FilePathField loses required argument in init

[radekwlsk]

As FilePathField takes required keyword argument explicitly (to be passed to the DjagnoFilePathField used to build choices) it then "loses" it before calling the super().__init__(**kwargs).

Therefore with:

from rest_framework import serializers


class PathSerializer(serializers.Serializer):
    path = serializers.FilePathField(path="/usr/local", required=False)

we get bizzare result of:

>>> serializer = PathSerializer()
>>> serializer
PathSerializer():
    path = FilePathField(path='/usr/local', required=False)
>>> serializer.fields["path"].required
True

Expected behaviour would be to add the required argument to super init call as well, not only DjagnoFilePathField, like so:

class FilePathField(ChoiceField):
    default_error_messages = {
        'invalid_choice': _('"{input}" is not a valid path choice.')
    }

    def __init__(self, path, match=None, recursive=False, allow_files=True,
                 allow_folders=False, required=None, **kwargs):
        # Defer to Django's FilePathField implementation to get the
        # valid set of choices.
        field = DjangoFilePathField(
            path, match=match, recursive=recursive, allow_files=allow_files,
            allow_folders=allow_folders, required=required
        )
        kwargs['choices'] = field.choices
        # Pass required to field arguments
        kwargs['required'] = required
        super().__init__(**kwargs)

I would be more than happy to open a PR for that.

[auvipy]

you can come with a PR and ping me to fix the bug

[radekwlsk]

At the same time, I would suggest that path should be allowed to be a callable so it can be dynamically calculated and would be easier to mock in tests.

[radekwlsk]

@auvipy PR ready #8805

[auvipy]

thanks