func (service ServiceTx) EndpointRelation(endpointID portainer.EndpointID) (*portainer.EndpointRelation, error) {
    var endpointRelation portainer.EndpointRelation
    identifier := service.service.connection.ConvertToKey(int(endpointID))

    err := service.tx.GetObject(BucketName, identifier, &endpointRelation)