解析多层JSON Python

Question

JSON响应-

{
  "001": {
    "STUDENTTYPE": {
      "TYPE": "Boarder"
    },
    "ACADEMICS": [
      {
        "SCI": 42,
        "MTH": 22
      },
      {
        "SCI": 49,
        "MTH": 36
      },
      {
        "SCI": 42,
        "MTH": 26
      }
    ],
    "ROLL": "001",
    "NAME": "Ben",
    "CLASS": "XI",
    "CLASSTEACHER": "Aka",
    "HOME": "Katrasgarh"
  },
  "002": {
    "STUDENTTYPE": {
      "TYPE": "DayScholar"
    },
    "ACADEMICS": [
      {
        "SCI": 43,
        "MTH": 24
      },
      {
        "SCI": 43,
        "MTH": 36
      },
      {
        "SCI": 47,
        "MTH": 28
      }
    ],
    "ROLL": "002",
    "NAME": "Bee",
    "CLASS": "XI",
    "CLASSTEACHER": "Ama",
    "HOME": "Kats"
  }
  ....
}

我无法获取内部json。这是我到现在为止所做的-

jsonLocation = sys.argv[1]
jsonFile = open(jsonLocation, 'rb')
jsonData = json.load(jsonFile)

for rollNo in jsonData:
print(rollNo)
for studentItems in jsonData[rollNo]:
     print(studentItems['ROLL'])
     print(studentItems['NAME'])
     print(studentItems['CLASS'])
     print(studentItems['CLASSTEATCHER'])
     print(studentItems['HOME'])
     print(studentItems['STUDENTTYPETYPE']['TYPE'])

我确实得到了studentItems中每个键的值，但在我看来这是一种笨拙的方法。我也尝试过json.dump，但是失败了，错误是JSON是不可序列化的。 有没有更好的方法来迭代这个JSON格式？你知道吗

这是我要找的样本输出-

001:

001
Ben
XI
Aka
Katrasgarh

Boarder

42,22
49,36
42,26

002:

002
Bee
XI
Ama
Kats
..
.

Answer 1

关于您希望输出的外观有点不清楚，但我继续，只是将嵌套的json展平，然后将其重建为数据帧。从那里，您可以通过切片/过滤表、写入csv或执行任何您想执行的操作来访问数据。但实际上，每一行都代表ROLL，带有属性，以及相应的科学和数学分数，索引号从0开始。如果一些学生在ACADEMICS键中有一个较长的列表，那么对于考试分数最低的学生，您将有一个带有null的行。你知道吗

给定：

jsonData = {
  "001": {
    "STUDENTTYPE": {
      "TYPE": "Boarder"
    },
    "ACADEMICS": [
      {
        "SCI": 42,
        "MTH": 22
      },
      {
        "SCI": 49,
        "MTH": 36
      },
      {
        "SCI": 42,
        "MTH": 26
      }
    ],
    "ROLL": "001",
    "NAME": "Ben",
    "CLASS": "XI",
    "CLASSTEACHER": "Aka",
    "HOME": "Katrasgarh"
  },
  "002": {
    "STUDENTTYPE": {
      "TYPE": "DayScholar"
    },
    "ACADEMICS": [
      {
        "SCI": 43,
        "MTH": 24
      },
      {
        "SCI": 43,
        "MTH": 36
      },
      {
        "SCI": 47,
        "MTH": 28
      }
    ],
    "ROLL": "002",
    "NAME": "Bee",
    "CLASS": "XI",
    "CLASSTEACHER": "Ama",
    "HOME": "Kats"
  }

}

代码：

import json
import pandas as pd
import re

def flatten_json(y):
    out = {}
    def flatten(x, name=''):
        if type(x) is dict:
            for a in x:
                flatten(x[a], name + a + '_')
        elif type(x) is list:
            i = 0
            for a in x:
                flatten(a, name + str(i) + '_')
                i += 1
        else:
            out[name[:-1]] = x
    flatten(y)
    return out


flat = flatten_json(jsonData)



results = pd.DataFrame()
columns_list = list(flat.keys())
for item in columns_list:
    row_idx = re.findall(r'(\d+)\_', item )[0]
    column = item.replace(row_idx + '_', '')
    row_idx = int(row_idx)
    value = flat[item]

    results.loc[row_idx, column] = value

输出：

print (results.to_string())
  STUDENTTYPE_TYPE  ACADEMICS_0_SCI  ACADEMICS_0_MTH  ACADEMICS_1_SCI  ACADEMICS_1_MTH  ACADEMICS_2_SCI  ACADEMICS_2_MTH ROLL NAME CLASS CLASSTEACHER        HOME
1          Boarder             42.0             22.0             49.0             36.0             42.0             26.0  001  Ben    XI          Aka  Katrasgarh
2       DayScholar             43.0             24.0             43.0             36.0             47.0             28.0  002  Bee    XI          Ama        Kats