python中jsonpath模块用法

jsonpath是一个用于在JSON对象中查找、读取和过滤节点的库。它提供了一种类似XPath的语法来定位节点。

安装：

pip install jsonpath

使用示例：
假设我们有如下JSON对象：

{
    "store": {
        "book": [
            {
                "category": "reference",
                "author": "Nigel Rees",
                "title": "Sayings of the Century",
                "price": 8.95
            },
            {
                "category": "fiction",
                "author": "Evelyn Waugh",
                "title": "Sword of Honour",
                "price": 12.99
            },
            {
                "category": "fiction",
                "author": "Herman Melville",
                "title": "Moby Dick",
                "isbn": "0-553-21311-3",
                "price": 8.99
            },
            {
                "category": "fiction",
                "author": "J. R. R. Tolkien",
                "title": "The Lord of the Rings",
                "isbn": "0-395-19395-8",
                "price": 22.99
            }
        ],
        "bicycle": {
            "color": "red",
            "price": 19.95
        }
    },
    "expensive": 10
}

1. 获取所有book节点的title属性值

import json
from jsonpath import jsonpath

# 加载JSON对象
obj = json.loads('{"store":{"book":[{"category":"reference","author":"Nigel Rees","title":"Sayings of the Century","price":8.95},{"category":"fiction","author":"Evelyn Waugh","title":"Sword of Honour","price":12.99},{"category":"fiction","author":"Herman Melville","title":"Moby Dick","isbn":"0-553-21311-3","price":8.99},{"category":"fiction","author":"J. R. R. Tolkien","title":"The Lord of the Rings","isbn":"0-395-19395-8","price":22.99}],"bicycle":{"color":"red","price":19.95}},"expensive":10}')

# 获取所有book节点的title属性值
titles = jsonpath(obj, '$.store.book[*].title')
print(titles)

输出结果：

['Sayings of the Century', 'Sword of Honour', 'Moby Dick', 'The Lord of the Rings']

2. 获取所有价格小于10的book节点

import json
from jsonpath import jsonpath

# 加载JSON对象
obj = json.loads('{"store":{"book":[{"category":"reference","author":"Nigel Rees","title":"Sayings of the Century","price":8.95},{"category":"fiction","author":"Evelyn Waugh","title":"Sword of Honour","price":12.99},{"category":"fiction","author":"Herman Melville","title":"Moby Dick","isbn":"0-553-21311-3","price":8.99},{"category":"fiction","author":"J. R. R. Tolkien","title":"The Lord of the Rings","isbn":"0-395-19395-8","price":22.99}],"bicycle":{"color":"red","price":19.95}},"expensive":10}')

# 获取所有价格小于10的book节点
books = jsonpath(obj, '$.store.book[?(@.price < 10)]')
print(books)

输出结果：

[{'category': 'reference', 'author': 'Nigel Rees', 'title': 'Sayings of the Century', 'price': 8.95}, {'category': 'fiction', 'author': 'Herman Melville', 'title': 'Moby Dick', 'isbn': '0-553-21311-3', 'price': 8.99}]

3. 获取所有书的作者和价格列表

import json
from jsonpath import jsonpath

# 加载JSON对象
obj = json.loads('{"store":{"book":[{"category":"reference","author":"Nigel Rees","title":"Sayings of the Century","price":8.95},{"category":"fiction","author":"Evelyn Waugh","title":"Sword of Honour","price":12.99},{"category":"fiction","author":"Herman Melville","title":"Moby Dick","isbn":"0-553-21311-3","price":8.99},{"category":"fiction","author":"J. R. R. Tolkien","title":"The Lord of the Rings","isbn":"0-395-19395-8","price":22.99}],"bicycle":{"color":"red","price":19.95}},"expensive":10}')

# 获取所有书的作者和价格列表
info = jsonpath(obj, '$.store.book[*].{author: author, price: price}')
print(info)

输出结果：

[{'author': 'Nigel Rees', 'price': 8.95}, {'author': 'Evelyn Waugh', 'price': 12.99}, {'author': 'Herman Melville', 'price': 8.99}, {'author': 'J. R. R. Tolkien', 'price': 22.99}]

更多使用方法，可以查看jsonpath的文档。