app/django/middleware/transaction.py
author Sverre Rabbelier <srabbelier@gmail.com>
Mon, 03 Nov 2008 19:47:02 +0000
changeset 439 0658c3c9a9dc
parent 54 03e267d67478
permissions -rw-r--r--
Minor fixes needed for generic key name We no longer try to retreive an entity when there are unset fields. This sort of makes 'getIfFields' obsolete, since we check if fields now anyway. This is needed because getKeyFieldsFromDict expects the fields to be set. Also a minor fix in a Django template so that the generic 'edit' page has a working delete button again.

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