python json删除key的所有实例，无论在树中的位置如何

问题描述

我有一些json数据，需要删除Python应用程序中某个键的每个实例。

例如，我想删除以下json数据中出现的“ badKey”。

{
  "badKey": "0001","goodKey": "5432","interestingList": [
    {
      "badKey": "0001","goodKey": "0101"
    }
  ],"coolList": {
    "nestedDeeper": [
      {
        "keepsNesting": [
          {
            "badKey": "9999","otherKey": "7890"
          }
        ],"hereToo": {
          "badKey": "foobar","goodishKey": "baz"
        }
      }
    ]
  }
}

它应该导致以下结果：

{
  "goodKey": "5432","interestingList": [
    {
      "goodKey": "0101"
    }
  ],"coolList": {
    "nestedDeeper": [
      {
        "keepsNesting": [
          {
            "otherKey": "7890"
          }
        ],"hereToo": {
          "goodishKey": "baz"
        }
      }
    ]
  }
}

有没有很好的pythonic方法来做到这一点？另外，输入和输出应为类似于以下的字节字符串（只要json可以接受，空格对我来说就没有关系）：

b'{"badKey": "0001","interestingList": [{"badKey": "0001","goodKey": "0101" }],"coolList": {"nestedDeeper": [{"keepsNesting": [{"badKey": "9999","otherKey": "7890" }],"hereToo": {"badKey": "foobar","goodishKey": "baz"}}]}}'

我确定我可以提出一些正则表达式来搜索/替换输入字符串中的数据，但我认为要确保JSON语法完整无缺，所以我想将其加载到json模块中并在那里进行操作。

解决方法

一种解决方案是递归遍历数据并删除找到的密钥：

import json


json_string = b'{"badKey": "0001","goodKey": "5432","interestingList": [{"badKey": "0001","goodKey": "0101" }],"coolList": {"nestedDeeper": [{"keepsNesting": [{"badKey": "9999","otherKey": "7890" }],"hereToo": {"badKey": "foobar","goodishKey": "baz"}}]}}'

def remove_key(d):
    if isinstance(d,dict):
        if 'badKey' in d:
            del d['badKey']
        for v in d.values():
            remove_key(v)
    elif isinstance(d,list):
        for v in d:
            remove_key(v)

data = json.loads(json_string.decode('utf-8'))
remove_key(data)
# pretty print on screen:
print(json.dumps(data,indent=4))
# ...or convert to bytes:
print(json.dumps(data).encode('utf-8'))

打印：

{
    "goodKey": "5432","interestingList": [
        {
            "goodKey": "0101"
        }
    ],"coolList": {
        "nestedDeeper": [
            {
                "keepsNesting": [
                    {
                        "otherKey": "7890"
                    }
                ],"hereToo": {
                    "goodishKey": "baz"
                }
            }
        ]
    }
}

以及字节表示形式：

b'{"goodKey": "5432","interestingList": [{"goodKey": "0101"}],"coolList": {"nestedDeeper": [{"keepsNesting": [{"otherKey": "7890"}],"hereToo": {"goodishKey": "baz"}}]}}'

,

只需通过已加载的字典进行递归：

def deleteBadKey(badKey,dictionary):
    for k,v in list(dictionary.items()):
        if k == badKey:
            del dictionary[k]
        elif isinstance(v,dict):
            deleteBadKey(badKey,v)
        elif isinstance(v,list):
            for d in v:
                deleteBadKey(badKey,d)