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marshmallow: simplified object serialization

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|pypi| |build-status| |pre-commit| |docs|

.. |pypi| image:: https://badgen.net/pypi/v/marshmallow :target: https://pypi.org/project/marshmallow/ :alt: Latest version

.. |build-status| image:: https://github.com/marshmallow-code/marshmallow/actions/workflows/build-release.yml/badge.svg :target: https://github.com/marshmallow-code/marshmallow/actions/workflows/build-release.yml :alt: Build status

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.. |docs| image:: https://readthedocs.org/projects/marshmallow/badge/ :target: https://marshmallow.readthedocs.io/ :alt: Documentation

.. start elevator-pitch

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

.. code-block:: python

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

.. code-block:: shell-session

$ pip install -U marshmallow

.. end elevator-pitch

Documentation

Full documentation is available at https://marshmallow.readthedocs.io/ .

Ecosystem

A list of marshmallow-related libraries can be found at the GitHub wiki here:

https://github.com/marshmallow-code/marshmallow/wiki/Ecosystem

Credits

Contributors

This project exists thanks to all the people who contribute.

You're highly encouraged to participate in marshmallow's development. Check out the Contributing Guidelines <https://marshmallow.readthedocs.io/en/latest/contributing.html>_ to see how you can help.

Thank you to all who have already contributed to marshmallow!

.. image:: https://opencollective.com/marshmallow/contributors.svg?width=890&button=false :target: https://marshmallow.readthedocs.io/en/latest/authors.html :alt: Contributors

Backers

If you find marshmallow useful, please consider supporting the team with a donation. Your donation helps move marshmallow forward.

Thank you to all our backers! [Become a backer_]

.. _Become a backer: https://opencollective.com/marshmallow#backer

.. image:: https://opencollective.com/marshmallow/backers.svg?width=890 :target: https://opencollective.com/marshmallow#backers :alt: Backers

Sponsors

.. start sponsors

marshmallow is sponsored by Route4Me <https://route4me.com>_.

.. image:: https://github.com/user-attachments/assets/018c2e23-032e-4a11-98da-8b6dc25b9054 :target: https://route4me.com :alt: Routing Planner

Support this project by becoming a sponsor (or ask your company to support this project by becoming a sponsor). Your logo will be displayed here with a link to your website. [Become a sponsor_]

.. _Become a sponsor: https://opencollective.com/marshmallow#sponsor

.. end sponsors

Professional Support

Professionally-supported marshmallow is now available through the Tidelift Subscription <https://tidelift.com/subscription/pkg/pypi-marshmallow?utm_source=pypi-marshmallow&utm_medium=readme>_.

Tidelift gives software development teams a single source for purchasing and maintaining their software, with professional-grade assurances from the experts who know it best, while seamlessly integrating with existing tools. [Get professional support_]

.. _Get professional support: https://tidelift.com/subscription/pkg/pypi-marshmallow?utm_source=marshmallow&utm_medium=referral&utm_campaign=github

.. image:: https://user-images.githubusercontent.com/2379650/45126032-50b69880-b13f-11e8-9c2c-abd16c433495.png :target: https://tidelift.com/subscription/pkg/pypi-marshmallow?utm_source=pypi-marshmallow&utm_medium=readme :alt: Get supported marshmallow with Tidelift

Project Links

• Docs: https://marshmallow.readthedocs.io/
• Changelog: https://marshmallow.readthedocs.io/en/latest/changelog.html
• Contributing Guidelines: https://marshmallow.readthedocs.io/en/latest/contributing.html
• PyPI: https://pypi.org/project/marshmallow/
• Issues: https://github.com/marshmallow-code/marshmallow/issues
• Donate: https://opencollective.com/marshmallow

License

MIT licensed. See the bundled LICENSE <https://github.com/marshmallow-code/marshmallow/blob/dev/LICENSE>_ file for more details.