Why perform a parameter constraint query - Resource Orchestration Service

You can use the parameter constraint query feature to obtain the values of parameters that are defined in a template.

Background information

When you use AssociationProperty and AssociationPropertyMetadata to filter parameters, the filtered parameters may not meet your requirements in specific scenarios.

For example, the ZoneId parameter is supported by multiple Alibaba Cloud services, but its valid values differ between services. In this case, you can perform a parameter constraint query to obtain the value of the ZoneId parameter defined in your template.

Supported properties

If a property of a resource type is referenced by a parameter by using the Ref function, you can call the GetTemplateParameterConstraints operation to obtain the property value. The following table lists all properties that support the parameter constraint query feature and the corresponding resource types.
You can call the GetFeatureDetails operation to obtain the resource types whose properties support the parameter constraint query feature.

Note

The template from which you want to query parameter contraints must contain the Parameters section.

Resource type	Property	Description
ALIYUN::ADB::DBCluster	ZoneId	None.
ALIYUN::ALB::LoadBalancer	ZoneId in ZoneMappings	None.
ALIYUN::AMQP::Instance	PeriodUnit Period	None.
ALIYUN::ApiGateway::Instance	PricingCycle Duration	None.
ALIYUN::CDDC::DedicatedHost	Period UsedTime	None.
ALIYUN::CEN::CenBandwidthPackage	PricingCycle Period	None.
ALIYUN::ClickHouse::DBCluster	Period ZoneId UsedTime	None.
ALIYUN::CloudPhone::InstanceGroup	PeriodUnit Period	None.
ALIYUN::CS::AnyCluster	PeriodUnit Period MasterInstanceTypes WorkerZoneIds PodVswitchIds WorkerSystemDiskCategory MasterZoneIds WorkerVSwitchIds KubernetesVersion WorkerInstanceTypes ScalingGroup.SystemDiskCategory in NodePools ScalingGroup.ZoneIds in NodePools ScalingGroup.InstanceTypes in NodePools MasterSystemDiskCategory Category in WorkerDataDisks Category in MasterDataDisks Category in ScalingGroup.DataDisks of NodePools	None.
ALIYUN::CS::ClusterNodePool	PeriodUnit in ScalingGroup Period in ScalingGroup InstanceTypes in ScalingGroup ZoneIds in ScalingGroup Category in ScalingGroup.DataDisks SystemDiskCategory in ScalingGroup	None.
ALIYUN::CS::KubernetesCluster	MasterInstanceTypes MasterSystemDiskCategory WorkerInstanceTypes WorkerSystemDiskCategory WorkerVSwitchIds PodVswitchIds KubernetesVersion PeriodUnit WorkerZoneIds Period MasterZoneIds ScalingGroup.InstanceTypes in NodePools Category in ScalingGroup.DataDisks of NodePools ScalingGroup.ZoneIds in NodePools ScalingGroup.SystemDiskCategory in NodePools Category in MasterDataDisks Category in WorkerDataDisks	None.
ALIYUN::CS::ManagedEdgeKubernetesCluster	WorkerInstanceTypes PeriodUnit Period ZoneIds VSwitchIds WorkerSystemDiskCategory WorkerDataDiskCategory	None.
ALIYUN::CS::ManagedKubernetesCluster	WorkerInstanceTypes WorkerSystemDiskCategory VSwitchIds PodVswitchIds KubernetesVersion PeriodUnit Period ZoneIds ScalingGroup.ZoneIds in NodePools ScalingGroup.InstanceTypes in NodePools Category in ScalingGroup.DataDisks of NodePools Category in WorkerDataDisks ScalingGroup.SystemDiskCategory in NodePools	None.
ALIYUN::CS::ServerlessKubernetesCluster	PeriodUnit Period KubernetesVersion	None.
ALIYUN::DRDS::DrdsInstance	PricingCycle Duration	None.
ALIYUN::DTS::SubscriptionInstance	Period UsedTime	None.
ALIYUN::DTS::SynchronizationJob	Period UsedTime	None.
ALIYUN::ECD::Desktops	PeriodUnit Period	None.
ALIYUN::ECS::DedicatedHost	PeriodUnit Period	None.
ALIYUN::ECS::Disk	DiskCategory ZoneId	None.
ALIYUN::ECS::Instance	ZoneId PeriodUnit InstanceType Period SystemDiskCategory Category in DiskMappings	None.
ALIYUN::ECS::InstanceGroup	ZoneId PeriodUnit InstanceType Period SystemDiskCategory Category in DiskMappings	None.
ALIYUN::ECS::InstanceGroupClone	PeriodUnit Period SystemDiskCategory Category in DiskMappings PeriodUnit Period InstanceType ZoneId	None.
ALIYUN::ECS::PrepayInstance	PeriodUnit Period SystemDiskCategory Category in DiskMappings PeriodUnit Period InstanceType ZoneId	None.
