Fixed bug that caused KeyError in _commit_all_savepoints #34
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…er._commit_savepoint - issue #30 on Github (#69 on Bitbucket) This patch is fixing cause of the problem, not hiding it as pull requests #26 and #30. To reproduce cause of the problem you should: 1) Enable QueryCacheMiddleware 2) Work in unmanaged transaction state (it means autocommit mode, i.e. without 'django.middleware.transaction.TransactionMiddleware' and not within 'transaction.enter_transaction_management()' block) 3) Create a savepoint and then try to save some object (it is done by 'django.db.models.query.QuerySet#get_or_create' or by 'django.contrib.sessions.backends.db.SessionStore#save') The essence of the problem is the fact that Django ORM widely uses a 'django/db/transaction.py#commit_unless_managed' (which is unpatched by Johny Cache) function instead of 'django/db/transaction.py#commit_unless_managed' (which is patched by Johny Cache). So, when we working in unmanaged transaction state Johny Cache will still register savepoints upon creation but will be unable to handle commits and rollbacks that wast performed by 'unless_managed' functions. Since Django is using dumb algorithm for savepoint names generation (they reuse same names within thread once they were commited) it will lead to a situation when Johny Cache will register several savepoints with same name within one transaction and fail when it will try to commit or rollback them. Proposed solution adds patching to 'django/db/transaction.py#commit_unless_managed' and 'django/db/transaction.py#rollback_unless_managed' functions in the same way as it was done for 'django/db/transaction.py#commit' and 'django/db/transaction.py#rollback' functions with one difference - additional check whether current transaction is unmanaged.
jmoiron
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Oct 4, 2013
Fixed bug that caused KeyError in _commit_all_savepoints
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If you could contribute a test case that checks for this behavior that would be amazing, but otherwise jself or I will get around to it when we have the time. Thanks for the PR! |
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Ok, I'll add a tests for this fix and for my previous fix in few days and create a new pull request. |
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Fixed bug that caused KeyError in johnny.transaction.TransactionManager._commit_all_savepoints - issues #26 and #30 on Github (#69 on Bitbucket)
This patch is fixing cause of the problem, not hiding it as pull requests #26 and #30.
To reproduce cause of the problem you should:
The essence of the problem is the fact that Django ORM widely uses a django/db/transaction.py#commit_unless_managed (which is unpatched by Johny Cache) function instead of django/db/transaction.py#commit (which is patched by Johny Cache). So, when we working in unmanaged transaction state Johny Cache will still register savepoints upon creation but will be unable to handle commits and rollbacks that wast performed by 'unless_managed' functions. Since Django is using dumb algorithm for savepoint names generation (they reuse same names within thread once they were commited) it will lead to a situation when Johny Cache will register several savepoints with same name within one transaction and fail when it will try to commit or rollback them.
Proposed solution adds patching to django/db/transaction.py#commit_unless_managed and django/db/transaction.py#rollback_unless_managed functions in the same way as it was done for django/db/transaction.py#commit and django/db/transaction.py#rollback functions with one difference - additional check whether current transaction is unmanaged.