package runtime import ( "errors" "sync" "time" "github.com/micro/go-micro/util/log" ) type runtime struct { sync.RWMutex // options configure runtime options Options // used to stop the runtime closed chan bool // used to start new services start chan *service // indicates if we're running running bool // the service map // TODO: track different versions of the same service services map[string]*service } // NewRuntime creates new local runtime and returns it func NewRuntime(opts ...Option) Runtime { // get default options options := Options{} // apply requested options for _, o := range opts { o(&options) } return &runtime{ options: options, closed: make(chan bool), start: make(chan *service, 128), services: make(map[string]*service), } } // Init initializes runtime options func (r *runtime) Init(opts ...Option) error { r.Lock() defer r.Unlock() for _, o := range opts { o(&r.options) } return nil } // run runs the runtime management loop func (r *runtime) run(events <-chan Event) { t := time.NewTicker(time.Second * 5) defer t.Stop() // process event processes an incoming event processEvent := func(event Event, service *service) error { // get current vals r.RLock() name := service.Name updated := service.updated r.RUnlock() // only process if the timestamp is newer if !event.Timestamp.After(updated) { return nil } log.Debugf("Runtime updating service %s", name) // this will cause a delete followed by created if err := r.Update(service.Service); err != nil { return err } // update the local timestamp r.Lock() service.updated = updated r.Unlock() return nil } for { select { case <-t.C: // check running services r.RLock() for _, service := range r.services { if service.Running() { continue } // TODO: check service error log.Debugf("Runtime starting %s", service.Name) if err := service.Start(); err != nil { log.Debugf("Runtime error starting %s: %v", service.Name, err) } } r.RUnlock() case service := <-r.start: if service.Running() { continue } // TODO: check service error log.Debugf("Runtime starting service %s", service.Name) if err := service.Start(); err != nil { log.Debugf("Runtime error starting service %s: %v", service.Name, err) } case event := <-events: log.Debugf("Runtime received notification event: %v", event) // NOTE: we only handle Update events for now switch event.Type { case Update: if len(event.Service) > 0 { r.RLock() service, ok := r.services[event.Service] r.RUnlock() if !ok { log.Debugf("Runtime unknown service: %s", event.Service) continue } if err := processEvent(event, service); err != nil { log.Debugf("Runtime error updating service %s: %v", event.Service, err) } continue } r.RLock() services := r.services r.RUnlock() // if blank service was received we update all services for _, service := range services { if err := processEvent(event, service); err != nil { log.Debugf("Runtime error updating service %s: %v", service.Name, err) } } } case <-r.closed: log.Debugf("Runtime stopped.") return } } } // Create creates a new service which is then started by runtime func (r *runtime) Create(s *Service, opts ...CreateOption) error { r.Lock() defer r.Unlock() if _, ok := r.services[s.Name]; ok { return errors.New("service already registered") } var options CreateOptions for _, o := range opts { o(&options) } if len(options.Command) == 0 { return errors.New("missing exec command") } // save service r.services[s.Name] = newService(s, options) // push into start queue log.Debugf("Runtime creating service %s", s.Name) r.start <- r.services[s.Name] return nil } // Read returns all instances of requested service // If no service name is provided we return all the track services. func (r *runtime) Read(opts ...ReadOption) ([]*Service, error) { r.Lock() defer r.Unlock() gopts := ReadOptions{} for _, o := range opts { o(&gopts) } save := func(k, v string) bool { if len(k) == 0 { return true } return k == v } var services []*Service for _, service := range r.services { if !save(gopts.Service, service.Name) { continue } if !save(gopts.Version, service.Version) { continue } // TODO deal with service type // no version has sbeen requested, just append the service services = append(services, service.Service) } return services, nil } // Update attemps to update the service func (r *runtime) Update(s *Service) error { var opts []CreateOption // check if the service already exists r.RLock() if service, ok := r.services[s.Name]; ok { opts = append(opts, WithOutput(service.output)) } r.RUnlock() // delete the service if err := r.Delete(s); err != nil { return err } // create new service return r.Create(s, opts...) } // Delete removes the service from the runtime and stops it func (r *runtime) Delete(s *Service) error { r.Lock() defer r.Unlock() log.Debugf("Runtime deleting service %s", s.Name) if s, ok := r.services[s.Name]; ok { // check if running if !s.Running() { delete(r.services, s.Name) return nil } // otherwise stop it if err := s.Stop(); err != nil { return err } // delete it delete(r.services, s.Name) return nil } return nil } // List returns a slice of all services tracked by the runtime func (r *runtime) List() ([]*Service, error) { var services []*Service r.RLock() defer r.RUnlock() for _, service := range r.services { services = append(services, service.Service) } return services, nil } // Start starts the runtime func (r *runtime) Start() error { r.Lock() defer r.Unlock() // already running if r.running { return nil } // set running r.running = true r.closed = make(chan bool) var events <-chan Event if r.options.Notifier != nil { var err error events, err = r.options.Notifier.Notify() if err != nil { // TODO: should we bail here? log.Debugf("Runtime failed to start update notifier") } } go r.run(events) return nil } // Stop stops the runtime func (r *runtime) Stop() error { r.Lock() defer r.Unlock() if !r.running { return nil } select { case <-r.closed: return nil default: close(r.closed) // set not running r.running = false // stop all the services for _, service := range r.services { log.Debugf("Runtime stopping %s", service.Name) service.Stop() } // stop the notifier too if r.options.Notifier != nil { return r.options.Notifier.Close() } } return nil } // String implements stringer interface func (r *runtime) String() string { return "local" }