``tornado.platform.twisted`` --- Twisted 与 Tornado 之间的桥梁
========================================================================

.. module:: tornado.platform.twisted

该模块使得 为 Twisted 所编写的应用和类库可以在 Tornado 中运行，其方法有两种，
取决于你想要使用哪个底层事件循环。

该模块已通过 Twisted 11.0.0 及以后版本测试。

Twisted on Tornado
------------------

.. py:class:: TornadoReactor

    ``TornadoReactor`` implements the Twisted reactor interface on top of
    the Tornado IOLoop.  To use it, simply call ``install`` at the beginning
    of the application::

        import tornado.platform.twisted
        tornado.platform.twisted.install()
        from twisted.internet import reactor

    When the app is ready to start, call ``IOLoop.instance().start()``
    instead of ``reactor.run()``.

    It is also possible to create a non-global reactor by calling
    ``tornado.platform.twisted.TornadoReactor(io_loop)``.  However, if
    the `.IOLoop` and reactor are to be short-lived (such as those used in
    unit tests), additional cleanup may be required.  Specifically, it is
    recommended to call::

        reactor.fireSystemEvent('shutdown')
        reactor.disconnectAll()

    before closing the `.IOLoop`.

Tornado on Twisted
------------------

.. py:class:: TwistedIOLoop

    ``TwistedIOLoop`` implements the Tornado IOLoop interface on top
    of the Twisted reactor.  Recommended usage::

        from tornado.platform.twisted import TwistedIOLoop
        from twisted.internet import reactor
        TwistedIOLoop().install()
        # Set up your tornado application as usual using `IOLoop.instance`
        reactor.run()

    ``TwistedIOLoop`` always uses the global Twisted reactor.

Twisted DNS resolver
--------------------

.. py:class:: TwistedResolver

    This is a non-blocking and non-threaded resolver.  It is
    recommended only when threads cannot be used, since it has
    limitations compared to the standard ``getaddrinfo``-based
    `~tornado.netutil.Resolver` and
    `~tornado.netutil.ThreadedResolver`.  Specifically, it returns at
    most one result, and arguments other than ``host`` and ``family``
    are ignored.  It may fail to resolve when ``family`` is not
    ``socket.AF_UNSPEC``.

    Requires Twisted 12.1 or newer.