Which REST operation (GET, PUT, or POST) for validating information?

Question

My users enter a few information fields in an iOS app. This information must be validated on my server, which has a RESTful API. After validation the UI of the iOS app chang

Answer 1

I recommend using a ValidationResource and two requests. Each instance of this resource represents the validation of a set of data. The workflow:

1. Create new ValidationResource

• Request: POST /path/to/validations
  • data to validate as the body
• Response: 201 Created
  • Location: /path/to/validations/

2. Look up result

• Request: GET /path/to/validations/
• Respons: 200 OK
  • body: {'valid': true} or {'valid': false}

This is a RESTful approach in which the Validation is a Resource with server state.