Paystack Initialize and Verify Transaction

arazzo: 1.0.1
info:
  title: Paystack Initialize and Verify Transaction
  summary: Initialize a checkout transaction and then verify its final status by reference.
  description: >-
    The canonical Paystack accept-payments flow. The workflow initializes a new
    transaction for a customer, captures the authorization URL and reference
    returned by Paystack, and then verifies the transaction by that reference.
    A branch inspects the verified status so success and non-success outcomes can
    be handled distinctly. Every step spells out its request inline so the flow
    can be read and executed without opening the underlying OpenAPI description.
  version: 1.0.0
sourceDescriptions:
- name: transactionApi
  url: ../openapi/paystack-transaction-api-openapi.yml
  type: openapi
workflows:
- workflowId: initialize-and-verify-transaction
  summary: Create a transaction, then poll its verification result by reference.
  description: >-
    Initializes a transaction with the customer email and amount, then verifies
    the resulting reference and branches on whether the charge succeeded.
  inputs:
    type: object
    required:
    - email
    - amount
    properties:
      email:
        type: string
        description: Customer's email address the transaction is initialized for.
      amount:
        type: integer
        description: Amount in the smallest currency unit (kobo for NGN, pesewas for GHS, cents for ZAR).
      currency:
        type: string
        description: Transaction currency (NGN, GHS, ZAR or USD).
      callback_url:
        type: string
        description: Optional fully qualified callback URL to override the dashboard default.
  steps:
  - stepId: initializeTransaction
    description: >-
      Create a new transaction for the supplied customer email and amount and
      capture the authorization URL and reference Paystack returns.
    operationId: transaction_initialize
    requestBody:
      contentType: application/json
      payload:
        email: $inputs.email
        amount: $inputs.amount
        currency: $inputs.currency
        callback_url: $inputs.callback_url
    successCriteria:
    - condition: $statusCode == 201
    outputs:
      reference: $response.body#/data/reference
      authorizationUrl: $response.body#/data/authorization_url
      accessCode: $response.body#/data/access_code
  - stepId: verifyTransaction
    description: >-
      Verify the transaction using the reference returned at initialization and
      branch on whether the charge ultimately succeeded.
    operationId: transaction_verify
    parameters:
    - name: reference
      in: path
      value: $steps.initializeTransaction.outputs.reference
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      transactionStatus: $response.body#/data/status
      transactionId: $response.body#/data/id
      authorizationCode: $response.body#/data/authorization/authorization_code
    onSuccess:
    - name: paymentSucceeded
      type: end
      criteria:
      - context: $response.body
        condition: $.data.status == "success"
        type: jsonpath
    - name: paymentNotSuccessful
      type: end
      criteria:
      - context: $response.body
        condition: $.data.status != "success"
        type: jsonpath
  outputs:
    reference: $steps.initializeTransaction.outputs.reference
    authorizationUrl: $steps.initializeTransaction.outputs.authorizationUrl
    transactionStatus: $steps.verifyTransaction.outputs.transactionStatus
    authorizationCode: $steps.verifyTransaction.outputs.authorizationCode