引发与IntegrityError相关的异常时，获取字段名称的最pythonic方法是什么？

Question

I'm developing an API with DRF and I want to generate and return proper custom error messages when an exception related to IntegrityError is thrown.

To do this, I've implemented a custom exception handler. Inside the custom exception handler, I want to get the name of the field that causes the error from the Exception instance and then I'll generate and return proper message in the response.

Currently, I can do this by parsing the message attribute of the Exception instance but I'm not sure this is the best possible solution.

So, is there any pythonic way to get the name of the field from the Exception instance when an exception related to IntegrityError is thrown?

Thanks!

Answer 1

According to source it seems IntergityError is no more than an Exception so the only way is to parsing exception.message or exception.args .

You always can check what gives you print(dir(exception)) but I'm pretty sure only message and args will be helpful.

Answer 2

IMHO "parsing the message" is perfectly pythonic: simple, readable, you can do the same/similar solution in any other similar situation. I've seen something like this before:

# in a custom Serializer's create() method
try:
    return super().create(validated_data)
except IntegrityError as e:
    raise APIException(detail=e.args[0].split('DETAIL:  ')[1])

It simple, it works and getting the extra data in any other way will likely involve something significantly more complicated.