Django 4.2 major features ¶

pyscopg3 support ¶

Django now supports psycopg version 3.1.8 or higher.

To update your code, install the psycopg library, you don’t need to change the ENGINE as django.db.backends.postgresql supports both libraries.

Support for psycopg2 is likely to be deprecated and removed at some point in the future.

Example with poetry

❯ poetry add psycopg

           Using version ^3.1.8 for psycopg

Updating dependencies
Resolving dependencies... (0.5s)

Writing lock file

Package operations: 1 install, 0 updates, 0 removals

  • Installing psycopg (3.1.8)

✦ ❯ poetry remove psycopg2-binary

           Updating dependencies
Resolving dependencies... (0.4s)

Writing lock file

Package operations: 0 installs, 0 updates, 1 removal

  • Removing psycopg2-binary (2.9.6)

What’s new in Psycopg 3 ¶

https://www.psycopg.org/psycopg3/docs/basic/from_pg2.html#what-s-new-in-psycopg-3

Comments on columns and tables ¶

https://docs.djangoproject.com/en/4.2/releases/4.2/#comments-on-columns-and-tables

The new Field.db_comment and Meta.db_table_comment options allow creating comments on columns and tables, respectively.

Custom file storages (STORAGES) ¶

The new STORAGES setting allows configuring multiple custom file storage backends.

It also controls storage engines for managing files (the “default” key) and static files (the “staticfiles” key).

The old DEFAULT_FILE_STORAGE and STATICFILES_STORAGE settings are deprecated as of this release.

STORAGES

New in Django 4.2:

           Default:

STORAGES = {
    "default": {
        "BACKEND": "django.core.files.storage.FileSystemStorage",
    },
    "staticfiles": {
        "BACKEND": "django.contrib.staticfiles.storage.StaticFilesStorage",
    },
}

          

Upgrade with django-upgrade ¶

            django-upgrade --target-version 4.2 config/settings/base.py

           

            STORAGES = {
    "staticfiles": {
        "BACKEND": "django.contrib.staticfiles.storage.StaticFilesStorage",
    },
}

           

Warning

do not forget

            "default": {
    "BACKEND": "django.core.files.storage.FileSystemStorage",
},

           

Support for asynchronous streaming responses ¶

https://docs.djangoproject.com/en/4.2/releases/4.2/#requests-and-responses