code: func New(addr string, store Store, credentials CredentialStore) *Service {
  	return &Service{
  		addr:            addr,
  		store:           store,
  		start:           time.Now(),
  		statuses:        make(map[string]Statuser),
  		credentialStore: credentials,
  		logger:          log.New(os.Stderr, "[http] ", log.LstdFlags),
  	}
  }
docs: // New returns an uninitialized HTTP service. If credentials is nil, then
  // the service performs no authentication and authorization checks.