Add serializer method field with params

[SergeiVElfimov]

Description

Hello dear maintainers, it's my first contribution to django rest framework so I hope I haven't done anything wrong.

I often encounter the need of reusing an existing method for a SerializerMethodField field with additional parameters.

Therefore, I decided to inherit from the SerializerMethodField class and pass the arguments included in the class to the method for greater flexibility.

For example:

class ExampleSerializer(Serializer):
        extra_info_bar_1 = SerializerMethodWithParamsField(method_name='foo', bar='bar_1', ...)
        extra_info_bar_2 = SerializerMethodWithParamsField(method_name='foo', bar='bar_2', ...)

        def foo(self, obj, **kwargs):
            bar = kwargs.get('bar', None)
            return str(obj) + bar

Thanks for reading and please let me know if there are any changes that could be made.

[auvipy]

do we really need this in the DRF core?

[SergeiVElfimov]

@auvipy Why not? It seems to me a very useful feature.

[kevin-brown]

I believe the current stance is that if it can be a third party package, it's better to have it as one. The DRF core changes slowly and hasn't really changed much in the past years, so you're better off having stuff like this in one of the faster moving external packages.

[SergeiVElfimov]

@kevin-brown Thanks for the detailed answer. I am very sorry that the changes to the DRF core slowly, because I think one of the best projects. I'm closing pull request.