Amazon Elastic Load Balancing Provision an Application Load Balancer

arazzo: 1.0.1
info:
  title: Amazon Elastic Load Balancing Provision an Application Load Balancer
  summary: Stand up an Application Load Balancer with a target group, listener, and registered targets.
  description: >-
    The canonical end-to-end provisioning flow for an Application Load
    Balancer. It creates the load balancer across the supplied subnets,
    creates an HTTP target group in the same VPC, attaches an HTTP listener
    whose default action forwards to that target group, and finally registers
    the initial targets with the group. Each step spells out its request
    inline so the flow can be read and executed without opening the underlying
    OpenAPI description. Because the Elastic Load Balancing v2 API uses the AWS
    query protocol, every operation is a GET whose inputs are carried as query
    parameters rather than a request body.
  version: 1.0.0
sourceDescriptions:
- name: elbv2Api
  url: ../openapi/amazon-elastic-load-balancing-openapi.yml
  type: openapi
workflows:
- workflowId: provision-application-load-balancer
  summary: Create an ALB, a target group, an HTTP listener, and register targets.
  description: >-
    Chains createLoadBalancer, createTargetGroup, createListener, and
    registerTargets so a single run produces a fully wired, traffic-ready
    Application Load Balancer.
  inputs:
    type: object
    required:
    - loadBalancerName
    - subnetId
    - targetGroupName
    - vpcId
    - targetId
    properties:
      loadBalancerName:
        type: string
        description: The unique name for the load balancer (max 32 characters).
      subnetId:
        type: string
        description: The ID of a subnet to place the load balancer in.
      securityGroupId:
        type: string
        description: The ID of a security group for the load balancer.
      targetGroupName:
        type: string
        description: The unique name for the target group.
      vpcId:
        type: string
        description: The ID of the VPC for the target group and targets.
      listenerPort:
        type: integer
        description: The port the listener accepts client connections on.
        default: 80
      targetPort:
        type: integer
        description: The port the targets receive traffic on.
        default: 80
      targetId:
        type: string
        description: The ID of the first target (instance ID, IP, or Lambda ARN).
  steps:
  - stepId: createLoadBalancer
    description: >-
      Create an internet-facing Application Load Balancer in the supplied
      subnet and security group.
    operationId: createLoadBalancer
    parameters:
    - name: Name
      in: query
      value: $inputs.loadBalancerName
    - name: Subnets
      in: query
      value: $inputs.subnetId
    - name: SecurityGroups
      in: query
      value: $inputs.securityGroupId
    - name: Scheme
      in: query
      value: internet-facing
    - name: Type
      in: query
      value: application
    - name: IpAddressType
      in: query
      value: ipv4
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      loadBalancerArn: $response.body#/loadBalancers/0/loadBalancerArn
      dnsName: $response.body#/loadBalancers/0/dnsName
  - stepId: createTargetGroup
    description: >-
      Create an HTTP target group in the same VPC with an HTTP health check on
      the root path.
    operationId: createTargetGroup
    parameters:
    - name: Name
      in: query
      value: $inputs.targetGroupName
    - name: Protocol
      in: query
      value: HTTP
    - name: Port
      in: query
      value: $inputs.targetPort
    - name: VpcId
      in: query
      value: $inputs.vpcId
    - name: HealthCheckProtocol
      in: query
      value: HTTP
    - name: HealthCheckPath
      in: query
      value: /
    - name: TargetType
      in: query
      value: instance
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      targetGroupArn: $response.body#/targetGroups/0/targetGroupArn
  - stepId: createListener
    description: >-
      Attach an HTTP listener whose default action forwards traffic to the new
      target group.
    operationId: createListener
    parameters:
    - name: LoadBalancerArn
      in: query
      value: $steps.createLoadBalancer.outputs.loadBalancerArn
    - name: Protocol
      in: query
      value: HTTP
    - name: Port
      in: query
      value: $inputs.listenerPort
    - name: DefaultActions.member.1.Type
      in: query
      value: forward
    - name: DefaultActions.member.1.TargetGroupArn
      in: query
      value: $steps.createTargetGroup.outputs.targetGroupArn
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      listenerArn: $response.body#/listeners/0/listenerArn
  - stepId: registerTargets
    description: >-
      Register the initial target with the target group so the load balancer
      can begin routing traffic to it.
    operationId: registerTargets
    parameters:
    - name: TargetGroupArn
      in: query
      value: $steps.createTargetGroup.outputs.targetGroupArn
    - name: Targets.member.1.Id
      in: query
      value: $inputs.targetId
    - name: Targets.member.1.Port
      in: query
      value: $inputs.targetPort
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      registered: $statusCode
  outputs:
    loadBalancerArn: $steps.createLoadBalancer.outputs.loadBalancerArn
    dnsName: $steps.createLoadBalancer.outputs.dnsName
    targetGroupArn: $steps.createTargetGroup.outputs.targetGroupArn
    listenerArn: $steps.createListener.outputs.listenerArn