docs/releases/v2.4.0.rst
General
* Fixed Python 3 bugs in `tornado.auth`, `tornado.locale`, and `tornado.wsgi`.
HTTP clients
max_simultaneous_connections argument from tornado.httpclient
(both implementations). This argument hasn't been useful for some time
(if you were using it you probably want max_clients instead)tornado.simple_httpclient now accepts and ignores HTTP 1xx status
responses.tornado.ioloop and tornado.iostream
* Fixed a bug introduced in 2.3 that would cause `.IOStream` close callbacks
to not run if there were pending reads.
* Improved error handling in `.SSLIOStream` and SSL-enabled `.TCPServer`.
* ``SSLIOStream.get_ssl_certificate`` now has a ``binary_form`` argument
which is passed to ``SSLSocket.getpeercert``.
* ``SSLIOStream.write`` can now be called while the connection is in progress,
same as non-SSL `.IOStream` (but be careful not to send sensitive data until
the connection has completed and the certificate has been verified).
* `.IOLoop.add_handler` cannot be called more than once with the same file
descriptor. This was always true for ``epoll``, but now the other
implementations enforce it too.
* On Windows, `.TCPServer` uses ``SO_EXCLUSIVEADDRUSER`` instead of ``SO_REUSEADDR``.
`tornado.template`
~~~~~~~~~~~~~~~~~~
* ``{% break %}`` and ``{% continue %}`` can now be used looping constructs
in templates.
* It is no longer an error for an if/else/for/etc block in a template to
have an empty body.
`tornado.testing`
~~~~~~~~~~~~~~~~~
* New class `tornado.testing.AsyncHTTPSTestCase` is like `.AsyncHTTPTestCase`.
but enables SSL for the testing server (by default using a self-signed
testing certificate).
* `tornado.testing.main` now accepts additional keyword arguments and forwards
them to `unittest.main`.
`tornado.web`
~~~~~~~~~~~~~
* New method `.RequestHandler.get_template_namespace` can be overridden to
add additional variables without modifying keyword arguments to
``render_string``.
* `.RequestHandler.add_header` now works with ``WSGIApplication``.
* `.RequestHandler.get_secure_cookie` now handles a potential error case.
* ``RequestHandler.__init__`` now calls ``super().__init__`` to ensure that
all constructors are called when multiple inheritance is used.
* Docs have been updated with a description of all available
:py:attr:`Application settings <tornado.web.Application.settings>`
Other modules
~~~~~~~~~~~~~
* `.OAuthMixin` now accepts ``"oob"`` as a ``callback_uri``.
* `.OpenIdMixin` now also returns the ``claimed_id`` field for the user.
* `tornado.platform.twisted` shutdown sequence is now more compatible.
* The logging configuration used in `tornado.options` is now more tolerant
of non-ascii byte strings.