Async Networking

# Create a non-blocking socket server that logs data and closes connections.

import functools
import socket

from asyncdef.engine.core import Engine
from asyncdef.engine.processors.selector import Selector

# Generate a non-blocking socket listener.
sock = socket.socket()
sock.setblocking(0)
sock.bind(('localhost', 9898))
sock.listen()


def handle_data(selector, conn):
    """Triggered on data waiting for read."""
    data = conn.recv(4096)
    print('Got data {}.'.format(data))
    selector.remove_reader(conn)
    conn.close()


def handle_connection(selector, listening_socket):
    """Triggered on new incoming connection."""
    conn, addr = listening_socket.accept()
    conn.setblocking(0)
    selector.add_reader(
        conn,
        functools.partial(handle_data, selector),
    )

# Create an instance of the selector and event loop.
selector = Selector()
loop = Engine(selector)

# Set up the socket polling.
selector.add_reader(sock, functools.partial(handle_connection, selector))

# Start the event loop.
loop.start()

Time Scheduling

# Schedule a function to run in five seconds.
import functools

from asyncdef.engine.core import Engine
from asyncdef.engine.processors.time import Time


def print_and_stop(loop):
    print("Stopping the loop.")
    loop.stop()

time = Time()
loop = Engine(time)
handle = loop.defer_for(5, functools.partial(print_and_stop, loop))

loop.start()

Coroutine Management

import functools
from concurrent.futures import Future

from asyncdef.engine.core import Engine
from asyncdef.engine.processors.coroutine import Coroutine
from asyncdef.engine.processors.time import Time


class AwaitableFuture(Future):

    """An awaitable version of the standard lib Future."""

    def __await__(self):
        """Return self until resolved."""
        while self._state != 'FINISHED':

            yield self

        return self.result()


async def wait_for_future(loop, future):
    value = await future
    print('Got value {}. Stopping the loop.'.format(value))
    loop.stop()


def resolve_future(future):
    print('Resolving future.')
    future.set_result(True)

time = Time()
coromgr = Coroutine()
loop = Engine(coromgr, time)

future = AwaitableFuture()
time.defer_for(5, functools.partial(resolve_future, future))
handle = coromgr.add(wait_for_future(loop, future))

loop.start()

Style

As long as the code passes the PEP8 and PyFlakes gates then the style is acceptable.

Docs

The PEP257 gate will check that all public methods have docstrings. If you’re adding something new, like a helper function, try out the napoleon style of docstrings.

Tests

Make sure the patch passes all the tests. If you’re adding a new feature don’t forget to throw in a test or two. If you’re fixing a bug then definitely add at least one test to prevent regressions.