验证嵌套字典的值类型

Question

我查看了marshmallow中的python数据，food字段是一个list，list里面存放的是dict。我只能做到这一步。事实上，我想验证dict中的值是int而不是string。我应该如何修改我的代码？

from marshmallow import Schema, fields, pprint

class UserSchema(Schema):
    name = fields.Str()
    food = fields.List(fields.Dict)

user_data = {
    "name": "Ken",
    "food": [{'apple': 2, 'banana': 4}, {'apple': '2', 'banana': '4'}]
}

result = UserSchema().load(user_data)
pprint(result)

Answer 1

下面的代码应该可以验证您的数据模式。
看代码中的cmets，很简单的解释。

from marshmallow import ValidationError, Schema, fields, pprint # Added `ValidationError`.

user_data = {
    "name": "Ken",
    "food": [
        {'apple': 2, 'banana': 4}, 
        {'apple': '2', 'banana': '4'}
    ]
} # `user_data` is as is without changes.

# New function for validation your dictionary.
def validate_value_type(dict):
    for key in dict:
        if type(dict[key]) is not int:
            raise ValidationError(f'Type of {key}\'s value is not Integer')

# `UserSchema` class with changes.
class UserSchema(Schema):
    name = fields.Str()
    food = fields.List(fields.Dict(validate=validate_value_type)) # Added validation function.

# Wrapped `load` in `try/catch`.
try:
    UserSchema().load(user_data)
except ValidationError as err:
    pprint(err.messages)

以上代码输出：

{'food': {1: ["Type of apple's value is not Integer"]}}

Answer 2

尝试像这样遍历并检查每个值类型

DictList = [{'apple': 2, 'banana': 4}, {'apple': '2', 'banana': '4'}]

user_data = {
    "name": "Ken",
    "food": DictList
}



def verify():
    for i in DictList:
        for k in i:
            if type(i[k]) == int:
                return True
            return False




if verify():
    result = UserSchema().load(user_data)
    pprint(result)

Answer 3

在您的函数中检查此代码：

print(type(var_name))