func()

in datasource/etcd/ms.go [642:707]
57 lines of code
12 McCabe index (conditional complexity)

func (ds *MetadataManager) findInstance(ctx context.Context, request *pb.FindInstancesRequest,
	provider *pb.MicroServiceKey, rev string) (*pb.FindInstancesResponse, error) {
	var err error
	domainProject := util.ParseDomainProject(ctx)
	service := &pb.MicroService{Environment: request.Environment}
	if len(request.ConsumerServiceId) > 0 {
		service, err = eutil.GetService(ctx, domainProject, request.ConsumerServiceId)
		if err != nil {
			if errors.Is(err, datasource.ErrNoData) {
				log.Debug(fmt.Sprintf("consumer does not exist, consumer[%s] find provider[%s/%s/%s]",
					request.ConsumerServiceId, request.Environment, request.AppId, request.ServiceName))
				return nil, pb.NewError(pb.ErrServiceNotExists,
					fmt.Sprintf("Consumer[%s] does not exist.", request.ConsumerServiceId))
			}
			log.Error(fmt.Sprintf("get consumer failed, consumer[%s] find provider[%s/%s/%s]",
				request.ConsumerServiceId, request.Environment, request.AppId, request.ServiceName), err)
			return nil, pb.NewError(pb.ErrInternal, err.Error())
		}
		provider.Environment = service.Environment
	}

	// provider is not a shared micro-service,
	// only allow shared micro-service instances found request different domains.
	ctx = util.SetTargetDomainProject(ctx, util.ParseDomain(ctx), util.ParseProject(ctx))
	provider.Tenant = util.ParseTargetDomainProject(ctx)

	findFlag := fmt.Sprintf("Consumer[%s][%s/%s/%s/%s] find provider[%s/%s/%s]",
		request.ConsumerServiceId, service.Environment, service.AppId, service.ServiceName, service.Version,
		provider.Environment, provider.AppId, provider.ServiceName)

	// cache
	var item *cache.VersionRuleCacheItem
	item, err = cache.FindInstances.Get(ctx, service, provider, request.Tags, rev)
	if err != nil {
		log.Error(fmt.Sprintf("FindInstancesCache.Get failed, %s failed", findFlag), err)
		return nil, pb.NewError(pb.ErrInternal, err.Error())
	}
	if item == nil {
		err := fmt.Errorf("%s failed, provider does not exist", findFlag)
		log.Error("FindInstancesCache.Get failed", err)
		return nil, pb.NewError(pb.ErrServiceNotExists, err.Error())
	}

	// add dependency queue
	if len(request.ConsumerServiceId) > 0 &&
		len(item.ServiceIds) > 0 &&
		!cache.DependencyRule.ExistRule(ctx, request.ConsumerServiceId, provider) {
		provider, err = ds.reshapeProviderKey(ctx, provider, item.ServiceIds[0])
		if err != nil {
			return nil, err
		}
		if provider != nil {
			err = eutil.AddServiceVersionRule(ctx, domainProject, service, provider)
		} else {
			err := fmt.Errorf("%s failed, provider does not exist", findFlag)
			log.Error("AddServiceVersionRule failed", err)
			return nil, pb.NewError(pb.ErrServiceNotExists, err.Error())
		}
		if err != nil {
			log.Error(fmt.Sprintf("AddServiceVersionRule failed, %s failed", findFlag), err)
			return nil, pb.NewError(pb.ErrInternal, err.Error())
		}
	}

	return ds.genFindResult(ctx, rev, item)
}