From be490633be4a6965145ec33ff0b11258ae688978 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Mon, 2 Dec 2013 17:28:32 +0100 Subject: asyncio: document network functions, and stream reader/writer --- Doc/library/asyncio.rst | 153 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 152 insertions(+), 1 deletion(-) diff --git a/Doc/library/asyncio.rst b/Doc/library/asyncio.rst index 1b8d701..801200a 100644 --- a/Doc/library/asyncio.rst +++ b/Doc/library/asyncio.rst @@ -94,7 +94,7 @@ Run an event loop .. method:: BaseEventLoop.run_until_complete(future) - Run until the :class:`Future` is done. + Run until the :class:`~concurrent.futures.Future` is done. If the argument is a coroutine, it is wrapped in a :class:`Task`. @@ -336,6 +336,58 @@ Run subprocesses asynchronously using the :mod:`subprocess` module. See the constructor of the :class:`subprocess.Popen` class for parameters. +Network functions +----------------- + +.. function:: open_connection(host=None, port=None, *, loop=None, limit=_DEFAULT_LIMIT, **kwds) + + A wrapper for create_connection() returning a (reader, writer) pair. + + The reader returned is a StreamReader instance; the writer is a + :class:`Transport`. + + The arguments are all the usual arguments to + :meth:`BaseEventLoop.create_connection` except *protocol_factory*; most + common are positional host and port, with various optional keyword arguments + following. + + Additional optional keyword arguments are *loop* (to set the event loop + instance to use) and *limit* (to set the buffer limit passed to the + StreamReader). + + (If you want to customize the :class:`StreamReader` and/or + :class:`StreamReaderProtocol` classes, just copy the code -- there's really + nothing special here except some convenience.) + + This function returns a :ref:`coroutine `. + +.. function:: start_server(client_connected_cb, host=None, port=None, *, loop=None, limit=_DEFAULT_LIMIT, **kwds) + + Start a socket server, call back for each client connected. + + The first parameter, *client_connected_cb*, takes two parameters: + *client_reader*, *client_writer*. *client_reader* is a + :class:`StreamReader` object, while *client_writer* is a + :class:`StreamWriter` object. This parameter can either be a plain callback + function or a :ref:`coroutine `; if it is a coroutine, it will be + automatically converted into a :class:`Task`. + + The rest of the arguments are all the usual arguments to + :meth:`~BaseEventLoop.create_server()` except *protocol_factory*; most + common are positional host and port, with various optional keyword arguments + following. The return value is the same as + :meth:`~BaseEventLoop.create_server()`. + + Additional optional keyword arguments are *loop* (to set the event loop + instance to use) and *limit* (to set the buffer limit passed to the + :class:`StreamReader`). + + The return value is the same as :meth:`~BaseEventLoop.create_server()`, i.e. + a Server object which can be used to stop the service. + + This function returns a :ref:`coroutine `. + + .. _protocol: Protocols @@ -843,6 +895,105 @@ call them yourself, unless you are implementing a transport. are interested. +Stream reader and writer +------------------------ + +.. class:: StreamWriter(transport, protocol, reader, loop) + + Wraps a Transport. + + This exposes :meth:`write`, :meth:`writelines`, :meth:`can_write_eof()`, :meth:`write_eof`, :meth:`get_extra_info` and + :meth:`close`. It adds :meth:`drain` which returns an optional :class:`~concurrent.futures.Future` on which you can + wait for flow control. It also adds a transport attribute which references + the :class:`Transport` directly. + + .. attribute:: transport + + Transport. + + .. method:: write(data) + + XXX + + .. method:: writelines(data) + + XXX + + .. method:: write_eof() + + XXX + + .. method:: can_write_eof() + + XXX + + .. method:: close() + + XXX + + .. method:: get_extra_info(name, default=None) + + XXX + + .. method:: drain() + + This method has an unusual return value. + + The intended use is to write:: + + w.write(data) + yield from w.drain() + + When there's nothing to wait for, :meth:`drain()` returns ``()``, and the + yield-from continues immediately. When the transport buffer is full (the + protocol is paused), :meth:`drain` creates and returns a + :class:`~concurrent.futures.Future` and the yield-from will block until + that Future is completed, which will happen when the buffer is + (partially) drained and the protocol is resumed. + + +.. class:: StreamReader(limit=_DEFAULT_LIMIT, loop=None) + + .. method:: exception() + + Get the exception. + + .. method:: set_exception(exc) + + Set the exception. + + .. method:: set_transport(transport) + + Set the transport. + + .. method:: feed_eof() + + XXX + + .. method:: feed_data(data) + + XXX + + .. method:: read(n=-1) + + XXX + + This method returns a :ref:`coroutine `. + + .. method:: readexactly(n) + + XXX + + This method returns a :ref:`coroutine `. + + .. method:: readline() + + XXX + + This method returns a :ref:`coroutine `. + + + .. _coroutine: Coroutines -- cgit v0.12