Juspay Transactions API

openapi: 3.2.0
info:
  title: Juspay Express Checkout Transactions API
  description: Server-to-server REST API for the Juspay payments orchestration and checkout platform.
  version: '1.0'
  contact:
    name: Juspay
    url: https://juspay.io/in
servers:
- url: https://api.juspay.in
  description: Production
- url: https://sandbox.juspay.in
  description: Sandbox
security:
- basicAuth: []
tags:
- name: Transactions
  description: Server-to-server transaction processing against an order.
paths:
  /txns:
    post:
      operationId: createTransaction
      tags:
      - Transactions
      summary: Create a transaction
      description: Server-to-server transaction endpoint that processes a payment against an existing order with a chosen payment method (card, UPI, netbanking, wallet). Documented as exempt from the standard order authentication flow. Body fields below are modeled from the documented flow and are not exhaustive.
      parameters:
      - $ref: '#/components/parameters/MerchantId'
      - $ref: '#/components/parameters/RoutingId'
      requestBody:
        required: true
        content:
          application/x-www-form-urlencoded:
            schema:
              $ref: '#/components/schemas/TransactionInput'
      responses:
        '200':
          description: Transaction result / next action.
          content:
            application/json:
              schema:
                type: object
                additionalProperties: true
        '401':
          $ref: '#/components/responses/Unauthorized'
components:
  responses:
    Unauthorized:
      description: Missing or invalid credentials.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  schemas:
    TransactionInput:
      type: object
      required:
      - order_id
      - payment_method_type
      properties:
        order_id:
          type: string
        payment_method_type:
          type: string
          description: e.g. CARD, UPI, NB (netbanking), WALLET.
        payment_method:
          type: string
        redirect_after_payment:
          type: boolean
        format:
          type: string
          description: Response format, e.g. json.
    Error:
      type: object
      properties:
        status:
          type: string
        error_code:
          type: string
        error_message:
          type: string
  parameters:
    RoutingId:
      name: x-routing-id
      in: header
      required: false
      description: Routing key that pins the payment session lifecycle - typically the customer_id, or an order/cart id for guest checkout.
      schema:
        type: string
    MerchantId:
      name: x-merchantid
      in: header
      required: true
      description: Merchant ID issued by Juspay.
      schema:
        type: string
  securitySchemes:
    basicAuth:
      type: http
      scheme: basic
      description: 'HTTP Basic authentication. The API key is the username and the password is an empty string; the pair is Base64-encoded into `Authorization: Basic <credentials>`. An `x-merchantid` header is also required on requests.'