Interswitch Web Checkout And Confirm

arazzo: 1.0.1
info:
  title: Interswitch Web Checkout And Confirm
  summary: Initiate a hosted Web Redirect payment, then server-side requery to confirm before delivering value.
  description: >-
    Implements the mandatory Web Checkout (Webpay) two-phase pattern. The
    workflow posts the checkout form to redirect the customer to the hosted
    payment page, then performs the authoritative server-side requery against the
    gettransaction endpoint. It branches on the documented success code (00):
    only an approved status with a matching amount should release value. The form
    is sent as application/x-www-form-urlencoded per the spec.
  version: 1.0.0
sourceDescriptions:
- name: checkoutApi
  url: ../openapi/interswitch-checkout-api-openapi.yml
  type: openapi
- name: transactionsApi
  url: ../openapi/interswitch-transactions-api-openapi.yml
  type: openapi
workflows:
- workflowId: checkout-and-confirm
  summary: Initiate a hosted payment and confirm it server-side before delivering value.
  description: >-
    Posts the checkout form to start a hosted payment, then requeries the
    transaction status and branches on the approved (00) response code.
  inputs:
    type: object
    required:
    - accessToken
    - merchantCode
    - payItemId
    - txnRef
    - amount
    - currency
    - custEmail
    - siteRedirectUrl
    properties:
      accessToken:
        type: string
        description: Bearer access token from the Passport OAuth token endpoint.
      merchantCode:
        type: string
        description: Merchant code issued by Interswitch.
      payItemId:
        type: string
        description: Pay item identifier configured on the merchant account.
      txnRef:
        type: string
        description: Unique merchant transaction reference.
      amount:
        type: integer
        description: Amount in minor currency units (kobo).
      currency:
        type: string
        description: ISO 4217 numeric currency code (e.g. 566 for NGN).
      custEmail:
        type: string
        description: Customer email address.
      siteRedirectUrl:
        type: string
        description: URL the hosted page redirects back to after payment.
  steps:
  - stepId: initiatePayment
    description: >-
      Post the checkout form to redirect the customer to the Interswitch hosted
      payment page. A 302 redirect is the documented success response.
    operationId: initiateWebRedirectPayment
    parameters:
    - name: Authorization
      in: header
      value: Bearer $inputs.accessToken
    requestBody:
      contentType: application/x-www-form-urlencoded
      payload:
        merchant_code: $inputs.merchantCode
        pay_item_id: $inputs.payItemId
        txn_ref: $inputs.txnRef
        amount: $inputs.amount
        currency: $inputs.currency
        cust_email: $inputs.custEmail
        site_redirect_url: $inputs.siteRedirectUrl
    successCriteria:
    - condition: $statusCode == 302
  - stepId: confirmTransaction
    description: >-
      Authoritative server-side requery. Branches on ResponseCode: 00 means the
      transaction is approved and value may be released.
    operationId: getTransactionStatus
    parameters:
    - name: Authorization
      in: header
      value: Bearer $inputs.accessToken
    - name: merchantcode
      in: query
      value: $inputs.merchantCode
    - name: transactionreference
      in: query
      value: $inputs.txnRef
    - name: amount
      in: query
      value: $inputs.amount
    successCriteria:
    - condition: $statusCode == 200
    outputs:
      responseCode: $response.body#/ResponseCode
      settledAmount: $response.body#/Amount
      paymentReference: $response.body#/PaymentReference
    onSuccess:
    - name: approved
      type: end
      criteria:
      - context: $response.body
        condition: $.ResponseCode == "00"
        type: jsonpath
  outputs:
    responseCode: $steps.confirmTransaction.outputs.responseCode
    settledAmount: $steps.confirmTransaction.outputs.settledAmount
    paymentReference: $steps.confirmTransaction.outputs.paymentReference