Thanks Anssi for haggling until I implemented this.
This change alleviates the need for atomic_if_autocommit. When
autocommit is disabled for a database, atomic will simply create and
release savepoints, and not commit anything. This honors the contract of
not doing any transaction management.
This change also makes the hack to allow using atomic within the legacy
transaction management redundant.
None of the above will work with SQLite, because of a flaw in the design
of the sqlite3 library. This is a known limitation that cannot be lifted
without unacceptable side effects eg. triggering arbitrary commits.
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.
Since "unless managed" now means "if database-level autocommit",
committing or rolling back doesn't have any effect.
Restored transactional integrity in a few places that relied on
automatically-started transactions with a transitory API.
enter_transaction_management() was nearly always followed by managed().
In three places it wasn't, but they will all be refactored eventually.
The "forced" keyword argument avoids introducing behavior changes until
then.
This is mostly backwards-compatible, except, of course, for managed
itself. There's a minor difference in _enter_transaction_management:
the top self.transaction_state now contains the new 'managed' state
rather than the previous one. Django doesn't access
self.transaction_state in _enter_transaction_management.
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.