app/django/middleware/transaction.py
author Todd Larsen <tlarsen@google.com>
Thu, 20 Nov 2008 17:54:51 +0000
changeset 510 6cd4f44891e5
parent 54 03e267d67478
permissions -rw-r--r--
id() is a built-in function in Python, so rename the property to link_id. Add a scope_path StringProperty to cache the string representation of the transitive closure of the nested scopes of an entity. Patch by: Todd Larsen

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