python - 值错误 : Expected object or value when reading json as pandas dataframe

Question

示例数据:

{
   "_id": "OzE5vaa3p7",
   "categories": [
      {
         "__type": "Pointer",
         "className": "Category",
         "objectId": "nebCwWd2Fr"
      }
   ],
   "isActive": true,
   "imageUrl": "https://firebasestorage.googleapis.com/v0/b/shopgro-1376.appspot.com/o/Barcode%20Data%20Upload%28II%29%2FAnil_puttu_flour_500g.png?alt=media&token=9cf63197-0925-4360-a31a-4675f4f46ae2",
   "barcode": "8908001921015",
   "isFmcg": true,
   "itemName": "Anil puttu flour 500g",
   "mrp": 58,
   "_created_at": "2016-10-02T13:49:03.281Z",
   "_updated_at": "2017-02-22T08:48:09.548Z"
}

{
   "_id": "ENPCL8ph1p",
   "categories": [
      {
         "__type": "Pointer",
         "className": "Category",
         "objectId": "B4nZeUHmVK"
      }
   ],
   "isActive": true,
   "imageUrl": "https://firebasestorage.googleapis.com/v0/b/kirananearby-9eaa8.appspot.com/o/Barcode%20data%20upload%2FYippee_Magic_Masala_Noodles,_70_g.png?alt=media&token=d9e47bd7-f847-4d6f-9460-4be8dbcaae00",
   "barcode": "8901725181222",
   "isFmcg": true,
   "itemName": "Yippee Magic Masala Noodles, 70 G",
   "mrp": 12,
   "_created_at": "2016-10-02T13:49:03.284Z",
   "_updated_at": "2017-02-22T08:48:09.074Z"
}

我试过:

import pandas as pd
data= pd.read_json('Data.json')

getting error ValueError: Expected object or value

还有

import json
with open('gdb.json') as datafile:
    data = json.load(datafile)
retail = pd.DataFrame(data)

error: json.decoder.JSONDecodeError: Extra data: line 2 column 1 (char 509)

with open('gdb.json') as datafile:
for line in datafile:
    data = json.loads(line)
retail = pd.DataFrame(data)

error: json.decoder.JSONDecodeError: Extra data: line 1 column 577 (char 576)

如何将这个json读入pandas

Answer 1

您的 JSON 格式不正确。

ValueError: Expected object or value 如果您输入错误的文件名，可能会发生。 Data.json 是否存在？我注意到您在其他尝试中使用了 gdb.json。

确认文件名正确后，您必须修复 JSON。您现在拥有的是由空格分隔的两条断开连接的记录。 JSON 中的列表必须是方括号内的有效数组，并用逗号分隔:[{record1}, {record2}, ...]

此外，对于 pandas，您应该将数组放在名为 "data" 的根元素下:

{ "data": [ {record1}, {record2}, ... ] }

您的 JSON 最终应如下所示:

{"data":
    [{
        "_id": "OzE5vaa3p7",
        "categories": [
            {
                "__type": "Pointer",
                "className": "Category",
                "objectId": "nebCwWd2Fr"
            }
        ],
        "isActive": true,
        "imageUrl": "https://firebasestorage.googleapis.com/v0/b/shopgro-1376.appspot.com/o/Barcode%20Data%20Upload%28II%29%2FAnil_puttu_flour_500g.png?alt=media&token=9cf63197-0925-4360-a31a-4675f4f46ae2",
        "barcode": "8908001921015",
        "isFmcg": true,
        "itemName": "Anil puttu flour 500g",
        "mrp": 58,
        "_created_at": "2016-10-02T13:49:03.281Z",
        "_updated_at": "2017-02-22T08:48:09.548Z"
    }
    ,
    {
        "_id": "ENPCL8ph1p",
        "categories": [
            {
                "__type": "Pointer",
                "className": "Category",
                "objectId": "B4nZeUHmVK"
            }
        ],
        "isActive": true,
        "imageUrl": "https://firebasestorage.googleapis.com/v0/b/kirananearby-9eaa8.appspot.com/o/Barcode%20data%20upload%2FYippee_Magic_Masala_Noodles,_70_g.png?alt=media&token=d9e47bd7-f847-4d6f-9460-4be8dbcaae00",
        "barcode": "8901725181222",
        "isFmcg": true,
        "itemName": "Yippee Magic Masala Noodles, 70 G",
        "mrp": 12,
        "_created_at": "2016-10-02T13:49:03.284Z",
        "_updated_at": "2017-02-22T08:48:09.074Z"
    }]}

最后，pandas 调用这种格式split orientation，所以你必须按如下方式加载它:

df = pd.read_json('gdb.json', orient='split')

df 现在包含以下数据框:

          _id                                                   categories  isActive                                                     imageUrl        barcode  isFmcg                           itemName  mrp                      _created_at                      _updated_at
0  OzE5vaa3p7  [{'__type': 'Pointer', 'className': 'Category', 'objectI...      True  https://firebasestorage.googleapis.com/v0/b/shopgro-1376...  8908001921015    True              Anil puttu flour 500g   58 2016-10-02 13:49:03.281000+00:00 2017-02-22 08:48:09.548000+00:00
1  ENPCL8ph1p  [{'__type': 'Pointer', 'className': 'Category', 'objectI...      True  https://firebasestorage.googleapis.com/v0/b/kirananearby...  8901725181222    True  Yippee Magic Masala Noodles, 70 G   12 2016-10-02 13:49:03.284000+00:00 2017-02-22 08:48:09.074000+00:00