Amazon Kinesis Scale Stream Shard Count

arazzo: 1.0.1
info:
  title: Amazon Kinesis Scale Stream Shard Count
  summary: Resize a provisioned stream's shard count, wait for ACTIVE, then list shards.
  description: >-
    Scales a provisioned-mode stream up or down. UpdateShardCount initiates a
    uniform-scaling resize and the stream transitions to UPDATING; the workflow
    polls DescribeStreamSummary, looping while UPDATING and proceeding once the
    stream returns to ACTIVE, then lists the resulting shards with ListShards to
    confirm the new topology. Each step inlines its AWS JSON protocol request,
    including the required X-Amz-Target header, so the flow can be read and
    executed without opening the underlying OpenAPI description.
  version: 1.0.0
sourceDescriptions:
- name: shardsApi
  url: ../openapi/amazon-kinesis-shards-api-openapi.yml
  type: openapi
- name: streamsApi
  url: ../openapi/amazon-kinesis-streams-api-openapi.yml
  type: openapi
workflows:
- workflowId: scale-stream-shard-count
  summary: Update shard count, poll until ACTIVE, then list the new shards.
  description: >-
    Calls UpdateShardCount with UNIFORM_SCALING to the target count, polls
    DescribeStreamSummary while UPDATING, and once ACTIVE lists the shards to
    confirm the resize.
  inputs:
    type: object
    required:
    - streamName
    - targetShardCount
    properties:
      streamName:
        type: string
        description: The name of the provisioned Kinesis data stream to resize.
      targetShardCount:
        type: integer
        description: The new number of shards for the stream.
  steps:
  - stepId: updateShardCount
    description: >-
      Initiate a uniform-scaling resize to the target shard count. The stream
      transitions to UPDATING.
    operationId: UpdateShardCount
    parameters:
    - name: X-Amz-Target
      in: header
      value: Kinesis_20131202.UpdateShardCount
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        StreamName: $inputs.streamName
        TargetShardCount: $inputs.targetShardCount
        ScalingType: UNIFORM_SCALING
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      currentShardCount: $response.body#/CurrentShardCount
      targetShardCount: $response.body#/TargetShardCount
  - stepId: pollStatus
    description: >-
      Poll the stream summary, looping while UPDATING and advancing once the
      stream is ACTIVE again.
    operationId: DescribeStreamSummary
    parameters:
    - name: X-Amz-Target
      in: header
      value: Kinesis_20131202.DescribeStreamSummary
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        StreamName: $inputs.streamName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      streamStatus: $response.body#/StreamDescriptionSummary/StreamStatus
      openShardCount: $response.body#/StreamDescriptionSummary/OpenShardCount
    onSuccess:
    - name: stillUpdating
      type: goto
      stepId: pollStatus
      criteria:
      - context: $response.body
        condition: $.StreamDescriptionSummary.StreamStatus == "UPDATING"
        type: jsonpath
    - name: nowActive
      type: goto
      stepId: listShards
      criteria:
      - context: $response.body
        condition: $.StreamDescriptionSummary.StreamStatus == "ACTIVE"
        type: jsonpath
  - stepId: listShards
    description: >-
      List the shards after the resize completes to confirm the new shard
      topology.
    operationId: ListShards
    parameters:
    - name: X-Amz-Target
      in: header
      value: Kinesis_20131202.ListShards
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        StreamName: $inputs.streamName
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      shards: $response.body#/Shards
  outputs:
    openShardCount: $steps.pollStatus.outputs.openShardCount
    shards: $steps.listShards.outputs.shards