ALIYUN::ECS::PrepayInstanceGroupClone	PeriodUnit Period SystemDiskCategory Category in DiskMappings PeriodUnit Period InstanceType ZoneId	None.
ALIYUN::ECS::VSwitch	ZoneId Period PeriodType	None.
ALIYUN::EHPC::Cluster	PeriodUnit Period EcsOrderManagerInstanceType EcsOrderComputeInstanceType EcsOrderLoginInstanceType SystemDiskType ZoneId	None.
ALIYUN::ElasticSearch::Instance	PeriodUnit ZoneId Period Spec in DataNode Spec in MasterNode Spec in KibanaNode	You can query specifications only by zone.
ALIYUN::EMR::Cluster	DiskType in HostGroup NetType SysDiskType in HostGroup InstanceType in HostGroup ZoneId	None.
ALIYUN::Flink::Instance	PricingCycle Duration ZoneId	None.
ALIYUN::GA::Accelerator	PricingCycle Duration	None.
ALIYUN::GA::BandwidthPackage	PricingCycle Duration	None.
ALIYUN::GPDB::DBInstance	ZoneId PeriodUnit Period	None.
ALIYUN::GPDB::ElasticDBInstance	ZoneId EngineVersion InstanceSpec DBInstanceCategory SegStorageType	None.
ALIYUN::GWS::Instance	PeriodUnit Period	None.
ALIYUN::MONGODB::Instance	StorageType DBInstanceClass EngineVersion ZoneId	None.
ALIYUN::MONGODB::PrepayInstance	StorageType DBInstanceClass EngineVersion ZoneId	None.
ALIYUN::MONGODB::ServerlessInstance	StorageType DBInstanceClass EngineVersion ZoneId	None.
ALIYUN::MONGODB::ShardingInstance	StorageType DBInstanceClass EngineVersion ZoneId	None.
ALIYUN::NAS::FileSystem	ProtocolType StorageType ZoneId	None.
ALIYUN::POLARDB::DBCluster	ZoneId Duration PricingCycle DBNodeClass	None.
ALIYUN::PrivateLink::VpcEndpointService	ZoneId in Resource	None.
ALIYUN::RDS::DBInstance	ZoneId Period PeriodType EngineVersion Category DBInstanceStorageType DBInstanceClass	Note To ensure complete validation, you must specify ZoneId, DBInstanceStorageType, and Category. To ensure complete validation, you must set MultiAZ to false. To ensure complete validation, you must place the parameters related to the Engine property of ApsaraDB RDS before the parameters related to other ApsaraDB RDS properties when you use Metadata to specify the parameter order.
ALIYUN::RDS::DBInstanceClone	PeriodType Period Category EngineVersion PeriodType DBInstanceClass DBInstanceStorageType Period ZoneId	Note To ensure complete validation, you must specify ZoneId, DBInstanceStorageType, and Category. To ensure complete validation, you must set MultiAZ to false. To ensure complete validation, you must place the parameters related to the Engine property of ApsaraDB RDS before the parameters related to other ApsaraDB RDS properties when you use Metadata to specify the parameter order.
ALIYUN::RDS::PrepayDBInstance	ZoneId EngineVersion Category DBInstanceStorageType DBInstanceClass Period PeriodType	Note To ensure complete validation, you must specify ZoneId, DBInstanceStorageType, and Category. To ensure complete validation, you must set MultiAZ to false. To ensure complete validation, you must place the parameters related to the Engine property of ApsaraDB RDS before the parameters related to other ApsaraDB RDS properties when you use Metadata to specify the parameter order.
ALIYUN::RDS::ReadOnlyDBInstance	PeriodType Period Category DBInstanceClass EngineVersion DBInstanceStorageType ZoneId	Note To ensure complete validation, you must specify ZoneId, DBInstanceStorageType, and Category. To ensure complete validation, you must set MultiAZ to false. To ensure complete validation, you must place the parameters related to the Engine property of ApsaraDB RDS before the parameters related to other ApsaraDB RDS properties when you use Metadata to specify the parameter order.
ALIYUN::REDIS::Instance	ZoneId EngineVersion InstanceClass PeriodUnit Period	None.
ALIYUN::REDIS::PrepayInstance	ZoneId Period PeriodUnit EngineVersion InstanceClass	None.
ALIYUN::SLB::AnyTunnel	PricingCycle Duration MasterZoneId SlaveZoneId	None.
ALIYUN::SLB::LoadBalancer	MasterZoneId SlaveZoneId Duration PricingCycle	None.
ALIYUN::TSDB::HiTSDBInstance	InstanceClass ZoneId Duration PricingCycle	None.
ALIYUN::VPC::EIP	PricingCycle Period	None.
ALIYUN::VPC::EIPPro	PricingCycle Period	None.
ALIYUN::VPC::NatGateway	ZoneId Duration PricingCycle	None.
ALIYUN::VPC::RouterInterface	PricingCycle Period	None.

