All successfully processed API requests return a JSON response with a status of 200 and a message of OK.

  "status": 200,
  "message": "OK",
  "response": "..."

If an application error is generated when processing the request, the error is reported in the status, code and message attributes of the response.

  "status": 400,
  "message": "Authentication failed",
  "code": 1200,
  "response": null

In the case of an error, the status has a value other than 200. A descriptive explanation of the error can be found in message. The code attribute identifies the category of the error.

Here's a description of error codes returned by the API.

4001200Authentication failed
4001003Request validation failure; check parameter values and types
4002102No permission to access this book
4002104No permission to access this doc
4001401Book not found
4001402Book already exists
4006001Form Type Not Found
4007002Image Group Not Found