• Language: en
  • Documentation version: development

Django 2.2 release notes - UNDER DEVELOPMENT

Expected April 2019

Welcome to Django 2.2!

These release notes cover the new features, as well as some backwards incompatible changes you’ll want to be aware of when upgrading from Django 2.1 or earlier. We’ve begun the deprecation process for some features.

See the Upgrading Django to a newer version guide if you’re updating an existing project.

Django 2.2 is designated as a long-term support release. It will receive security updates for at least three years after its release. Support for the previous LTS, Django 1.11, will end in April 2020.

Python compatibility

Django 2.2 supports Python 3.5, 3.6, and 3.7. We highly recommend and only officially support the latest release of each series.

What’s new in Django 2.2

Check Constraints

The new CheckConstraint class enables adding custom database constraints. Constraints are added to models using the Meta.constraints option.

Minor features

django.contrib.gis

django.contrib.postgres

  • The new ordering argument for ArrayAgg and StringAgg determines the ordering of the aggregated elements.
  • The new BTreeIndex, HashIndex and SpGistIndex classes allow creating B-Tree, hash, and SP-GiST indexes in the database.
  • BrinIndex now has the autosummarize parameter.
  • The new search_type parameter of SearchQuery allows searching for a phrase or raw expression.

django.contrib.staticfiles

Cache

CSRF

Database backends

Email

File Storage

File Uploads

Forms

Generic Views

Internationalization

Management Commands

Migrations

  • The new migrate --plan option prints the list of migration operations that will be performed.
  • NoneType can now be serialized in migrations.

Models

  • Added support for PostgreSQL operator classes (Index.opclasses).
  • Added many math database functions.
  • Setting the new ignore_conflicts parameter of QuerySet.bulk_create() to True tells the database to ignore failure to insert rows that fail uniqueness constraints or other checks.
  • The new ExtractIsoYear function extracts ISO-8601 week-numbering years from DateField and DateTimeField, and the new iso_year lookup allows querying by an ISO-8601 week-numbering year.
  • The new QuerySet.bulk_update() method allows efficiently updating specific fields on multiple model instances.
  • Django no longer always starts a transaction when a single query is being performed, such as Model.save(), QuerySet.update(), and Model.delete(). This improves the performance of autocommit by reducing the number of database round trips.

Requests and Responses

Serialization

  • You can now deserialize data using natural keys containing forward references by passing handle_forward_references=True to serializers.deserialize(). Additionally, loaddata handles forward references automatically.

Signals

Templates

Tests

  • The new SimpleTestCase.assertURLEqual() assertion checks for a given URL, ignoring the ordering of the query string. assertRedirects() uses the new assertion.
  • The test Client now supports automatic JSON serialization of list and tuple data when content_type='application/json'.

URLs

Validators

Backwards incompatible changes in 2.2

Database backend API

  • Third-party database backends must implement support for table check constraints or set DatabaseFeatures.supports_table_check_constraints to False.
  • Third party database backends must implement support for ignoring constraints or uniqueness errors while inserting or set DatabaseFeatures.supports_ignore_conflicts to False.

django.contrib.gis

  • Support for GDAL 1.9 and 1.10 is dropped.

Miscellaneous

  • To improve readability, the UUIDField form field now displays values with dashes, e.g. 550e8400-e29b-41d4-a716-446655440000 instead of 550e8400e29b41d4a716446655440000.
  • On SQLite, PositiveIntegerField and PositiveSmallIntegerField now include a check constraint to prevent negative values in the database. If you have existing invalid data and run a migration that recreates a table, you’ll see CHECK constraint failed.
  • For consistency with WSGI servers, the test client now sets the Content-Length header to a string rather than an integer.
  • The return value of django.utils.text.slugify() is no longer marked as HTML safe.
  • The default truncation character used by the urlizetrunc, truncatechars, truncatechars_html, truncatewords, and truncatewords_html template filters is now the real ellipsis character () instead of 3 dots. You may have to adapt some test output comparisons.
  • Support for bytestring paths in the template filesystem loader is removed.
  • django.utils.http.urlsafe_base64_encode() now returns a string instead of a bytestring, and django.utils.http.urlsafe_base64_decode() may no longer be passed a bytestring.
  • Support for cx_Oracle < 6.0 is removed.

Features deprecated in 2.2

Model Meta.ordering will no longer affect GROUP BY queries

A model’s Meta.ordering affecting GROUP BY queries (such as .annotate().values()) is a common source of confusion. Such queries now issue a deprecation warning with the advice to add an order_by() to retain the current query. Meta.ordering will be ignored in such queries starting in Django 3.1.

Miscellaneous

  • django.utils.timezone.FixedOffset is deprecated in favor of datetime.timezone.
  • The undocumented QuerySetPaginator alias of django.core.paginator.Paginator is deprecated.
  • The FloatRangeField model and form fields in django.contrib.postgres are deprecated in favor of a new name, DecimalRangeField, to match the underlying numrange data type used in the database.
  • The FILE_CHARSET setting is deprecated. Starting with Django 3.1, files read from disk must be UTF-8 encoded.
Back to Top