } func serviceToRecord(s *Service, ttl time.Duration) *record { metadata := make(map[string]string, len(s.Metadata)) for k, v := range s.Metadata { metadata[k] = v } nodes := make(map[string]*node, len(s.Nodes)) for _, n := range s.Nodes { nodes[n.ID] = &node{ Node: n, TTL: ttl, LastSeen: time.Now(), } } endpoints := make([]*Endpoint, len(s.Endpoints)) for i, e := range s.Endpoints { endpoints[i] = e } return &record{ Name: s.Name, Version: s.Version, Metadata: metadata, Nodes: nodes, Endpoints: endpoints, } } func recordToService(r *record, domain string) *Service { metadata := make(map[string]string, len(r.Metadata)) for k, v := range r.Metadata { metadata[k] = v } // set the domain in metadata so it can be determined when a wildcard query is performed metadata["domain"] = domain endpoints := make([]*Endpoint, len(r.Endpoints)) for i, e := range r.Endpoints { md := make(map[string]string, len(e.Metadata)) for k, v := range e.Metadata { md[k] = v } endpoints[i] = &Endpoint{ Name: e.Name, Request: e.Request, Response: e.Response, Metadata: md, } } nodes := make([]*Node, len(r.Nodes)) i := 0 for _, n := range r.Nodes { md := make(map[string]string, len(n.Metadata)) for k, v := range n.Metadata { md[k] = v } nodes[i] = &Node{ ID: n.ID, Address: n.Address, Metadata: md, } i++ } return &Service{ Name: r.Name, Version: r.Version, Metadata: metadata, Endpoints: endpoints, Nodes: nodes, } }