django-sortedm2m 4.0.0
Drop-in replacement for Django's many to many field with sorted relations.
License: BSD

================
django-sortedm2m
================

.. image:: https://jazzband.co/static/img/badge.svg
   :target: https://jazzband.co/
   :alt: Jazzband

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   :target: https://pypi.python.org/pypi/django-sortedm2m
   :alt: PyPI Release

.. image:: https://github.com/jazzband/django-sortedm2m/actions/workflows/test.yml/badge.svg?branch=master
   :target: https://github.com/jazzband/django-sortedm2m/actions?query=branch%3Amaster
   :alt: Build Status

.. image:: https://codecov.io/gh/jazzband/django-sortedm2m/branch/master/graph/badge.svg
   :target: https://codecov.io/gh/jazzband/django-sortedm2m
   :alt: Code coverage

``sortedm2m`` is a drop-in replacement for django's own ``ManyToManyField``.
The provided ``SortedManyToManyField`` behaves like the original one but
remembers the order of added relations.

Use Cases
=========

Imagine that you have a gallery model and a photo model. Usually you want a
relation between these models so you can add multiple photos to one gallery
but also want to be able to have the same photo on many galleries.

This is where you usually can use many to many relation. The downside is that
django's default implementation doesn't provide a way to order the photos in
the gallery. So you only have a random ordering which is not suitable in most
cases.

You can work around this limitation by using the ``SortedManyToManyField``
provided by this package as drop in replacement for django's
``ManyToManyField``.

Requirements
============

**django-sortedm2m** runs on Python 3.6+ and multiple Django versions.
See the ``.github/workflows/test.yml`` configuration for the tested Django versions.

Usage
=====

Use ``SortedManyToManyField`` like ``ManyToManyField`` in your models:

.. code-block:: python

    from django.db import models
    from sortedm2m.fields import SortedManyToManyField

    class Photo(models.Model):
        name = models.CharField(max_length=50)
        image = models.ImageField(upload_to='...')

    class Gallery(models.Model):
        name = models.CharField(max_length=50)
        photos = SortedManyToManyField(Photo)

If you use the relation in your code like the following, it will remember the
order in which you have added photos to the gallery. :

.. code-block:: python

    gallery = Gallery.objects.create(name='Photos ordered by name')
    for photo in Photo.objects.order_by('name'):
        gallery.photos.add(photo)

``SortedManyToManyField``
-------------------------

You can use the following arguments to modify the default behavior:

``sorted``
~~~~~~~~~~

**Default:** ``True``

You can set the ``sorted`` to ``False`` which will force the
``SortedManyToManyField`` in behaving like Django's original
``ManyToManyField``. No ordering will be performed on relation nor will the
intermediate table have a database field for storing ordering information.

``sort_value_field_name``
~~~~~~~~~~~~~~~~~~~~~~~~~

**Default:** ``'sort_value'``

Specifies how the field is called in the intermediate database table by which
the relationship is ordered. You can change its name if you have a legacy
database that you need to integrate into your application.

