app/django/middleware/transaction.py
author Todd Larsen <tlarsen@google.com>
Wed, 15 Oct 2008 17:10:27 +0000
changeset 339 b9be44e09530
parent 54 03e267d67478
permissions -rw-r--r--
Define the Models for implementing Quizzes (collections of Questions) and their Responses (collections of Answers to those Questions). These Models would form the basis of storage for such items as: Terms of Service (Quiz) Question ("I agree...") Response -> Answer (answer to "I agree..." confirmation) solution ("Yes" Answer to the "I agree..." Question) Mentor and Student surveys (Quiz) Questions (including "Pay this student?") Response -> Answers solution ("Yes" Answer to the "Pay this student?" Question) Organization applications Student Proposal review, comment, and scoring system GHOP task tracking (a specific task list item would be a Quiz) Patch by: Todd Larsen Review by: Pawel Solyga, Sverre Rabbelier, Chen Lunpeng Review URL: http://codereviews.googleopensourceprograms.com/1403

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