In the pydantic v1 there was an option to add kwargs which would get passed to json.dumps via **dumps_kwargs. However, in pydantic v2 if you try to add extra kwargs to BaseModel.json() it fails with the error TypeError: `dumps_kwargs` keyword arguments are no longer supported.

在pydtic v1中，有一个添加kwargs的选项，这些kwargs将通过**Dumps_kwargs传递给json.ump。然而，在PYDNIC v2中，如果您尝试向BaseModel.json()添加额外的kwarg，则会失败，并显示错误TypeError：不再支持`Dumps_kwargs`关键字参数。

Here is example code with a workaround using dict()/model_dump(). This is good enough as long as the types are simple, but it won't work for the more complex data types that pydantic knows how to serialize.

以下是使用dict()/Model_Dump()解决办法的示例代码。只要类型很简单，这就足够好了，但是它不适用于更复杂的数据类型，因为它知道如何序列化。

Is there a way to get sort_keys to work in pydantic v2 in general?

有没有一种方法可以让SORT_KEYS在PYDNIC v2中正常工作？

import json
from pydantic import BaseModel


class JsonTest(BaseModel):
    b_field: int
    a_field: str

obj = JsonTest(b_field=1, a_field="one")

# this worked in pydantic v1 but raises a TypeError in v2
# print(obj.json(sort_keys=True)

print(obj.model_dump_json())
# {"b_field":1,"a_field":"one"}

# workaround for simple objects
print(json.dumps(obj.model_dump(), sort_keys=True))
# {"a_field": "one", "b_field": 1}

I'm not sure whether it is an elegant solution but you could leverage the fact that dictionaries (since python 3.7) preserve an order of elements:

我不确定这是否是一个优雅的解决方案，但您可以利用这样一个事实，即字典(从Python3.7开始)保留元素的顺序：

from typing import Any, Dict
from pydantic import BaseModel, model_serializer


class JsonTest(BaseModel):
    b_field: int
    c_field: int
    a_field: str

    @model_serializer(when_used='json')
    def sort_model(self) -> Dict[str, Any]:
        return dict(sorted(self.model_dump().items()))


obj = JsonTest(b_field=1, a_field="one", c_field=0)
print(obj.model_dump_json())
# {"a_field":"one","b_field":1,"c_field":0}

Hi!

嗨!

Try using the model_dump method and the sort_keys parameter of json.dumps to achieve sorting of keys in the JSON output in pydantic v2.

尝试使用json.dups的MODEL_DUMP方法和SORT_KEYS参数来实现对PYDINCTIONv2中的JSON输出中的键进行排序。

import json
from pydantic import BaseModel

class JsonTest(BaseModel):
    b_field: int
    a_field: str

obj = JsonTest(b_field=1, a_field="one")

# Use the model_dump method to get a dictionary and then sort the keys
sorted_json = json.dumps(obj.model_dump(), sort_keys=True)

print(sorted_json)
# {"a_field": "one", "b_field": 1}

This will produce a JSON striing with sorted keys. The model_dump method returns a dictionary representation of the Pydantic model, and then json.dumps is used with the sort_keys=True parameter to sort the keys alphabeticaly in the resulting JSON string.

这将产生带有已排序键的JSON竞争。MODEL_DUMP方法返回PYDANIC模型的字典表示，然后将json.dups与SORT_KEYS=True参数一起使用，按字母顺序对结果JSON字符串中的键进行排序。

You can read more here: https://docs.pydantic.dev/latest/usage/serialization/

你可以在这里阅读更多内容：https://docs.pydantic.dev/latest/usage/serialization/