Django MongoDB Backend 5.1.x¶

5.1.0 beta 4¶

August 13, 2025

Backward-incompatible: Removed support for database caching as the MongoDB security team considers the cache backend’s pickle encoding of cached values a vulnerability. If an attacker compromises the database, they could run arbitrary commands on the application server.
Fixed crash when loading models with a null value for ArrayFields where the base_field uses a database converter.
Fixed RecursionError when using Trunc database functions on non-MongoDB databases.
Improved QuerySet performance by removing low limit on server-side chunking.

May 14, 2025

Added support for a field’s custom lookups and transforms in EmbeddedModelField, e.g. ArrayField’s contains, contained__by, len, etc.
Fixed the results of queries that use the tzinfo parameter of the Trunc database functions.
Added support for QuerySet.dates() and datetimes().
Fixed loading of QuerySet results for embedded models that have fields that use database converters. For example, a crash for DecimalField: ValidationError: ['“1” value must be a decimal number.']).

April 21, 2025

Backward-incompatible: ArrayField's size parameter is renamed to max_size. The size parameter is now used to enforce fixed-length arrays.
Added support for database caching (later removed in beta 4).
Fixed QuerySet.raw_aggregate() field initialization when the document key order doesn’t match the order of the model’s fields.

February 26, 2025

Backward-incompatible: ObjectIdAutoField no longer accepts integer values. The undocumented behavior eased testing with Django’s test suite which hardcodes many integer primary key values.
Fixed the inability to save nested embedded model forms.
Fixed persistent database connections.
Added async support.
Added the db_name parameter to parse_uri().
Added django_mongodb_backend.routers.MongoRouter to allow dumpdata to ignore embedded models. See Configuring the DATABASE_ROUTERS setting.

January 30, 2025

Initial Public Preview release.