``base_class``
~~~~~~~~~~~~~~

**Default:** ``None``

You can set the ``base_class``, which is the base class of the through model of
the sortedm2m relationship between models to an abstract base class containing
a ``__str__`` method to improve the string representations of sortedm2m
relationships.

.. note::

    You also could use it to add additional fields to the through model. But
    please beware: These fields will not be created or modified by an
    automatically created migration. You will need to take care of migrations
    yourself. In most cases when you want to add another field, consider
    *not* using sortedm2m but use a ordinary Django ManyToManyField and
    specify `your own through model`_.

.. _your own through model: https://docs.djangoproject.com/en/1.11/ref/models/fields/#django.db.models.ManyToManyField.through

Migrating a ``ManyToManyField`` to be a ``SortedManyToManyField``
=================================================================

If you are using Django's migration framework and want to change a
``ManyToManyField`` to be a ``SortedManyToManyField`` (or the other way
around), you will find that a migration created by Django's ``makemigrations``
will not work as expected.

In order to migrate a ``ManyToManyField`` to a ``SortedManyToManyField``, you
change the field in your models to be a ``SortedManyToManyField`` as
appropriate and create a new migration with ``manage.py makemigrations``.
Before applying it, edit the migration file and change in the ``operations``
list ``migrations.AlterField`` to ``AlterSortedManyToManyField`` (import it
from ``sortedm2m.operations``).  This operation will take care of changing the
intermediate tables, add the ordering field and fill in default values.

Admin
=====

``SortedManyToManyField`` provides a custom widget which can be used to sort
the selected items. It renders a list of checkboxes that can be sorted by
drag'n'drop.

To use the widget in the admin you need to add ``sortedm2m`` to your
INSTALLED_APPS settings, like:

.. code-block:: python

   INSTALLED_APPS = (
       'django.contrib.auth',
       'django.contrib.contenttypes',
       'django.contrib.sessions',
       'django.contrib.sites',
       'django.contrib.messages',
       'django.contrib.staticfiles',
       'django.contrib.admin',

       'sortedm2m',

       '...',
   )

Otherwise it will not find the css and js files needed to sort by drag'n'drop.

Finally, make sure *not* to have the model listed in any ``filter_horizontal``
or ``filter_vertical`` tuples inside of your ``ModelAdmin`` definitions.

If you did it right, you'll wind up with something like this:

.. image:: http://i.imgur.com/HjIW7MI.jpg

It's also possible to use the ``SortedManyToManyField`` with admin's
``raw_id_fields`` option in the ``ModelAdmin`` definition. Add the name of the
``SortedManyToManyField`` to this list to get a simple text input field. The
order in which the ids are entered into the input box is used to sort the
items of the sorted m2m relation.

Example:

.. code-block:: python

    from django.contrib import admin

    class GalleryAdmin(admin.ModelAdmin):
        raw_id_fields = ('photos',)

Contribute
==========
This is a `Jazzband <https://jazzband.co>`_ project. By contributing you agree to abide by the
`Contributor Code of Conduct <https://jazzband.co/about/conduct>`_ and follow the
`guidelines <https://jazzband.co/about/guidelines>`_.

You can find the latest development version on Github_. Get there and fork it, file bugs or send well wishes.

.. _github: http://github.com/jazzband/django-sortedm2m

Running the tests
-----------------

I recommend to use ``tox`` to run the tests for all relevant python versions
all at once. Therefore install ``tox`` with ``pip install tox``, then type in
the root directory of the ``django-sortedm2m`` checkout::

   tox

The tests are run against SQLite, then against PostgreSQL, then against mySQL -
