This is provided as a new "validate_max" formset_factory option defaulting to
False, since the non-validating behavior of max_num is longstanding, and there
is certainly code relying on it. (In fact, even the Django admin relies on it
for the case where there are more existing inlines than the given max_num). It
may be that at some point we want to deprecate validate_max=False and
eventually remove the option, but this commit takes no steps in that direction.
This also fixes the DoS-prevention absolute_max enforcement so that it causes a
form validation error rather than an IndexError, and ensures that absolute_max
is always 1000 more than max_num, to prevent surprising changes in behavior
with max_num close to absolute_max.
Lastly, this commit fixes the previous inconsistency between a regular formset
and a model formset in the precedence of max_num and initial data. Previously
in a regular formset, if the provided initial data was longer than max_num, it
was truncated; in a model formset, all initial forms would be displayed
regardless of max_num. Now regular formsets are the same as model formsets; all
initial forms are displayed, even if more than max_num. (But if validate_max is
True, submitting these forms will result in a "too many forms" validation
error!) This combination of behaviors was chosen to keep the max_num validation
simple and consistent, and avoid silent data loss due to truncation of initial
data.
Thanks to Preston for discussion of the design choices.
MySQL accepts 0000-00-00 as a valid date but MySQLdb converts those
values into None. So there will be problems for instance if trying to
transport the data using dumpdata/loaddata.
This patch refs #6642 that has been closed as wontfix since this is a
particular problem of MySQL.
Model.save() will use UPDATE - if not updated - INSERT instead of
SELECT - if found UPDATE else INSERT. This should save a query when
updating, but will cost a little when inserting model with PK set.
Also fixed#17341 -- made sure .save() commits transactions only after
the whole model has been saved. This wasn't the case in model
inheritance situations.
The save_base implementation was refactored into multiple methods.
A typical chain for inherited save is:
save_base()
_save_parents(self)
for each parent:
_save_parents(parent)
_save_table(parent)
_save_table(self)
Replaced them with per-database options, for proper multi-db support.
Also toned down the recommendation to tie transactions to HTTP requests.
Thanks Jeremy for sharing his experience.
Squashed commit of the following:
commit 2181d833ed1a2e422494738dcef311164c4e097e
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Wed Feb 27 14:28:39 2013 +0100
Fixed#15901 -- Wrapped all PEP-249 exceptions.
commit 5476a5d93c19aa2f928c497d39ce6e33f52694e2
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Feb 26 17:26:52 2013 +0100
Added PEP 3134 exception chaining.
Thanks Jacob Kaplan-Moss for the suggestion.
commit 9365fad0a650328002fb424457d675a273c95802
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Feb 26 17:13:49 2013 +0100
Improved API for wrapping database errors.
Thanks Alex Gaynor for the proposal.
commit 1b463b765f2826f73a8d9266795cd5da4f8d5e9e
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Feb 26 15:00:39 2013 +0100
Removed redundant exception wrapping.
This is now taken care of by the cursor wrapper.
commit 524bc7345a724bf526bdd2dd1bcf5ede67d6bb5c
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Feb 26 14:55:10 2013 +0100
Wrapped database exceptions in the base backend.
This covers the most common PEP-249 APIs:
- Connection APIs: close(), commit(), rollback(), cursor()
- Cursor APIs: callproc(), close(), execute(), executemany(),
fetchone(), fetchmany(), fetchall(), nextset().
Fixed#19920.
commit a66746bb5f0839f35543222787fce3b6a0d0a3ea
Author: Aymeric Augustin <aymeric.augustin@m4x.org>
Date: Tue Feb 26 14:53:34 2013 +0100
Added a wrap_database_exception context manager and decorator.
It re-throws backend-specific exceptions using Django's common wrappers.
There were a couple of errors in ._dirty flag handling:
* It started as None, but was never reset to None.
* The _dirty flag was sometimes used to indicate if the connection
was inside transaction management, but this was not done
consistently. This also meant the flag had three separate values.
* The None value had a special meaning, causing for example inability
to commit() on new connection unless enter/leave tx management was
done.
* The _dirty was tracking "connection in transaction" state, but only
in managed transactions.
* Some tests never reset the transaction state of the used connection.
* And some additional less important changes.
This commit has some potential for regressions, but as the above list
shows, the current situation isn't perfect either.
