jsonpath
用于处理爬虫爬取的json结构化数据

from jsonpath import jsonpath
import requests
import jsonpath
import json

# 获取拉勾网城市json字符串
url = 'http://www.lagou.com/lbs/getAllCitySearchLabels.json'
headers = {"User-Agent": "Mozilla/5.0 (compatible; MSIE 9.0; Windows NT 6.1; Trident/5.0)"}
response =requests.get(url, headers=headers)
html_str = response.content.decode()

# 把json格式字符串转换成python对象
jsonobj = json.loads(html_str)

# 从根节点开始，获取所有key为name的值
citylist = jsonpath.jsonpath(jsonobj,'$..name')

# 写入文件
with open('city_name.txt','w') as f:
    content = json.dumps(citylist, ensure_ascii=False)
    f.write(content)




转载于:https://www.cnblogs.com/0916m/p/11484357.html

JSONPath和XPath对照
参考下 https://www.cnblogs.com/youring2/p/10942728.html




XPath
JSONPath




/store/book/author
$.store.book[*].author


//author
$…author


/store/*
$.store.*


/store//price
$.store…price


//book[3]
$…book[2]


//book[last()]
$…book[(@.length-1)]   或者   $…book[-1:]


//book[position()< 3]
$…book[0,1] 或者 $…book[:2]


//book[isbn]
$…book[?(@.isbn)]


//book[price<10]
$…book[?(@.price<10)]


//*
$…*


{ “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

}

}

}

class下载

 <?php
/*
*JsonPath的具体使用帮助
*http://goessner.net/articles/JsonPath/
*
*/


require_once __DIR__.'/Peekmo/JsonPath/JsonStore.php';
require_once __DIR__.'/Peekmo/JsonPath/JsonPath.php';
use Peekmo\JsonPath\JsonStore;

 $json = '{
            "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,
                        "code": "01.02"
                    },
                    {
                        "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
                }
            }
        }';
        $store = new JsonStore($json);

    // Returns an array with all categories from books which have an isbn attribute
   $res = $store->get("$..book[?(@.isbn)].category");
   $res1 = $store->get("$..book");
   $res2=$store->get('$.store.book[*]');
  
    //$res = $store->get("$..book[?(@.isbn)].category", true); // You can set true to get only unique results
    var_dump($res2[0]['title']);  





XPath

JSONPath

Result

/store/book/author

$.store.book[*].author

the authors of all books in the store

//author

$..author

all authors

/store/*

$.store.*

all things in store, which are some books and a red bicycle.

/store//price

$.store..price

the price of everything in the store.

//book[3]

$..book[2]

the third book

//book[last()]

$..book[(@.length-1)]
$..book[-1:]

the last book in order.

//book[position()<3]

$..book[0,1]
$..book[:2]

the first two books

//book[isbn]

$..book[?(@.isbn)]

filter all books with isbn number

//book[price<10]

$..book[?(@.price<10)]

filter all books cheapier than 10

//*

$..*

all Elements in XML document. All members of JSON structure.


参考

一、概念


jsonpath  解析多层嵌套json数据。信息抽取类库，从JSON文档中抽取指定信息的工具。


二、安装&使用

当遇到层级比较深的字典时，用jsonpath取值比较方便。 

pip install jsonpath

import jsonpath
res = jsonpath.jsonpath(dic_name,'$..key_name')

三、使用场景

1、接口自动化测试时，取接口返回值response的具体字段，用作断言 

四、jsonpath与XML语法对比

Xpath
			
JSONPath
			
描述
		
/
			
$
			
根节点
		
.
			
@
			
现行节点
		
/
			
. or []
			
取子节点
		
..
			
n/a
			
取父节点，Jsonpath未支持
		
//
			
..
			
不管位置，选择所有符合条件的节点
		
*
			
*
			
匹配所有元素节点
		
@
			
n/a
			
根据属性访问，JsonPath不支持
		
[]
			
[]
			
迭代器（可以在里边做简单的迭代操作，如数组下标，根据内容选值等）
		
|
			
[,]
			
支持迭代器中做多选
		
[]
			
?()
			
支持过滤操作
		
n/a
			
()
			
支持表达式计算
		
()
			
n/a
			
分组，JsonPath不支持
		
参考:

https://www.cnblogs.com/denise1108/p/10265911.html