so you need to install PostgreSQL and mySQL on your dev environment, and should
have a role/user ``sortedm2m`` set up for both PostgreSQL and mySQL.

Code Quality
------------
This project uses `isort <https://github.com/timothycrosley/isort>`_, `pycodestyle <https://github.com/PyCQA/pycodestyle>`_,
and `pylint <https://www.pylint.org>`_ to manage validate code quality. These validations can be run with the
following command::

   tox -e quality


Changelog
=========

4.0.0
-----
* `#216`_: Dropped support for outdated versions of Django and Python
* `#215`_: Added support for Django 5.1

.. _#215: https://github.com/jazzband/django-sortedm2m/pull/215
.. _#216: https://github.com/jazzband/django-sortedm2m/pull/215

3.1.1
-----
* `#191`_: Fixed JS bug for popup in Django admin

.. _#191: https://github.com/jazzband/django-sortedm2m/pull/191

3.1.0
-----
* `#178`_: Bug fixes
* `#178`_: Fixed Pylint error
* `#175`_: Fixed jQuery UI error
* `#183`_: Migrated to GitHub Actions for CI
* `#184`_: Added support for Django 3.2

.. _#170: https://github.com/jazzband/django-sortedm2m/pull/170
.. _#178: https://github.com/jazzband/django-sortedm2m/pull/178
.. _#175: https://github.com/jazzband/django-sortedm2m/pull/175
.. _#183: https://github.com/jazzband/django-sortedm2m/pull/183
.. _#184: https://github.com/jazzband/django-sortedm2m/pull/184

3.0.2
-----
* `#168`_: Restored `admin/js/jquery.init.js`

.. _#168: https://github.com/jazzband/django-sortedm2m/pull/168

3.0.1
-----
* `#164`_: Added all locales to distributable
* `#162`_: Added missing files to MANIFEST.in, and removed .DS_Store files
* `#150`_: Added German and Spanish translations
* `#149`_: Removed `admin/js/jquery.init.js` from `SortedCheckboxSelectMultiple`

.. _#164: https://github.com/jazzband/django-sortedm2m/pull/164
.. _#162: https://github.com/jazzband/django-sortedm2m/pull/162
.. _#150: https://github.com/jazzband/django-sortedm2m/pull/150
.. _#149: https://github.com/jazzband/django-sortedm2m/pull/149

3.0.0
-----
* `#147`_: Dropped support for Django 2.0
* `#152`_: Dropped support for Django 1.10
* `#152`_: Add support for Python 3.8
* `#152`_: Add support for Django 3.0

.. _#147: https://github.com/jazzband/django-sortedm2m/issues/147
.. _#152: https://github.com/jazzband/django-sortedm2m/issues/152

2.0.0
-----
* `#135`_: Updated README with Jazzband details, and added CONTRIBUTING.md
* `#136`_: Dropped support for Python 2.6 and 3.3, and Django < 1.11
* `#130`_: Added support for Python 3.7 and Django 2.0 to 2.2
* `#130`_: Add support of custom through models (only for Django >= 2.2)
* `#138`_: Added coverage reporting

.. _#130: https://github.com/jazzband/django-sortedm2m/issues/130
.. _#135: https://github.com/jazzband/django-sortedm2m/pull/135
.. _#136: https://github.com/jazzband/django-sortedm2m/pull/136
.. _#138: https://github.com/jazzband/django-sortedm2m/pull/138

1.5.0
-----

* `#101`_: Add support for a custom base class for the many to many intermediate
  class. See the README for documentation. Thank you Rohith Asrk for the patch.
* `#87`_: Fix ``AlterSortedManyToManyField`` operation to support custom set
  ``_sort_field_name``.

.. _#101: https://github.com/jazzband/django-sortedm2m/pull/101
.. _#87: https://github.com/jazzband/django-sortedm2m/issues/87

1.4.0
-----

* `#104`_: Add compatibility for Django 1.10 and 1.11!
  Thank you Frankie Dintino for the patch.
* `#94`_: Add french translation files. Mainly for strings in the admin.
  Thanks to ppython for the patch.
* `#93`_: Prevent users from accidentally importing and using
  ``ManyToManyField`` instead of ``SortedManyToManyField`` from ``sortedm2m``.
  Thanks Dayne May for the patch.

.. _#104: https://github.com/jazzband/django-sortedm2m/pull/104
.. _#94: https://github.com/jazzband/django-sortedm2m/pull/94
.. _#93: https://github.com/jazzband/django-sortedm2m/pull/93

1.3.3
-----

