func()

in datasource/mongo/ms.go [1012:1071]
55 lines of code
9 McCabe index (conditional complexity)

func (ds *MetadataManager) ListInstance(ctx context.Context, request *discovery.GetInstancesRequest) (*discovery.GetInstancesResponse, error) {
	service := &model.Service{}
	var err error

	if len(request.ConsumerServiceId) > 0 {
		service, err = GetServiceByID(ctx, request.ConsumerServiceId)
		if err != nil {
			if errors.Is(err, datasource.ErrNoData) {
				log.Debug(fmt.Sprintf("consumer does not exist, consumer %s find provider %s instances",
					request.ConsumerServiceId, request.ProviderServiceId))
				return nil, discovery.NewError(discovery.ErrServiceNotExists,
					fmt.Sprintf("Consumer[%s] does not exist.", request.ConsumerServiceId))
			}
			log.Error(fmt.Sprintf("get consumer failed, consumer %s find provider %s instances",
				request.ConsumerServiceId, request.ProviderServiceId), err)
			return nil, discovery.NewError(discovery.ErrInternal, err.Error())
		}
	}

	provider, err := GetServiceByID(ctx, request.ProviderServiceId)
	if err != nil {
		if errors.Is(err, datasource.ErrNoData) {
			log.Debug(fmt.Sprintf("provider does not exist, consumer %s find provider %s  instances",
				request.ConsumerServiceId, request.ProviderServiceId))
			return nil, discovery.NewError(discovery.ErrServiceNotExists,
				fmt.Sprintf("provider[%s] does not exist.", request.ProviderServiceId))
		}
		log.Error(fmt.Sprintf("get provider failed, consumer %s find provider instances %s",
			request.ConsumerServiceId, request.ProviderServiceId), err)
		return nil, discovery.NewError(discovery.ErrInternal, err.Error())
	}

	findFlag := func() string {
		return fmt.Sprintf("consumer[%s][%s/%s/%s/%s] find provider[%s][%s/%s/%s/%s] instances",
			request.ConsumerServiceId, service.Service.Environment, service.Service.AppId, service.Service.ServiceName, service.Service.Version,
			provider.Service.ServiceId, provider.Service.Environment, provider.Service.AppId, provider.Service.ServiceName, provider.Service.Version)
	}

	rev, _ := ctx.Value(util.CtxRequestRevision).(string)
	serviceIDs := filterServiceIDs(ctx, request.ConsumerServiceId, request.Tags, []*model.Service{provider})
	if len(serviceIDs) == 0 {
		mes := fmt.Errorf("%s failed, provider does not exist", findFlag())
		log.Error("query service failed", mes)
		return nil, discovery.NewError(discovery.ErrServiceNotExists, mes.Error())
	}

	instances, err := GetAllInstancesOfOneService(ctx, request.ProviderServiceId)
	if err != nil {
		log.Error(fmt.Sprintf("get instances failed %s", findFlag()), err)
		return nil, discovery.NewError(discovery.ErrInternal, err.Error())
	}
	newRev, _ := formatRevision(request.ConsumerServiceId, instances)
	if rev == newRev {
		instances = nil // for gRPC
	}
	_ = util.WithResponseRev(ctx, newRev)
	return &discovery.GetInstancesResponse{
		Instances: instances,
	}, nil
}