quick start for template content - Resource Orchestration Service

A template is a blueprint that defines cloud service resources and their dependencies for deployment through Resource Orchestration Service (ROS). This example walks you through writing a template that creates a virtual private cloud (VPC) and a vSwitch.

Prerequisites

You are familiar with the requirements on template structures. For more information, see Template structure.

Select a template editor

You can use an online or on-premises template editor. Both support automatic syntax hinting and resource property validation.

Online editor: Requires no installation and is suitable for simple resource deployment templates. For more information, see Write templates with the ROS online editor.

Define a template

To define a template, declare the resources you want to create in the Resources section. See Resource type index for all supported resource types. The documentation for each resource type lists supported properties and return values, including whether a property is required or editable. Required properties must be declared in the Properties part of the Resources section. Editable properties can be modified via a stack update; non-editable properties cannot be changed after creation.

View details of the desired resource types.
1. Refer to Resource type index to find the resource types that are suitable for your deployment scenario. In this example, the ALIYUN::ECS::VPC and ALIYUN::ECS::VSwitch resource types that are used to create a VPC and a vSwitch are suitable.
2. Refer to the documentation of each resource type and view the resource properties.

In the Parameters section, define the parameters of the template.

Define VpcCidrBlock for the VPC, and ZoneId, VSwitchName, and VSwitchCidrBlock for the vSwitch. Parameters in this section appear as GUI elements in the ROS console. For more information, see ALIYUN::ECS::VPC and ALIYUN::ECS::VSwitch. The vSwitch CIDR block must fall within the VPC CIDR block.

Parameters:
  VpcCidrBlock:
    Type: String
    Default: 192.168.0.0/16
    AllowedValues:
      - 10.0.0.0/8
      - 172.16.0.0/12
      - 192.168.0.0/16
  ZoneId:
    Type: String
    AssociationProperty: ALIYUN::ECS::Instance::ZoneId
  VSwitchName:
    Type: String
  VSwitchCidrBlock:
    Type: String
    Default: 192.168.0.0/24
    AllowedValues:
      - 10.0.0.0/24
      - 172.16.0.0/24
      - 192.168.0.0/24

In the Resources section, define the resources that you want to create.

VpcId, ZoneId, and CidrBlock are required for the vSwitch. Other properties are optional. For more information, see ALIYUN::ECS::VPC and ALIYUN::ECS::VSwitch. Use the Ref function to reference parameters, or specify values directly. For more information, see Ref.

Resources:
  Vpc:
    Type: ALIYUN::ECS::VPC
    Properties:
      VpcName: MyTest
      CidrBlock:
        Ref: VpcCidrBlock 
  VSwitch:
    Type: ALIYUN::ECS::VSwitch
    Properties:
      VpcId:
        Ref: Vpc
      ZoneId:
        Ref: ZoneId
      VSwitchName:
        Ref: VSwitchName
      CidrBlock:
        Ref: VSwitchCidrBlock

In the Outputs section, define the outputs of the template.

Define VpcId and VSwitchId as outputs. For more information, see ALIYUN::ECS::VPC and ALIYUN::ECS::VSwitch. Use the Fn::GetAtt function to retrieve resource property values. For more information, see Fn::GetAtt.
```
Outputs:
  VpcId:
    Value:
      Fn::GetAtt:
        - Vpc
        - VpcId
  VSwitchId:
    Value:
      Fn::GetAtt:
        - VSwitch
        - VSwitchId
```

Follow the template structure to define the complete template content.

ROSTemplateFormatVersion: '2015-09-01'
Parameters:
  VSwitchName:
    Type: String
  VSwitchCidrBlock:
    Default: 192.168.0.0/24
    Type: String
    AllowedValues:
      - 10.0.0.0/24
      - 172.16.0.0/24
      - 192.168.0.0/24
  VpcCidrBlock:
    Default: 192.168.0.0/16
    Type: String
    AllowedValues:
      - 10.0.0.0/8
      - 172.16.0.0/12
      - 192.168.0.0/16
  ZoneId:
    AssociationProperty: ALIYUN::ECS::Instance::ZoneId
    Type: String
Resources:
  VSwitch:
    Type: ALIYUN::ECS::VSwitch
    Properties:
      VSwitchName:
        Ref: VSwitchName
      VpcId:
        Ref: Vpc
      CidrBlock:
        Ref: VSwitchCidrBlock
      ZoneId:
        Ref: ZoneId
  Vpc:
    Type: ALIYUN::ECS::VPC
    Properties:
      VpcName: MyTest
      CidrBlock:
        Ref: VpcCidrBlock
Outputs:
  VpcId:
    Value:
      Fn::GetAtt:
        - Vpc
        - VpcId
  VSwitchId:
    Value:
      Fn::GetAtt:
        - VSwitch
        - VSwitchId

What to do next

Use the defined template to create a stack or save the template as your private template. For more information, see Stack quick start and Create a template.

References

Configure advanced template settings:
- Get started with ROS templates: describes how to create a template.
- Metadata: describes how to define the visualized layout of a template.
- Mappings: describes how to define the mappings of a template.
- Conditions and Functions: describe how to define conditions by using built-in functions.
- Rules: describes how to define the rules of a template.
Template best practices: