json - JSON Schema 中的 "required"与 "optional"有什么区别

Question

有时，我注意到以下 JSON 架构:

{
    "type": "object",   
    "properties": {
        "address": {
                   "type": "string",
                   "required": true
            }
     }

}

对

{
    "type": "object",   
    "properties": {
        "address": {
                   "type": "string",
                   "optional": false
            }
     }

}

那么上面例子中的required和optional有什么区别呢？

Answer 1

IETF draft v4 JSON 模式的只定义required，不包含optional。

引用 section关于草稿 v4 中的 必需:

Valid values: The value of this keyword MUST be an array. This array MUST have at least one element. Elements of this array MUST be strings, and MUST be unique.

Conditions for successful validation: An object instance is valid against this keyword if its property set contains all elements in this keyword's array value.

实际上，使用 required 使得所有属性都是可选的该名称不包含在给定的字符串数组中。