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Json-使用Python递归验证模式

jsonschema python-3.x json python

user6165050 · 技术社区 · 9 年前

我试图使用 jsonschema Python 3中的模块。

自定义JSON如下所示:

{
  "endpoint": "rfc",
  "filter_by": ["change_ref", "change_i"],
  "expression": [
    {
      "field": "first_name",
      "operator": "EQ",
      "value": "O'Neil"
    },
    "AND",
    [
      {
        "field": "last_name",
        "operator": "NEQ",
        "value": "Smith"
      },
      "OR",
      {
        "field": "middle_name",
        "operator": "EQ",
        "value": "Sam"
      }
    ]
  ],
  "limit_results_to": "2"
}

AND s和 OR

我试图验证此模式的模板位于以下代码段中:

import json
import jsonschema


def get_data(file):
    with open(file) as data_file:
        return json.load(data_file)


def json_schema_is_valid():
    data = get_data("other.json")
    valid_schema = {
        "type": "object",
        "required": ["endpoint", "filter_by", "expression", "limit_results_to"],
        "properties": {
            "endpoint": {
                "type": "string",
                "additionalProperties": False
            },
            "filter_by": {
                "type": ["string", "array"],
                "additionalProperties": False
            },
            "limit_results_to": {
                "type": "string",
                "additionalProperties": False
            },
            "expression": {
                "type": "array",
                "properties": {
                    "field": {
                        "type": "string",
                        "additionalProperties": False
                    },
                    "operator": {
                        "type": "string",
                        "additionalProperties": False
                    },
                    "value": {
                        "type": "string",
                        "additionalProperties": False
                    }
                },
                "required": ["field", "operator", "value"]
            }
        }
    }
    return jsonschema.validate(data, valid_schema)


if __name__ == '__main__':
    print(json_schema_is_valid())

现在,似乎有些问题,因为当我运行上述代码时,我得到了 None 这可能(不)是好的。当我试图修改 type property Here ,似乎未分析表达式属性。更多,我阅读 here 我可以使用我的模板递归验证我的自定义JSON模式 '$ref': '#' 但我不太懂怎么用它。有人能给我一些提示吗?

1 回复 | 直到 9 年前

Peilonrayz 9 年前

除了递归部分外,您的模式看起来正常工作。查看GitHub上的源代码 jsonschema.validate ,我们可以看到代码没有 return . 因此,我认为可以安全地假设您验证的方式是使用以下内容:

try:
    jsonschema.validate(json_data, schema)
except ...:
    print('invalid json')
else:
    print('valid json')

为了创建递归,您应该做两个定义。我在网上找到了这个方法 Recursive JSON Schema

{
    "definitions": {
        "comparison": {
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "field": {
                    "type": "string"
                },
                "operator": {
                    "type": "string"
                },
                "value": {
                    "type": "string"
                }
            },
            "required": ["field", "operator", "value"]
        }
    }
}

执行递归布尔比较有点困难。我不知道如何将数组限制为三个项,其中第二个是不同的类型,所以我选择使用一个对象,它有三个定义良好的项。此外,第一个和最后一个项目应该具有相同的类型,以便您可以像这样进行比较 (a and b) or (c and d) . 我得到了以下模式:

{
    "definitions": {
        "comparison": {
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "field": {
                    "type": "string"
                },
                "operator": {
                    "type": "string"
                },
                "value": {
                    "type": "string"
                }
            },
            "required": ["field", "operator", "value"]
        },
        "booleanComparison": {
            "type": "object",
            "additionalProperties": false,
            "properties": {
                "item1": {
                    "type": "object",
                    "oneOf": [
                        {"$ref": "#/definitions/comparison"},
                        {"$ref": "#/definitions/booleanComparison"}
                    ]
                },
                "operator": {
                    "type": "string"
                },
                "item2": {
                    "type": "object",
                    "oneOf": [
                        {"$ref": "#/definitions/comparison"},
                        {"$ref": "#/definitions/booleanComparison"}
                    ]
                }
            },
            "required": ["item1", "operator", "item2"]
        }
    },
    "type": "object",
    "properties": {
        "endpoint": {
            "type": "string"
        },
        "filter_by": {
            "type": ["string", "array"]
        },
        "limit_results_to": {
            "type": "string",
            "additionalProperties": false
        },
        "expression": {
            "type": "object",
            "oneOf": [
                {"$ref": "#/definitions/comparison"},
                {"$ref": "#/definitions/booleanComparison"}
            ]
        }
    },
    "required": ["endpoint", "filter_by", "expression", "limit_results_to"]
}

{
    "endpoint": "rfc",
    "filter_by": ["change_ref", "change_i"],
    "limit_results_to": "2",
    "expression": {
        "item1": {
            "field": "first_name",
            "operator": "EQ",
            "value": "O'Neil"
        },
        "operator": "AND",
        "item2": {
            "item1": {
                "field": "last_name",
                "operator": "NEQ",
                "value": "Smith"
            },
            "operator": "OR",
            "item2": {
                "field": "middle_name",
                "operator": "EQ",
                "value": "Sam"
            }
        }
    }
}

但是说如果你改变它是无效的 "value": "Sam" 到 "value": true