marshmallow: simplified object serialization

Release v3.23.1. (Changelog)

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marshmallow is an ORM/ODM/framework-agnostic library for converting complex datatypes, such as objects, to and from native Python datatypes.

from datetime import date
from pprint import pprint

from marshmallow import Schema, fields


class ArtistSchema(Schema):
    name = fields.Str()


class AlbumSchema(Schema):
    title = fields.Str()
    release_date = fields.Date()
    artist = fields.Nested(ArtistSchema())


bowie = dict(name="David Bowie")
album = dict(artist=bowie, title="Hunky Dory", release_date=date(1971, 12, 17))

schema = AlbumSchema()
result = schema.dump(album)
pprint(result, indent=2)
# { 'artist': {'name': 'David Bowie'},
#   'release_date': '1971-12-17',
#   'title': 'Hunky Dory'}

In short, marshmallow schemas can be used to:

  • Validate input data.

  • Deserialize input data to app-level objects.

  • Serialize app-level objects to primitive Python types. The serialized objects can then be rendered to standard formats such as JSON for use in an HTTP API.

Get It Now

$ pip install -U marshmallow

Ready to get started? Go on to the Quickstart tutorial or check out some Examples.

Upgrading from an older version?

See the Upgrading to Newer Releases page for notes on getting your code up-to-date with the latest version.

Why another library?

See this document to learn about what makes marshmallow unique.

Sponsors

marshmallow is sponsored by Route4Me.

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