Amazon Fargate Deploy a Service

arazzo: 1.0.1
info:
  title: Amazon Fargate Deploy a Service
  summary: Register a task definition, create a Fargate service, and poll until the running count meets the desired count.
  description: >-
    Stands up a long-running Fargate service. The workflow registers a
    FARGATE-compatible task definition, creates a service that maintains a
    desired number of tasks behind an awsvpc network configuration, and then
    polls DescribeServices until the running count reaches the desired count.
    Each step inlines its AWS JSON 1.1 request and the X-Amz-Target action
    header so the deployment can be read and executed directly.
  version: 1.0.0
sourceDescriptions:
- name: fargateApi
  url: ../openapi/amazon-fargate-openapi.yml
  type: openapi
workflows:
- workflowId: deploy-service
  summary: Register a task definition and create a Fargate service, then confirm it reaches its desired count.
  description: >-
    Chains registerTaskDefinition and createService, then loops over
    describeServices until runningCount equals desiredCount.
  inputs:
    type: object
    required:
    - cluster
    - family
    - serviceName
    - containerName
    - image
    - desiredCount
    - subnets
    - securityGroups
    properties:
      cluster:
        type: string
        description: Name or ARN of the cluster to deploy into.
      family:
        type: string
        description: Family name for the task definition to register.
      serviceName:
        type: string
        description: Name for the new service.
      containerName:
        type: string
        description: Name of the container in the task definition.
      image:
        type: string
        description: Container image URI.
      cpu:
        type: string
        description: Task-level CPU units for Fargate.
        default: "256"
      memory:
        type: string
        description: Task-level memory in MiB for Fargate.
        default: "512"
      executionRoleArn:
        type: string
        description: ARN of the ECS task execution role.
      desiredCount:
        type: integer
        description: Number of tasks the service should maintain.
      subnets:
        type: array
        items:
          type: string
        description: Subnet IDs for the awsvpc network configuration.
      securityGroups:
        type: array
        items:
          type: string
        description: Security group IDs for the awsvpc network configuration.
      assignPublicIp:
        type: string
        description: Whether to assign a public IP (ENABLED or DISABLED).
        default: ENABLED
  steps:
  - stepId: registerTaskDefinition
    description: Register the FARGATE-compatible task definition the service will run.
    operationId: registerTaskDefinition
    parameters:
    - name: X-Amz-Target
      in: header
      value: AmazonEC2ContainerServiceV20141113.RegisterTaskDefinition
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        family: $inputs.family
        requiresCompatibilities:
        - FARGATE
        networkMode: awsvpc
        cpu: $inputs.cpu
        memory: $inputs.memory
        executionRoleArn: $inputs.executionRoleArn
        containerDefinitions:
        - name: $inputs.containerName
          image: $inputs.image
          essential: true
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      taskDefinitionArn: $response.body#/taskDefinition/taskDefinitionArn
  - stepId: createService
    description: Create the Fargate service that maintains the desired number of tasks.
    operationId: createService
    parameters:
    - name: X-Amz-Target
      in: header
      value: AmazonEC2ContainerServiceV20141113.CreateService
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        cluster: $inputs.cluster
        serviceName: $inputs.serviceName
        taskDefinition: $steps.registerTaskDefinition.outputs.taskDefinitionArn
        desiredCount: $inputs.desiredCount
        launchType: FARGATE
        networkConfiguration:
          awsvpcConfiguration:
            subnets: $inputs.subnets
            securityGroups: $inputs.securityGroups
            assignPublicIp: $inputs.assignPublicIp
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      serviceArn: $response.body#/service/serviceArn
      serviceName: $response.body#/service/serviceName
      serviceStatus: $response.body#/service/status
  - stepId: pollServiceSteady
    description: >-
      Poll DescribeServices until the running count reaches the desired count,
      re-entering this step while the service is still scaling up.
    operationId: describeServices
    parameters:
    - name: X-Amz-Target
      in: header
      value: AmazonEC2ContainerServiceV20141113.DescribeServices
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        cluster: $inputs.cluster
        services:
        - $steps.createService.outputs.serviceName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      runningCount: $response.body#/services/0/runningCount
      desiredCount: $response.body#/services/0/desiredCount
      status: $response.body#/services/0/status
    onSuccess:
    - name: stillScaling
      type: goto
      stepId: pollServiceSteady
      criteria:
      - context: $response.body
        condition: $.services[0].runningCount < $.services[0].desiredCount
        type: jsonpath
    - name: steadyState
      type: end
      criteria:
      - context: $response.body
        condition: $.services[0].runningCount >= $.services[0].desiredCount
        type: jsonpath
  outputs:
    taskDefinitionArn: $steps.registerTaskDefinition.outputs.taskDefinitionArn
    serviceArn: $steps.createService.outputs.serviceArn
    runningCount: $steps.pollServiceSteady.outputs.runningCount
    desiredCount: $steps.pollServiceSteady.outputs.desiredCount