Dependency relationships between parameters

When you use a template to create Elastic Compute Service (ECS) resources in Resource Orchestration Service (ROS), you must specify parameters such as ZoneInfo and InstanceType.

The supported ECS instance types vary based on zones. Therefore, a specific value of the InstanceType parameter may become unavailable after you specify the ZoneInfo parameter.

If you want to use only the specific value of the InstanceType parameter, you can use the Metadata section to configure the dependency relationship between the InstanceType and ZoneInfo parameters.

Note

For more information, see Metadata.

ROSTemplateFormatVersion: '2015-09-01'
Parameters:
  ZoneInfo:
    Type: String
  InstanceType:
    Type: String
Resources:
  ECS:
    Type: ALIYUN::ECS::Instance
    Properties:
      ZoneId:
        Ref: ZoneInfo
      InstanceType:
        Ref: InstanceType
      ImageId: ubuntu
Metadata:
  ALIYUN::ROS::Interface:
    ParameterGroups:
      - Parameters:
          - InstanceType
          - ZoneInfo

Manually configure parameter constraint query for a Terraform template

You can add ResourcesForParameterConstraints to ALIYUN::ROS::Interface in the Metadata section or the .metadata file to configure constraints for parameters.

You must define the resources relevant to the parameter constraints and specify the resource properties. For more information about the syntax of ResourcesForParameterConstraints, see Resources.

The configurations of the Mappings, Conditions, and Rules sections defined in a template automatically take effect during a parameter constraint query. For more information, see (Optional) Mappings, (Optional) Conditions, and (Optional) Rules.

ROSTemplateFormatVersion: '2015-09-01'
Transform: Aliyun::Terraform-v1.1
Workspace:
  .metadata: |-
    {
        "ALIYUN::ROS::Interface": {
            "ResourcesForParameterConstraints": {
                "instance": {
                    "Type": "ALIYUN::ECS::Instance",
                    "Properties": {
                        "ImageId": {
                            "Ref": "image_id"
                        },
                        "InstanceType": {
                            "Ref": "instance_type"
                        },
                        "ZoneId": {
                            "Ref": "zone_id"
                        }
                    }
                }
            },
            "Hidden": [
                "image_id"
            ]
        }
    }
  main.tf: |-
    variable "image_id" {
      type    = string
      default = "ubuntu_18_04_64_20G_alibase_2019****.vhd"
    }

    variable "instance_type" {
      type = string
    }

    variable "zone_id" {
      type = string
    }

    resource "alicloud_vpc" "vpc" {
      cidr_block = "172.16.X.X/16"
    }

    resource "alicloud_security_group" "group" {
      vpc_id = alicloud_vpc.vpc.id
    }

    resource "alicloud_vswitch" "vswitch" {
      vpc_id     = alicloud_vpc.vpc.id
      cidr_block = "172.16.X.X/24"
      zone_id    = var.zone_id
    }

    resource "alicloud_instance" "instance" {
      availability_zone = var.zone_id
      security_groups   = [alicloud_security_group.group.id]
      instance_type     = var.instance_type
      image_id          = var.image_id
      vswitch_id        = alicloud_vswitch.vswitch.id
    }

In the preceding Terraform template, four resources are defined. Constraints are configured for the zone_id and instance_type parameters, and the parameters are associated with alicloud_instance.

In ResourcesForParameterConstraints, only the ALIYUN::ECS::Instance resource type of ROS that corresponds to alicloud_instance is defined. The resource type is associated with the image_id, instance_type, and zone_id parameters to configure constraints for these parameters. In this example, the image_id parameter is hidden.