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}
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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
.
这将生成一个带有排序键的JSON字符串。model_dump方法返回Pydantic模型的字典表示,然后使用json.dumps和sort_keys=True参数对结果JSON字符串中的键进行分类。
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/
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yes, that's the workaround i posted i the original question. i was hoping there was a more robust solution that could handle the additional dtypes that pydantic can do docs.pydantic.dev/2.3/usage/serialization/#modelmodel_dump_json
是的,这就是我在原始问题中发布的解决方法。我希望有一种更健壮的解决方案,可以处理PYDINIC可以处理docs.pydantic.dev/2.3/usage/serialization/#modelmodel_dump_json的额外数据类型
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