Json schema中的oneOf与additionalProperties draft-04

Question

我正在尝试制作一个方案，用于验证策略语言。简而言之，一个策略与一个断言相关联。这个断言可以是运算符（and、or、not），并包含其他断言的列表。断言也可以是原语（叶子节点）。我设计了一个UML图以便更容易理解，请参考下列链接：UML diagram。

{
  "policy": {
    "name": "test",
    "expression": {
      "operator": "all",
      "value": [
        {
          "primitive": "encrypt",
          "preference": 12345,
          "usage": "required"
        },
        {
          "primitive": "sign",
          "preference": 12345,
          "usage": "required"
        }
      ],
      "preference": 12345,
      "usage": "required"
    }
  }
}

以下是我目前制作的方案：

{
  "$schema": "http://json-schema.org/draft-04/schema#",
  "type": "object",
  "minProperties": 1,
  "additionalProperties": {
    "$ref": "#/definitions/policy"
  },
  "definitions": {
    "policy": {
      "title": "Policy",
      "type": "object",
      "required": [
        "name",
        "expression"
      ],
      "additionalProperties": false,
      "properties": {
        "name": {
          "type": "string"
        },
        "expression": {
          "$ref": "#/definitions/assertion"
        }
      }
    },
    "operator": {
      "properties": {
        "value": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/assertion"
          }
        },
        "operator": {
          "enum": [
            "allOne",
            "all"
          ]
        }
      }
    },
    "primitive": {
      "properties": {
        "primitive": {
          "enum": [
            "encrypt",
            "sign"
          ]
        }
      }
    },
    "assertion": {
      "type": "object",
      "additionalProperties": false,
      "oneOf": [
        {
          "$ref": "#/definitions/operator"
        },
        {
          "$ref": "#/definitions/primitive"
        }
      ],
      "properties": {
        "preference": {
          "type": "integer",
          "minimum": 0,
          "exclusiveMinimum": true
        },
        "usage": {
          "enum": [
            "required",
            "rejected",
            "optional",
            "observed",
            "ignored"
          ]
        }
      }
    }
  }
}

我正在尝试使用“oneOf”来使用运算符或原始值的规范。但是我不确定这是否是正确的方法，因为我收到了以下错误消息：

"message" : "object instance has properties which are not allowed by the schema: [\"operator\",\"value\"]"

错误消息抱怨存在未定义的额外属性（由于"additionalProperties": false）。然而，在这些定义中已经定义了这些内容...

- freskimo

---

请查看以下链接：https://github.com/epoberezkin/ajv/blob/master/FAQ.md#additional-properties-inside-compound-keywords-anyof-oneof-etc以及https://github.com/epoberezkin/ajv/issues/134#issuecomment-242989744 - esp

好的，知道了！谢谢您的信息。 - freskimo

将第一个链接（FAQ）的更新后的URL从@esp更改为：https://ajv.js.org/faq.html#additional-properties-inside-compound-keywords-anyof-oneof-etc - peterflynn

Answer 1

oneOf、anyOf等关键字不能用于引用其他定义。它们可以在required中使用。解决方法是声明所有属性，并仅在上下文中需要时要求这些属性。我的示例将变成以下内容：

"assertion": {
  "type": "object",
  "additionalProperties": false,
  "oneOf": [
    {
      "required": [
        "operator"
      ]
    },
    {
      "required": [
        "primitive"
      ]
    }
  ],
  "properties": {
    "operator": {
      "$ref": "#/definitions/operator"
    },
    "primitive": {
      "$ref": "#/definitions/primitive"
    },
    "preference": {
      "type": "integer",
      "minimum": 0,
      "exclusiveMinimum": true
    },
    "usage": {
      "enum": [
        "required",
        "rejected",
        "optional",
        "observed",
        "ignored"
      ]
    }
  }
}

- freskimo