Amazon Rekognition Verify a Face Against a Collection

arazzo: 1.0.1
info:
  title: Amazon Rekognition Verify a Face Against a Collection
  summary: Detect a face in an image to confirm a single subject, then search a collection to verify identity.
  description: >-
    A face-verification flow for Amazon Rekognition. The workflow first runs
    DetectFaces against the probe image to confirm a face is present and capture
    its quality attributes, then performs a SearchFacesByImage against an
    existing collection to verify whether the probe matches an enrolled
    identity. Each step spells out its AWS JSON 1.1 request inline, including the
    protocol-required X-Amz-Target header.
  version: 1.0.0
sourceDescriptions:
- name: rekognitionApi
  url: ../openapi/amazon-rekognition-openapi.yml
  type: openapi
workflows:
- workflowId: verify-face-against-collection
  summary: Detect a probe face then search a collection to verify identity.
  description: >-
    Confirms a face exists in the probe image and then searches an existing
    collection by that image to verify the subject against enrolled faces.
  inputs:
    type: object
    required:
    - collectionId
    - probeBucket
    - probeName
    properties:
      collectionId:
        type: string
        description: ID of the collection holding enrolled faces.
      probeBucket:
        type: string
        description: S3 bucket holding the probe image to verify.
      probeName:
        type: string
        description: S3 object key of the probe image.
      faceMatchThreshold:
        type: number
        description: Minimum confidence for a verification match.
        default: 90.0
  steps:
  - stepId: detectFaces
    description: Detect faces in the probe image and return all facial attributes.
    operationId: detectFaces
    parameters:
    - name: X-Amz-Target
      in: header
      value: RekognitionService.DetectFaces
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        Image:
          S3Object:
            Bucket: $inputs.probeBucket
            Name: $inputs.probeName
        Attributes:
        - ALL
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      faceDetails: $response.body#/FaceDetails
    onSuccess:
    - name: faceFound
      type: goto
      stepId: searchByImage
      criteria:
      - context: $response.body
        condition: $.FaceDetails[0] empty false
        type: jsonpath
  - stepId: searchByImage
    description: Search the collection for faces matching the probe image to verify identity.
    operationId: searchFacesByImage
    parameters:
    - name: X-Amz-Target
      in: header
      value: RekognitionService.SearchFacesByImage
    requestBody:
      contentType: application/x-amz-json-1.1
      payload:
        CollectionId: $inputs.collectionId
        Image:
          S3Object:
            Bucket: $inputs.probeBucket
            Name: $inputs.probeName
        MaxFaces: 1
        FaceMatchThreshold: $inputs.faceMatchThreshold
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      faceMatches: $response.body#/FaceMatches
      searchedFaceConfidence: $response.body#/SearchedFaceConfidence
  outputs:
    faceDetails: $steps.detectFaces.outputs.faceDetails
    faceMatches: $steps.searchByImage.outputs.faceMatches