simple.json

{
  "schema": {
    "type": "object",
    "title": "Comment",
    "properties": {
      "name":  {
        "title": "Name",
        "type": "string"
      },
      "email":  {
        "title": "Email",
        "type": "string",
        "pattern": "^\\S+@\\S+$",
        "description": "Email will be used for evil."
      },
      "comment": {
        "title": "Comment",
        "type": "string",
        "maxLength": 20,
        "validationMessage": "Don't be greedy!"
      }
    },
    "required": ["name","email","comment"]
  },
  "form": [
    "name",
    "email",
    {
      "key": "comment",
      "type": "textarea",
      "placeholder": "Make a comment",
      "dependencies": ["name", "email"],
      "expression": "name === 'secret'",
      "disabledExpression": "email === 'test@test.com'"
    },
    {
      "type": "submit",
	  "style": "btn-info",
      "title": "OK"
    }
  ]
}