* `#91`_ & `#92`_: Fix admin widget, when used with Django 1.10. The add a new
  item opup was not closing. Thanks to Tipuch for the patch.

.. _#91: https://github.com/jazzband/django-sortedm2m/issues/91
.. _#92: https://github.com/jazzband/django-sortedm2m/pull/92

1.3.2
-----

* `#80`_ & `#83`_: Fix ``SortedMultipleChoiceField.clean`` if the validated
  value is ``None``. Thanks to Alex Mannhold for the patch.

.. _#80: https://github.com/jazzband/django-sortedm2m/issues/80
.. _#83: https://github.com/jazzband/django-sortedm2m/pull/83

1.3.1
-----

* `#57`_ & `#81`_: Fix add related object popup error prevents operation when
  no related objects already exist. Thanks to Vadim Sikora for the fix.

.. _#57: https://github.com/jazzband/django-sortedm2m/issue/57
.. _#81: https://github.com/jazzband/django-sortedm2m/pull/81

1.3.0
-----

* `#79`_: Use `.sortedm2m-item` selector in the widget's JavaScript code to
  target the list items. This was previously `ul.sortedm2m li`. This improves
  compatibility other markup that does not want to use `ul`/`li` tags. Thanks
  to Michal Dabski for the patch.

  **Note:** If you use custom markup with the JavaScript code, you need to make
  sure that the items now have the `sortedm2m-item` class name.

* `#76`_: Add support for to_field_name to SortedMultipleChoiceField. Thanks
  to Conrad Kramer for the patch.

.. _#76: https://github.com/jazzband/django-sortedm2m/pull/76
.. _#79: https://github.com/jazzband/django-sortedm2m/pull/79

1.2.2
-----

* `#75`_: Fix "add another" admin popup. It didn't refresh the list of items in Django
  1.8+. Thanks to Vadim Sikora for the patch.

.. _#75: https://github.com/jazzband/django-sortedm2m/pull/75

1.2.1
-----

* *skipped*

1.2.0
-----

* Dropping Python 3.2 support. It has reached end of life in February 2016.

1.1.2
-----

* `#71`_: Don't break collectstatic for some cases. Therefore we removed the
  STATIC_URL prefix from the form media definition in
  ``SortedCheckboxSelectMultiple``. Thanks to Kirill Ermolov for the
  patch.

.. _#71: https://github.com/jazzband/django-sortedm2m/issues/71

1.1.1
-----

* `#70`_: CSS fix for Django 1.9 new admin design. Thanks to Maarten Draijer
  for the patch.

.. _#70: https://github.com/jazzband/django-sortedm2m/pull/70

1.1.0
-----

* `#59`_, `#65`_, `#68`_: Django 1.9 support. Thanks to Scott Kyle and Jasper Maes for
  patches.
* `#67`_: Support for disabling migrations for some models, that can be
  decided by Django's DB router (with the ``allow_migrate_model`` method).
  Thanks to @hstanev for the patch.

.. _#59: https://github.com/jazzband/django-sortedm2m/pull/59
.. _#65: https://github.com/jazzband/django-sortedm2m/pull/65
.. _#67: https://github.com/jazzband/django-sortedm2m/pull/67
.. _#68: https://github.com/jazzband/django-sortedm2m/pull/68

1.0.2
-----

* `#56`_: Fix bug where order is wrong after adding objects. That had to do
  with using the ``count`` of the m2m objects for the next ``sort_value``
  value. We now use the corret ``Max`` aggregation to make sure that newly
  added objects will be in order. Thanks to Scott Kyle for the report and
  patch.

.. _#56: https://github.com/jazzband/django-sortedm2m/pull/56

1.0.1
-----

* Performance fix for sorted m2m admin widget. See `#54`_ for details. Thanks
  to Jonathan Liuti for fixing this.

.. _#54: https://github.com/jazzband/django-sortedm2m/pull/54

1.0.0
-----

* Hooray, we officially declare **django-sortedm2m** to be stable and
  promise to be backwards compatible to new releases (we already doing good
  since since the beginning in that regard).
* Django 1.8 support for ``AlterSortedManyToManyField`` operation. Thanks to
  Nicolas Trésegnie for starting the implementation.

0.10.0
------

* The creation of the sortedm2m intermediate model and database table is now
  fully done inside of the ``SortedManyToManyField`` class. That makes it much
  easier to modify the creation of this when creating a custom subclass of this
