magic-removal: Typo corrections in transaction code and docs
git-svn-id: http://code.djangoproject.com/svn/django/branches/magic-removal@2462 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
parent
27bb553ba0
commit
8c8afa22c0
|
@ -18,8 +18,8 @@ from django.conf import settings
|
|||
|
||||
class TransactionManagementError(Exception):
|
||||
"""
|
||||
This is the exception that is thrown when
|
||||
something bad happens with transaction management.
|
||||
This exception is thrown when something bad happens with transaction
|
||||
management.
|
||||
"""
|
||||
pass
|
||||
|
||||
|
@ -39,7 +39,7 @@ def enter_transaction_management():
|
|||
managed as a stack.
|
||||
|
||||
The state and dirty flag are carried over from the surrounding block or
|
||||
from the settings, if there is no surrounding block (dirty is allways false
|
||||
from the settings, if there is no surrounding block (dirty is always false
|
||||
when no current block is running).
|
||||
"""
|
||||
thread_ident = thread.get_ident()
|
||||
|
@ -55,7 +55,7 @@ def leave_transaction_management():
|
|||
"""
|
||||
Leaves transaction management for a running thread. A dirty flag is carried
|
||||
over to the surrounding block, as a commit will commit all changes, even
|
||||
those from outside (commits are on connection level).
|
||||
those from outside. (Commits are on connection level.)
|
||||
"""
|
||||
thread_ident = thread.get_ident()
|
||||
if state.has_key(thread_ident) and state[thread_ident]:
|
||||
|
@ -63,14 +63,14 @@ def leave_transaction_management():
|
|||
else:
|
||||
raise TransactionManagementError("This code isn't under transaction management")
|
||||
if dirty.get(thread_ident, False):
|
||||
# I fixed it for you this time, but don't do it again!
|
||||
rollback()
|
||||
raise TransactionManagementError("Transaction managed block ended with pending COMMIT/ROLLBACK")
|
||||
dirty[thread_ident] = False
|
||||
|
||||
def is_dirty():
|
||||
"""
|
||||
Checks if the current transaction requires a commit for changes to happen.
|
||||
Returns True if the current transaction requires a commit for changes to
|
||||
happen.
|
||||
"""
|
||||
return dirty.get(thread.get_ident(), False)
|
||||
|
||||
|
@ -89,8 +89,8 @@ def set_dirty():
|
|||
def set_clean():
|
||||
"""
|
||||
Resets a dirty flag for the current thread and code streak. This can be used
|
||||
to decide in a managed block of code to decide whether there should happen a
|
||||
commit or rollback.
|
||||
to decide in a managed block of code to decide whether a commit or rollback
|
||||
should happen.
|
||||
"""
|
||||
thread_ident = thread.get_ident()
|
||||
if dirty.has_key(thread_ident):
|
||||
|
@ -110,7 +110,7 @@ def is_managed():
|
|||
|
||||
def managed(flag=True):
|
||||
"""
|
||||
Puts the transaction manager into a manual state - managed transactions have
|
||||
Puts the transaction manager into a manual state: managed transactions have
|
||||
to be committed explicitely by the user. If you switch off transaction
|
||||
management and there is a pending commit/rollback, the data will be
|
||||
commited.
|
||||
|
@ -163,11 +163,10 @@ def rollback():
|
|||
|
||||
def autocommit(func):
|
||||
"""
|
||||
Decorator that activates commit on save. This is Django's default behavour;
|
||||
Decorator that activates commit on save. This is Django's default behavior;
|
||||
this decorator is useful if you globally activated transaction management in
|
||||
your settings file and want the default behaviour in some view functions.
|
||||
your settings file and want the default behavior in some view functions.
|
||||
"""
|
||||
|
||||
def _autocommit(*args, **kw):
|
||||
try:
|
||||
enter_transaction_management()
|
||||
|
@ -175,17 +174,15 @@ def autocommit(func):
|
|||
return func(*args, **kw)
|
||||
finally:
|
||||
leave_transaction_management()
|
||||
|
||||
return _autocommit
|
||||
|
||||
def commit_on_success(func):
|
||||
"""
|
||||
This decorator activates commit on response. This way if the viewfunction
|
||||
runs successfully, a commit is made, if the viewfunc produces an exception,
|
||||
This decorator activates commit on response. This way, if the view function
|
||||
runs successfully, a commit is made; if the viewfunc produces an exception,
|
||||
a rollback is made. This is one of the most common ways to do transaction
|
||||
control in web apps.
|
||||
"""
|
||||
|
||||
def _commit_on_success(*args, **kw):
|
||||
try:
|
||||
enter_transaction_management()
|
||||
|
@ -202,16 +199,15 @@ def commit_on_success(func):
|
|||
return res
|
||||
finally:
|
||||
leave_transaction_management()
|
||||
|
||||
return _commit_on_success
|
||||
|
||||
def commit_manually(func):
|
||||
"""
|
||||
Decorator that activates manual transaction control. It just disables
|
||||
automatic transaction control and doesn't do any commit/rollback of it's own
|
||||
- it's up to the user to call the commit and rollback functions themselves.
|
||||
automatic transaction control and doesn't do any commit/rollback of its
|
||||
own -- it's up to the user to call the commit and rollback functions
|
||||
themselves.
