Submit a response to a form

{
  "type": "object",
  "properties": {
    "contribution": {
      "type": "string"
    },
    "date": {
      "type": "string",
      "format": "date-time"
    },
    "form": {
      "type": "string"
    },
    "id": {
      "type": "string"
    },
    "responses": {
      "type": "object"
    },
    "user": {
      "type": "string"
    }
  }
}