app/django/middleware/transaction.py
author Sverre Rabbelier <srabbelier@gmail.com>
Sat, 22 Nov 2008 14:53:23 +0000
changeset 555 3cdfb42d941b
parent 54 03e267d67478
permissions -rw-r--r--
Split the list view code up in three pieces 1. getListContents which returns the required contents dictionary 2. _list which returns the response for a specified list of contents 3. list which constructs just one content dict and passes it to _list This way it is easier to do step 1 and 2 in other code than list(), which makes it possible to display multiple list pages (by calling getListContents multiple times and passing the result to _list).

from django.db import transaction

class TransactionMiddleware(object):
    """
    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 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()
        transaction.managed(True)

    def process_exception(self, request, exception):
        """Rolls back the database and leaves transaction management"""
        if transaction.is_dirty():
            transaction.rollback()
        transaction.leave_transaction_management()

    def process_response(self, request, response):
        """Commits and leaves transaction management."""
        if transaction.is_managed():
            if transaction.is_dirty():
                transaction.commit()
            transaction.leave_transaction_management()
        return response