json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "type": "object",
      "additionalProperties": false,
      "properties": {
          "name": {
              "type": "string"
          },
          "number": {
              "type": "integer",
              "minimum": 0
          },
          "stuff": {
              "type": "array",
              "_uniqueItems": true,
              "minItems": 1,
              "items": {
                  "type": "string"
              }
          },
          "url": {
              "type": "string",
              "format": "uri"
          }
      },
      "required": [
          "name"
      ]
  }