Quaderno

Quaderno Transactions API

Unified sales transactions that both record a sale and calculate tax.

Documentation GitHub OpenAPI

Operations 1

POST /transactions.json Create a sales transaction #

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OpenAPI Specification

openapi: 3.2.0
info:
  title: Quaderno Transactions API
  description: The Quaderno API is a REST API for tax compliance, invoicing, and sales tax / VAT automation.
  version: '1.0'
  contact:
    name: Quaderno
    url: https://developers.quaderno.io
  license:
    name: Proprietary
    url: https://quaderno.io/terms/
servers:
- url: https://{account}.quadernoapp.com/api
  description: Production (account-scoped)
  variables:
    account:
      default: ACCOUNT_NAME
      description: Your Quaderno account subdomain.
security:
- basicAuth: []
tags:
- name: Transactions
  description: Unified sales transactions that both record a sale and calculate tax.
paths:
  /transactions.json:
    post:
      operationId: createTransaction
      tags:
      - Transactions
      summary: Create a sales transaction
      description: Records a sale and its tax in a single call. Quaderno determines the applicable tax from the customer's location evidence and the item tax codes, then creates the corresponding document.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/TransactionInput'
      responses:
        '201':
          description: The created transaction.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Transaction'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  schemas:
    Transaction:
      allOf:
      - $ref: '#/components/schemas/TransactionInput'
      - type: object
        properties:
          id:
            type: string
          total:
            type: number
          taxes:
            type: number
    TransactionInput:
      type: object
      required:
      - customer
      - items
      properties:
        customer:
          type: object
          description: Customer identity and location details used for tax determination.
          properties:
            first_name:
              type: string
            last_name:
              type: string
            email:
              type: string
            country:
              type: string
            postal_code:
              type: string
            region:
              type: string
            tax_id:
              type: string
        items:
          type: array
          items:
            type: object
            properties:
              description:
                type: string
              quantity:
                type: number
              unit_price:
                type: number
              tax_code:
                type: string
        payment_method:
          type: string
        evidence:
          type: object
          additionalProperties: true
    Error:
      type: object
      properties:
        error:
          type: string
        errors:
          type: object
          additionalProperties: true
  responses:
    ValidationError:
      description: The request payload failed validation.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    basicAuth:
      type: http
      scheme: basic
      description: HTTP Basic Authentication. Use your private API key as the username; the password can be any value. API keys are managed in the Quaderno account settings.