yet-another-io-channels-library 0.1.1

Simple IO channels library

Channels

Simple wrapper around file objects and sockets that provides uniform interface to both.

Example:

pipe_chan = PipeChannel(sys.stdin.fileno(), sys.stdout.fileno())
sock_chan = SocketChannel(socket.create_connection(('127.0.0.1', 8080))

Classes

Channel

Channel is the base class for different channels. Every channel implements the following methods:

read(self)

Performs a non-blocking read and returns any bytes available. Raises EndpointClosedException if the channel is closed.

write(self, *data)

Writes chunks of bytes to the channel. Raises EndpointClosedException.

close(self)

Closes the channel and frees up the resources.

get_fd(self)

Returns a file descriptor number that can be used for poll or epoll for reading. Raises NotImplementedError if (custom) channel doesn't support reading.

The following channel classes are implemented:

PipeChannel

PipeChannel(faucet=None, sink=None)

faucet should be a file descriptor open for reading. sink should be a file descriptor open for writing. If both are provided, the channel is bi-directional. Sets faucet to non-blocking mode.

SocketChannel

SocketChannel(sock)

Wraps a socket for non-blocking IO.

LineChannel

LineChannel(channel)

Accepts another channel. read() returns one line at time or b'' if no full line is available. If underlying channel is closed, read() will keep returning lines until everything is returned (last line might not be ending with b'\n').

TestChannel

(in package channels.testing)

Provides put and get methods to to feed data to read and fetch "written" data respectively.

Poller

Poller is a wrapper for select.poll that also supports accepting and keeping track of TCP/Unix clients.

register(self, channel)

Registers the channel for polling.

add_server(self, sock)

Registers a server socket. Poller will accept incoming connections and automatically register clients.

unregister(self, channel)

Removes a registered channel.

close_all(self)

Closes all registered channels and servers.

poll(self, timeout=None)

Performs a single call to select.poll(). timeout is the number of seconds for polling or None for infinite polling. Return value is a list of pairs in format of (data, channel) for channels and ((addr, client_channel), sock) for server sockets. addr depends on socket type.