将嵌套的 JSON 转换为 Pandas Dataframe（以 JSON 为例）

Question

I have a JSON blob which looks like this:

    {'status': 'OK',
 'data-availability': 'available',
 'data': [{'page': 1, 'pages': 1, 'total': 7},
  [{'domain_id': '101',
    'domain_name': 'Province1',
    'domain_url': 'https://province1.com'},
   {'domain_id': '102',
    'domain_name': 'Province2',
    'domain_url': 'https://province2.com'},
   {'domain_id': '103',
    'domain_name': 'Province3',
    'domain_url': 'https://province3.com'},
   {'domain_id': '104',
    'domain_name': 'Province4',
    'domain_url': 'https://province4.com'},
   {'domain_id': '105',
    'domain_name': 'Province5',
    'domain_url': 'https://province5.com'},
   {'domain_id': '106',
    'domain_name': 'Province6',
    'domain_url': 'https://province6.com'},
   {'domain_id': '107',
    'domain_name': 'Province7',
    'domain_url': 'https://province7.com'}]]}

What I want is to normalize it into Pandas DataFrame which column are consist of domain_id, domain_name, and domain_url.

How can I accomplish this?

Answer 1

Repeated appending to a dataframe is slow . Instead, collect everything in a dictionary and then call .from_dict() :

from pandas import pd

result = defaultdict(list)
for entry in data['data'][1]:
    for key, value in entry.items():
        result[key].append(value)

print(pd.DataFrame.from_dict(result))

This outputs:

  domain_id domain_name             domain_url
0       101   Province1  https://province1.com
1       102   Province2  https://province2.com
2       103   Province3  https://province3.com
3       104   Province4  https://province4.com
4       105   Province5  https://province5.com
5       106   Province6  https://province6.com
6       107   Province7  https://province7.com

Answer 2

This does the job,

data = json.loads(test)["data"][-1]
df = pd.DataFrame()

for d in data:
  temp_df = pd.DataFrame([data[0]])
  df = pd.concat([df, temp_df])

Answer 3

You can use pd.json_normalize() .

raw_data = [{'domain_id': '101',
    'domain_name': 'Province1',
    'domain_url': 'https://province1.com'},
   {'domain_id': '102',
    'domain_name': 'Province2',
    'domain_url': 'https://province2.com'},
   {'domain_id': '103',
    'domain_name': 'Province3',
    'domain_url': 'https://province3.com'},
   {'domain_id': '104',
    'domain_name': 'Province4',
    'domain_url': 'https://province4.com'},
   {'domain_id': '105',
    'domain_name': 'Province5',
    'domain_url': 'https://province5.com'},
   {'domain_id': '106',
    'domain_name': 'Province6',
    'domain_url': 'https://province6.com'},
   {'domain_id': '107',
    'domain_name': 'Province7',
    'domain_url': 'https://province7.com'}]

# store data as df
df = pd.DataFrame({'raw':raw_data})

# split dict into columns with keys as column names
df_json = pd.json_normalize(df['raw'])

# concat dfs
df = pd.concat([df, df_json], axis=1)

# display
display(df)