How do I deserialize a different structured JSON data in Marshmallow?

Question

I have a Schema as below:

from marshmallow import Schema, fields

class ContactSchema(Schema):
    # ... other fields ...
    phone = fields.Str()
    # ... other fields ...

However, JSON data I deal with is different:

{
    // ... other data ...
    "information": {
        "address": "foo",
        "email": "[email protected]",
        "phone": "+101234567890"
    }
    // .. other data ..
}

As you can see, phone key is under information, which is different than how ContactSchema is formed.

Can I, and how can I, map a Field under a Schema to a different path in target JSON data?

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Environment

• Python 3.5 and above
• Marshmallow 2.16.3

Answer 1

You can extend your schema and provide a pre_load method:

class ContactSchema(Schema):

    @preload
    def extract_information(self, data):
       # Please check for None's
       data['phone'] = data['information'].pop('phone')
       return data