Recipes

Various recipes and patterns for webargs.

Substitute for use=func in webargs>=0.16.0

For 0.16.0 onwards, use of marshmallow is encouraged. Marshmallow brings a whole slew of serialization/deserialization features, which is exactly what you're doing when you take web requests from various frameworks and turn them into native python data types: deserializing.

use= used to let you change the value of a field while it was parsed. You can accomplish that and more now with marshmallow's post_load decorator:

from marshmallow import Schema, post_load
from webargs import fields

class ArgSchema(Schema):
    name = fields.Str(required=True, location='querystring')

    @post_load
    def uppercase_name(self, data):
        data['name'] = data['name'].upper()
        return data

See the documentation for how to use marshmallow schemas in webargs.

Since you now have access to all fields in the data argument of your post_load method, you can do cross preprocessing, meaning you can change the value of one field based upon the value of another.

Credit: @dwieeb