  field. See `#49`_ for an example usecase.
* Adding support for the custom field arguments like ``sorted`` and
  ``sort_value_field_name`` in Django 1.7 migrations. Thanks to Christian
  Kohlstedde for the patch.

.. _#49: https://github.com/jazzband/django-sortedm2m/issues/49

0.9.5
-----

* Fixing ``setup.py`` when run on a system that does not use UTF-8 as default
  encoding. See `#48`_ for details. Thanks to Richard Mitchell for the patch.

.. _#48: https://github.com/jazzband/django-sortedm2m/pull/48

0.9.4
-----

* Fix: ``SortedMultipleChoiceField`` did not properly report changes of the
  data to ``Form.changed_data``. Thanks to @smcoll for the patch.

0.9.3
-----

* Fix: ``AlterSortedManyToManyField`` operation failed for postgres databases.
* Testing against MySQL databases.

0.9.2
-----

* Fix: ``AlterSortedManyToManyField`` operation failed for many to many fields
  which already contained some data.

0.9.1
-----

* Fix: When using the sortable admin widget, deselecting an item in the list
  had not effect. Thank you to madEng84 for the report and patch!

0.9.0
-----

* Adding ``AlterSortedManyToManyField`` migration operation that allows you to
  migrate from ``ManyToManyField`` to ``SortedManyToManyField`` and vice
  versa. Thanks to Joaquín Pérez for the patch!
* Fix: Supporting migrations in Django 1.7.4.
* Fix: The admin widget is not broken anymore for dynamically added inline
  forms. Thanks to Rubén Díaz for the patch!

0.8.1
-----

* Adding support for Django 1.7 migrations. Thanks to Patryk Hes and Richard
  Barran for their reports.
* Adding czech translations. Thanks to @cuchac for the pull request.

0.8.0
-----

* Adding support for Django 1.7 and dropping support for Django 1.4.

0.7.0
-----

* Adding support for ``prefetch_related()``. Thanks to Marcin Ossowski for
  the idea and patch.

0.6.1
-----

* Correct escaping of *for* attribute in label for the sortedm2m widget. Thanks
  to Mystic-Mirage for the report and fix.

0.6.0
-----

* Python 3 support!
* Better widget. Thanks to Mike Knoop for the initial patch.

0.5.0
-----

* Django 1.5 support. Thanks to Antti Kaihola for the patches.
* Dropping Django 1.3 support. Please use django-sortedm2m<0.5 if you need to
  use Django 1.3.
* Adding support for a ``sort_value_field_name`` argument in
  ``SortedManyToManyField``. Thanks to Trey Hunner for the idea.

0.4.0
-----

* Django 1.4 support. Thanks to Flavio Curella for the patch.
* south support is only enabled if south is actually in your INSTALLED_APPS
  setting. Thanks to tcmb for the report and Florian Ilgenfritz for the patch.

0.3.3
-----

* South support (via monkeypatching, but anyway... it's there!). Thanks to
  Chris Church for the patch. South migrations won't pick up a changed
  ``sorted`` argument though.

0.3.2
-----

* Use already included jQuery version in global scope and don't override with
  django's version. Thank you to Hendrik van der Linde for reporting this
  issue.

0.3.1
-----

* Fixed packaging error.

0.3.0
-----

* Heavy internal refactorings. These were necessary to solve a problem with
  ``SortedManyToManyField`` and a reference to ``'self'``.

0.2.5
-----

* Forgot to exclude debug print/console.log statements from code. Sorry.

0.2.4
-----

* Fixing problems with ``SortedCheckboxSelectMultiple`` widget, especially in
  admin where a "create and add another item" popup is available.

0.2.3
-----

* Fixing issue with primary keys instead of model instances for ``.add()`` and
  ``.remove()`` methods in ``SortedRelatedManager``.

0.2.2
-----

* Fixing validation error for ``SortedCheckboxSelectMultiple``. It caused
  errors if only one value was passed.

0.2.1
-----

* Removed unnecessary reference of jquery ui css file in
  ``SortedCheckboxSelectMultiple``. Thanks to Klaas van Schelven and Yuwei Yu
  for the hint.

0.2.0
-----

* Added a widget for use in admin.