Using stack and launch outputs

What are we going to do?

This tutorial will walk you through how to use the “Using stack and launch outputs” feature.

We will assume you have:

  • installed Service Catalog Puppet correctly
  • bootstrapped a spoke
  • created a manifest file
  • added an account to the manifest file

We will assume you are comfortable:

  • making changes your portfolios files
  • making changes your manifest file
  • provisioning stacks
  • provisioning products / launches

Step by step guide

Here are the steps you need to follow to “Using stack and launch outputs”

Things to note, before we start

  • The cloudformation_stack_output feature was added in version 0.150.0 of Service Catalog Puppet. You will need to be using this version (or later)
  • The servicecatalog_provisioned_product_output feature was added in version 0.160.0 of Service Catalog Puppet. You will need to be using this version (or later)

Provision a stack with some outputs

In order to use a stack output you must first provision a stack that provides the output. Here is an example of such a template:

Parameters:
  CidrBlock:
    Type: String
  Name:
    Type: String

Resources:
  VPC:
    Type: AWS::EC2::VPC
    Properties:
      CidrBlock: !Ref CidrBlock
      EnableDnsHostnames: True
      EnableDnsSupport: True
      Tags:
        - Key: Name
          Value: !Ref Name
Outputs:
  VpcId:
    Value: !Ref VPC
    Description: Output VPC ID for utilisation by dependent product
  VpcCidrBlock:
    Value: !GetAtt VPC.CidrBlock

Here we are provisioning a stack that outputs VpcId as an output.

Provisioning a stack that depends on the initial stack, which consumes stack outputs

Once you have provisioned the stack that provides the output you will need to define a stack that uses the output:

Parameters:
  CidrBlock:
    Type: String
  VpcId:
    Type: String

Resources:
  Subnet:
    Type: AWS::EC2::Subnet
    Properties:
      CidrBlock: !Select [ 0, !Cidr [ !Ref CidrBlock, 6, 5 ]]
      AvailabilityZone: !Select
        - 0
        - Fn::GetAZs: !Ref "AWS::Region"
      Tags:
        - Key: Name
          Value: "Example-Subnet-AZ1"
      VpcId: !Ref VpcId

Here we are defining a stack that uses VpcId as a parameter.

Provision a stack using Service Catalog Puppet

Now we are ready to provision the stack using the manifest file.

To use the output from one stack as a parameter for another you can use the following syntax:

stacks:
  example-subnet:
    name: example-subnet
    version: v1
    depends_on:
      - example-vpc
    parameters:
      CidrBlock:
        cloudformation_stack_output:
          account_id: ${AWS::AccountId}
          region: ${AWS::Region}
          stack_name: example-vpc
          output_key: VpcCidrBlock
      VpcId:
        cloudformation_stack_output:
          account_id: ${AWS::AccountId}
          region: ${AWS::Region}
          stack_name: example-vpc
          output_key: VpcId
    deploy_to:
      tags:
        - tag: type:prod
          regions: regions_enabled

In this example we are reading VpcCidrBlock and VpcId from the stack named example-vpc when provisioning the stack named example-subnet.

Working with ServiceCatalog Provisioned product outputs

If you would like to obtain the output of a provisioned product deployment, it is possible to call the servicecatalog_provisioned_product_output method to obtain stack outputs. In the example below we are calling from the output of a launch called ‘example-vpc’

stacks:
  example-subnet:
    name: example-subnet
    version: v1
    depends_on:
      - example-vpc
    parameters:
      CidrBlock:
        servicecatalog_provisioned_product_output:
          account_id: ${AWS::AccountId}
          region: ${AWS::Region}
          provisioned_product_name: example-vpc
          output_key: VpcCidrBlock
      VpcId:
        servicecatalog_provisioned_product_output:
          account_id: ${AWS::AccountId}
          region: ${AWS::Region}
          provisioned_product_name: example-vpc
          output_key: VpcId
    deploy_to:
      tags:
        - tag: type:prod
          regions: regions_enabled