BillingEngine

BillingEngine Customers API

Customers of the account.

GitHub OpenAPI

Operations 4

GET /customers List customers #
POST /customers Create a customer #
GET /customers/{id} Get a customer #
PATCH /customers/{id} Change a customer #

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/openapi/billingengine-customers-api-openapi.yml

Schemas & Data

📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-invoice-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-invoice-input-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-invoice-detail-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-customer-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-payment-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/json-schema/billingengine-payment-input-schema.json

Other Resources

🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/billingengine/refs/heads/main/apis.yml

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OpenAPI Specification

billingengine-customers-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: BillingEngine Customers API
  version: 1.0.0
  summary: REST API for customers, invoices and payments of BillingEngine.
  description: 'BillingEngine is online invoicing software for freelancers and small businesses in Germany. Every invoice is an e-invoice (ZUGFeRD and XRechnung, EN 16931).


    The API is available in the paid plans. Authenticate with the API key from your settings as a bearer token. All requests and responses use JSON; amounts are given in the currency of the record, dates as YYYY-MM-DD. Each key may send 60 requests per minute. New invoices are created as drafts and count towards the monthly invoice maximum of the plan.


    Documentation: https://www.billingengine.com/en/api'
  termsOfService: https://www.billingengine.com/en/terms_of_service
  contact:
    name: BillingEngine
    url: https://www.billingengine.com/en/contact
  license:
    name: Proprietary
    url: https://www.billingengine.com/en/terms_of_service
servers:
- url: https://www.billingengine.com/api/v1
  description: Production
security:
- bearerAuth: []
tags:
- name: Customers
  description: Customers of the account.
paths:
  /customers:
    get:
      tags:
      - Customers
      operationId: listCustomers
      summary: List customers
      description: All customers, ordered. The query parameter searches company, names and email.
      parameters:
      - name: query
        in: query
        schema:
          type: string
        description: Search company, names and email.
      - name: page
        in: query
        schema:
          type: integer
          minimum: 1
          default: 1
        description: Page number.
      - name: per_page
        in: query
        schema:
          type: integer
          minimum: 1
          maximum: 100
          default: 25
        description: Records per page, at most 100.
      responses:
        '200':
          description: A page of customers.
          content:
            application/json:
              schema:
                type: object
                required:
                - data
                - pagination
                properties:
                  data:
                    type: array
                    items:
                      $ref: '#/components/schemas/Customer'
                  pagination:
                    $ref: '#/components/schemas/Pagination'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
    post:
      tags:
      - Customers
      operationId: createCustomer
      summary: Create a customer
      description: A new customer needs a company or a last name and an address with line 1, postal code, city and country. The number is assigned automatically.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CustomerInput'
      responses:
        '201':
          description: The created customer.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Customer'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '422':
          $ref: '#/components/responses/Unprocessable'
  /customers/{id}:
    parameters:
    - name: id
      in: path
      required: true
      schema:
        type: integer
      description: Record id.
    get:
      tags:
      - Customers
      operationId: getCustomer
      summary: Get a customer
      responses:
        '200':
          description: The customer.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Customer'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          $ref: '#/components/responses/NotFound'
    patch:
      tags:
      - Customers
      operationId: updateCustomer
      summary: Change a customer
      description: PUT is accepted as well.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CustomerInput'
      responses:
        '200':
          description: The changed customer.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Customer'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          $ref: '#/components/responses/NotFound'
        '422':
          $ref: '#/components/responses/Unprocessable'
components:
  responses:
    Unprocessable:
      description: The record is invalid. The messages explain why.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Errors'
    Unauthorized:
      description: Missing or invalid API key.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Errors'
    BadRequest:
      description: 'Malformed request: missing parameter, invalid JSON, invalid date or invalid filter.'
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Errors'
    NotFound:
      description: Record not found.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Errors'
    Forbidden:
      description: The API is not available in the Free plan, or the monthly invoice maximum of the plan has been reached.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Errors'
  schemas:
    CustomerInput:
      type: object
      properties:
        company:
          type: string
        first_name:
          type: string
        last_name:
          type: string
        email:
          type: string
          format: email
        phone:
          type: string
        vat_number:
          type: string
        buyer_reference:
          type: string
        address_attributes:
          $ref: '#/components/schemas/Address'
    Customer:
      type: object
      properties:
        id:
          type: integer
        number:
          type:
          - string
          - integer
          - 'null'
        name:
          type: string
          description: Company, or first and last name.
        company:
          type:
          - string
          - 'null'
        first_name:
          type:
          - string
          - 'null'
        last_name:
          type:
          - string
          - 'null'
        email:
          type:
          - string
          - 'null'
        phone:
          type:
          - string
          - 'null'
        vat_number:
          type:
          - string
          - 'null'
        buyer_reference:
          type:
          - string
          - 'null'
          description: Buyer reference (BT-10), for example a Leitweg-ID.
        address:
          oneOf:
          - $ref: '#/components/schemas/Address'
          - type: 'null'
    Address:
      type: object
      properties:
        line_1:
          type: string
        line_2:
          type:
          - string
          - 'null'
        postal_code:
          type: string
        city:
          type: string
        region:
          type:
          - string
          - 'null'
        country:
          type: string
          description: ISO country code such as DE.
          examples:
          - DE
    Errors:
      type: object
      required:
      - errors
      properties:
        errors:
          type: array
          items:
            type: string
    Pagination:
      type: object
      required:
      - page
      - per_page
      - pages
      - count
      properties:
        page:
          type: integer
        per_page:
          type: integer
        pages:
          type: integer
        count:
          type: integer
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'The API key from the settings of your account, sent as "Authorization: Bearer <key>". Only available in the paid plans.'
externalDocs:
  description: API documentation
  url: https://www.billingengine.com/en/api