"unknown" option should apply to nested fields

[zhengxiongzhao]

default at parser instantiation does not apply to nested fields, unless the nested schema(s) have the desired ma.EXCLUDE setting .

# No Working
parser = Parse(unknown=ma.EXCLUDE)
parser.parse({
            "book": fields.Nested(
                {
                    'id': fields.Str(),
                    'author': fields.Str(required=True)
                },
            )
        }, request)
}

# Working
parser.parse({
            "book": fields.Nested(
                {
                    'id': fields.Str(),
                    'author': fields.Str(required=True)
                },
                unknown=ma.EXCLUDE
            )
        }, request)
}

[lafrech]

Related to

• RFC: Propagate unknown value through nested schemas?  marshmallow#980
• "unknown" option should apply to nested fields so that "exclude" works marshmallow#1490
• unknown parameter passed to load method is not popagated to nested schema field. marshmallow#1428

[zhengxiongzhao]

Related to

• RFC: Propagate unknown value through nested schemas?  marshmallow#980
• "unknown" option should apply to nested fields so that "exclude" works marshmallow#1490
• unknown parameter passed to load method is not popagated to nested schema field. marshmallow#1428

Yes thanks I also noticed these problems

[sirosen]

I think marshmallow should support propagation of this setting as an opt-in flag, but that's a marshmallow matter, not a webargs one. I can't think of anything appropriate for webargs itself to do to better support this case.

@zhengxiongzhao, I'm confused about what sort of resolution you're looking for from webargs here? Or are you asking for advice about how to work around this limitation?

[sirosen]

Absent any possible action for us within webargs, I'm going to close this.

This is surprising for users, and I think it's bad that there's no ready answer other than "yes" or "use a schema factory". But it needs resolution upstream.