0.5 (2012-06-26)
----------------

Bug Fixes
~~~~~~~~~

- When a non-retryable exception was raised as the result of a call to
  ``transaction.manager.commit``, the exception was not reraised properly.
  Symptom: an unrecoverable exception such as ``Unsupported: Storing blobs in
  <somestorage> is not supported.`` would be swallowed inappropriately.

0.4 (2012-03-28)
----------------

Bug Fixes
~~~~~~~~~

- Work around failure to retry ConflictError properly at commit time by the
  ``transaction`` 1.2.0 package.  See
  https://mail.zope.org/pipermail/zodb-dev/2012-March/014603.html for
  details.

Testing
~~~~~~~

- No longer tested under Python 2.5 by ``tox.ini`` (and therefore no longer
  tested under 2.5 by the Pylons Jenkins server).  The package may still work
  under 2.5, but automated tests will no longer show breakage when it changes
  in ways that break 2.5 support.

- Squash test deprecation warnings under Python 3.2.

0.3 (2011-09-27)
----------------

Features
~~~~~~~~

- The transaction manager has been converted to a Pyramid 1.2 "tween"
  (instead of an event subscriber).  It will be slotted directly "below" the
  exception view handler, meaning it will have a chance to handle exceptions
  before they are turned into responses.  This means it's best to "raise
  HTTPFound(...)" instead of "return HTTPFound(...)" if you want an HTTP
  exception to abort the transaction.

- The transaction manager will now retry retryable exceptions (such as a ZODB
  conflict error) if ``tm.attempts`` is configured to be more than the
  default of ``1``.  See the ``Retrying`` section of the documentation.

- Python 3.2 compatibility (requires Pyramid 1.3dev+).

Backwards Incompatibilities
~~~~~~~~~~~~~~~~~~~~~~~~~~~

- Incompatible with Pyramid < 1.2a1.  Use ``pyramid_tm`` version 0.2 if you
  need compatibility with an older Pyramid installation.

- The ``default_commit_veto`` commit veto callback is no longer configured
  into the system by default.  Use ``tm.commit_veto =
  pyramid_tm.default_commit_veto`` in the deployment settings to add it.
  This is for parity with ``repoze.tm2``, which doesn't configure in a commit
  veto by default either.

- The ``default_commit_veto`` no longer checks for the presence of the
  ``X-Tm-Abort`` header when attempting to figure out whether the transaction
  should be aborted (although it still checks for the ``X-Tm`` header).  Use
  version 0.2 or a custom commit veto function if your application depends on
  the ``X-Tm-Abort`` header.

- A commit veto is now called with two arguments: ``request`` and
  ``response``.  The ``request`` is the webob request that caused the
  transaction manager to become active.  The ``response`` is the response
  returned by the Pyramid application.  This call signature is incompatible
  with older versions.  The call signature of a ``pyramid_tm`` 0.2 and older
  commit veto accepted three arguments: ``environ``, ``status``, and
  ``headers``.  If you're using a custom ``commit_veto`` function, you'll
  need to either convert your existing function to use the new calling
  convention or use a wrapper to make it compatible with the new calling
  convention.  Here's a simple wrapper function
  (``bwcompat_commit_veto_wrapper``) that will allow you to use your existing
  custom commit veto function::

     def bwcompat_commit_veto_wrapper(request, response):
         return my_custom_commit_veto(request.environ, response.status, 
                                      response.headerlist)

Deprecations
~~~~~~~~~~~~

- The ``pyramid_tm.commit_veto`` configuration setting is now canonically
  spelled as ``tm.commit_veto``.  The older spelling will continue to work,
  but may raise a deprecation error when used.

0.2 (2011-07-18)
----------------

- A new header ``X-Tm`` is now honored by the ``default_commit_veto`` commit
  veto hook. If this header exists in the headerlist, its value must be a
  string. If its value is ``commit``, the transaction will be committed
  regardless of the status code or the value of ``X-Tm-Abort``. If the value
  of the ``X-Tm`` header is ``abort`` (or any other string value except
  ``commit``), the transaction will be aborted, regardless of the status code
  or the value of ``X-Tm-Abort``.

0.1 (2011-02-23)
----------------

- Initial release, based on repoze.tm2