我正在将JSON读入我的脚本并构建一个由字典组成的列表。
我的JSON:
{
"JMF": {
"table1": {
"email": "JMF1@fake.com",
"guests": [
"test1",
"test2"
]
},
"table2": {
"email": "JMF2@fake.com",
"guests": [
"test3"
]
}
},
"JMC": {
"table3": {
"email": "JMC1@fake.com",
"guests": [
"test11"
]
}
},
"JMD": {
"table4": {
"email": "JMD1@fake.com",
"guests": [
"test12"
]
},
"table5": {
"email": "JMD2@fake.com",
"guests": [
"test17"
]
}
}
}
我的代码:
def get_json():
userinfo_list = []
with open('guest_users.json') as json_file:
json_file = json.load(json_file)
keys = json_file.keys()
for key in keys:
userinfo = {}
for table_key in json_file[key].keys():
email = json_file[key][table_key]['email']
users_dict = {}
users_list = []
for user in json_file[key][table_key]['guests']:
users_dict['username'] = user
users_dict['password'] = generate_password()
users_list.append(users_dict)
userinfo['company'] = key
userinfo['email'] = email
userinfo['userinfo'] = users_list
userinfo_list.append(userinfo)
print(userinfo)
print(userinfo_list)
问题是,只要我的JSON有两个子键(userinfo_list
),table*
中的值就会被覆盖。
这是我得到的输出,没有意义:
{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}
[{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}]
{'userinfo': [{'username': 'test17', 'password': 'A8Jue5'}], 'email': 'JMD2@fake.com', 'company': 'JMD'}
[{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}, {'userinfo': [{'username': 'test17', 'password': 'A8Jue5'}], 'email': 'JMD2@fake.com', 'company': 'JMD'}]
{'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}
[{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}]
{'userinfo': [{'username': 'test2', 'password': 'GagQ59'}, {'username': 'test2', 'password': 'GagQ59'}], 'email': 'JMF1@fake.com', 'company': 'JMF'}
[{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}, {'userinfo': [{'username': 'test2', 'password': 'GagQ59'}, {'username': 'test2', 'password': 'GagQ59'}], 'email': 'JMF1@fake.com', 'company': 'JMF'}]
{'userinfo': [{'username': 'test3', 'password': 'U9gP0j'}], 'email': 'JMF2@fake.com', 'company': 'JMF'}
[{'userinfo': [{'username': 'test11', 'password': '1fEAg0'}], 'email': 'JMC1@fake.com', 'company': 'JMC'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}, {'userinfo': [{'username': 'test12', 'password': '0JSpc0'}], 'email': 'JMD1@fake.com', 'company': 'JMD'}, {'userinfo': [{'username': 'test3', 'password': 'U9gP0j'}], 'email': 'JMF2@fake.com', 'company': 'JMF'}, {'userinfo': [{'username': 'test3', 'password': 'U9gP0j'}], 'email': 'JMF2@fake.com', 'company': 'JMF'}]
答案 0 :(得分:3)
您将在每次迭代时重新附加相同的单个词典:
users_dict = {} # only one copy of this dictionary is ever created
users_list = []
for user in json_file[key][table_key]['guests']:
users_dict['username'] = user
users_dict['password'] = generate_password()
users_list.append(users_dict) # appending a reference to users_dict
追加不创建副本,因此您可以获得对同一字典的多个引用,并且您只会看到反映的最后一个更改。您使用userinfo
字典犯了同样的错误。
在循环中创建一个新词典:
users_list = []
for user in json_file[key][table_key]['guests']:
users_dict = {}
users_dict['username'] = user
users_dict['password'] = generate_password()
users_list.append(users_dict)
您可以在创建字典时直接指定键值对:
users_list = []
for user in json_file[key][table_key]['guests']:
users_dict = {
'username': user,
'password': generate_password()
}
users_list.append(users_dict)
这可以通过list comprehension简化为:
users_list = [{'username': user, 'password': generate_password()}
for user in json_file[key][table_key]['guests']]
请注意,您无需调用dict.keys()
来循环字典。您可以使用完全相同的结果直接在上循环。您可能希望循环遍历.items()
并避免每次都要查找密钥的值,并在您根本不需要密钥时使用.values()
:
userinfo_list = []
for company, db in json_file.items():
for table in db.values():
userinfo = {
'company': company,
'email': table['email'],
'userinfo': [
{'username': user, 'password': generate_password()}
for user in table['guests']]
}
userinfo_list.append(userinfo)
每个公司每个表格的字典创建也可以用列表理解来代替,但是此时坚持使用嵌套的for
循环可能会更容易理解未来的读者。
以上现在产生:
[{'company': 'JMF',
'email': 'JMF1@fake.com',
'userinfo': [{'password': 'random_password_really', 'username': 'test1'},
{'password': 'random_password_really', 'username': 'test2'}]},
{'company': 'JMF',
'email': 'JMF2@fake.com',
'userinfo': [{'password': 'random_password_really', 'username': 'test3'}]},
{'company': 'JMC',
'email': 'JMC1@fake.com',
'userinfo': [{'password': 'random_password_really', 'username': 'test11'}]},
{'company': 'JMD',
'email': 'JMD1@fake.com',
'userinfo': [{'password': 'random_password_really', 'username': 'test12'}]},
{'company': 'JMD',
'email': 'JMD2@fake.com',
'userinfo': [{'password': 'random_password_really', 'username': 'test17'}]}]
来自您的示例数据(以及我自己对generate_password()
的定义)。