|
||||
"""
|
||||
|
||||
def _commit_manually(*args, **kw):
|
||||
try:
|
||||
enter_transaction_management()
|
||||
|
@ -221,5 +217,3 @@ def commit_manually(func):
|
|||
leave_transaction_management()
|
||||
|
||||
return _commit_manually
|
||||
|
||||
|
||||
|
|
|
@ -5,10 +5,9 @@ class TransactionMiddleware:
|
|||
"""
|
||||
Transaction middleware. If this is enabled, each view function will be run
|
||||
with commit_on_response activated - that way a save() doesn't do a direct
|
||||
commit, the commit is done when a successfull response is created. If an
|
||||
commit, the commit is done when a successful response is created. If an
|
||||
exception happens, the database is rolled back.
|
||||
"""
|
||||
|
||||
def process_request(self, request):
|
||||
"""Enters transaction management"""
|
||||
transaction.enter_transaction_management()
|
||||
|
|
|
@ -39,17 +39,17 @@ only for the view functions called, but for all middleware modules that come
|
|||
after it. So if you use the session middleware after the transaction middleware,
|
||||
session creation will be part of the transaction.
|
||||
|
||||
The cache middleware isn't affected as it uses it's own database cursor (that is
|
||||
mapped to it's own database connection internally) and only the database based
|
||||
cache is affected.
|
||||
The cache middleware isn't affected, as it uses its own database cursor (which
|
||||
is mapped to its own database connection internally), and only the
|
||||
database-based cache is affected.
|
||||
|
||||
Controlling transaction management in views
|
||||
===========================================
|
||||
|
||||
For many people, implicit request-based transactions will work wonderfully.
|
||||
However, if you need to control the way that transactions are managed,
|
||||
there are a set of decorators that you can apply to a function to change
|
||||
the way transactions are handled.
|
||||
you can use decorators that you can apply to a function to change the way
|
||||
transactions are handled.
|
||||
|
||||
.. note::
|
||||
|
||||
|
@ -69,8 +69,8 @@ the decorator like this::
|
|||
def viewfunc(request):
|
||||
....
|
||||
|
||||
Within ``viewfunc`` transactions will be comitted as soon as you call
|
||||
``model.save()``, ``model.delete()``, or any similar function that writes to the
|
||||
Within ``viewfunc`` transactions will be committed as soon as you call
|
||||
``model.save()``, ``model.delete()``, or any other function that writes to the
|
||||
database.
|
||||
|
||||
``commit_on_success``
|
||||
|
@ -85,7 +85,7 @@ all the work done in a function::
|
|||
def viewfunc(request):
|
||||
....
|
||||
|
||||
If the function returns successfully then all work done will be committed. If an
|
||||
If the function returns successfully, then all work done will be committed. If an
|
||||
exception is raised beyond the function, however, the transaction will be rolled
|
||||
back.
|
||||
|
||||
|
@ -93,10 +93,12 @@ back.
|
|||
-------------------
|
||||
|
||||
Sometimes you need full control over your transactions. In that case, you can use the
|
||||
``commit_manually`` decorator which will make you run your own transaction management.
|
||||
``commit_manually`` decorator, which tells Django you'll be managing the transaction
|
||||
on your own.
|
||||
|
||||
If you don't commit or rollback and did change data (so that the current transaction
|
||||
is marked as dirty), you will get a ``TransactionManagementError`` exception saying so.
|
||||
If you don't commit or rollback and did change data (so that the current
|
||||
transaction is marked as dirty), you'll get a ``TransactionManagementError``
|
||||
exception.
|
||||
|
||||
Manual transaction management looks like::
|
||||
|
||||
|
@ -117,7 +119,7 @@ Manual transaction management looks like::
|
|||
else:
|
||||
transaction.commit()
|
||||
|
||||
..admonition:: An important note to users of earlier django releases:
|
||||
..admonition:: An important note to users of earlier Django releases:
|
||||
|
||||
The database ``connection.commit`` and ``connection.rollback`` functions
|
||||
(also called ``db.commit`` and ``db.rollback`` in 0.91 and earlier), no
|
||||
|
@ -128,7 +130,7 @@ How to globally deactivate transaction management
|
|||
=================================================
|
||||
|
||||
Control freaks can totally disable all transaction management by setting
|
||||
``DISABLE_TRANSACTION_MANAGEMENT`` to ``True`` in your settings file.
|
||||
``DISABLE_TRANSACTION_MANAGEMENT`` to ``True`` in the Django settings file.
|
||||
|
||||
If you do this, there will be no management whatsoever. The middleware will no
|
||||
longer implicitly commit transactions, and you'll need to roll management
|
||||
|
@ -136,6 +138,6 @@ yourself. This even will require you to commit changes done by middleware
|
|||
somewhere else.
|
||||
|
||||
Thus, this is best used in situations where you want to run your own transaction
|
||||
controlling middleware or do something really strange. In almost all situations
|
||||
controlling middleware or do something really strange. In almost all situations,
|
||||
you'll be better off using the default behavior or the transaction middleware
|
||||
and only modify selected functions as needed.
|
Loading…
Reference in New Issue