Made it possible to register and run callbacks after a database
transaction is committed with the `transaction.on_commit()` function.
This patch is heavily based on Carl Meyers django-transaction-hooks
<https://django-transaction-hooks.readthedocs.org/>. Thanks to
Aymeric Augustin, Carl Meyer, and Tim Graham for review and feedback.
The primary use case is to interact with a third-party database (not
primarily managed by Django) that doesn't support time zones and where
datetimes are stored in local time when USE_TZ is True.
Configuring a PostgreSQL database with the TIME_ZONE option while USE_TZ
is False used to result in silent data corruption. Now this is an error.
Refs #23820.
Fixed#19738.
Refs #17755. In order not to introduce a regression for raw queries,
parameters are passed through the connection.ops.value_to_db_* methods,
depending on their type.
Field.rel is now deprecated. Rel objects have now also remote_field
attribute. This means that self == self.remote_field.remote_field.
In addition, made the Rel objects a bit more like Field objects. Still,
marked ManyToManyFields as null=True.
The new signature enables better support for routing RunPython and
RunSQL operations, especially w.r.t. reusable and third-party apps.
This commit also takes advantage of the deprecation cycle for the old
signature to remove the backward incompatibility introduced in #22583;
RunPython and RunSQL won't call allow_migrate() when when the router
has the old signature.
Thanks Aymeric Augustin and Tim Graham for helping shape up the patch.
Refs 22583.
As suggested by Anssi. This has the slightly strange side effect of
passing the expression to Expression.convert_value has the expression
passed back to it, but it allows more complex patterns of expressions.
Several issues resolved here, following from a report that a base_field
of GenericIpAddressField was failing.
We were using get_prep_value instead of get_db_prep_value in ArrayField
which was bypassing any extra modifications to the value being made in
the base field's get_db_prep_value. Changing this broke datetime
support, so the postgres backend has gained the relevant operation
methods to send dates/times/datetimes directly to the db backend instead
of casting them to strings. Similarly, a new database feature has been
added allowing the uuid to be passed directly to the backend, as we do
with timedeltas.
On the other side, psycopg2 expects an Inet() instance for IP address
fields, so we add a value_to_db_ipaddress method to wrap the strings on
postgres. We also have to manually add a database adapter to psycopg2,
as we do not wish to use the built in adapter which would turn
everything into Inet() instances.
Thanks to smclenithan for the report.
Andreas Pelme
Tim Graham
Ian Foote
Shai Berger
Matthew Somerville
Jon Dufresne
Josh Smeaton
Andriy Sokolovskiy
Aymeric Augustin
Claude Paroz
Simon Charette
Anssi Kääriäinen
Jean-Louis Fuchs
László Károlyi
Michael Manfre
Loic Bistuer
Marc Tamlyn
Collin Anderson
Andriy Sokolovskiy
Adam Taylor
Markus Holtermann