asyncio: Add support for UNIX Domain Sockets.

Lib/asyncio/base_events.py

@@ -407,6 +407,13 @@ class BaseEventLoop(events.AbstractEventLoop):
 
         sock.setblocking(False)
 
+        transport, protocol = yield from self._create_connection_transport(
+            sock, protocol_factory, ssl, server_hostname)
+        return transport, protocol
+
+    @tasks.coroutine
+    def _create_connection_transport(self, sock, protocol_factory, ssl,
+                                     server_hostname):
         protocol = protocol_factory()
         waiter = futures.Future(loop=self)
         if ssl:

Lib/asyncio/events.py

@@ -220,6 +220,32 @@ class AbstractEventLoop:
         """
         raise NotImplementedError
 
+    def create_unix_connection(self, protocol_factory, path, *,
+                               ssl=None, sock=None,
+                               server_hostname=None):
+        raise NotImplementedError
+
+    def create_unix_server(self, protocol_factory, path, *,
+                           sock=None, backlog=100, ssl=None):
+        """A coroutine which creates a UNIX Domain Socket server.
+
+        The return valud is a Server object, which can be used to stop
+        the service.
+
+        path is a str, representing a file systsem path to bind the
+        server socket to.
+
+        sock can optionally be specified in order to use a preexisting
+        socket object.
+
+        backlog is the maximum number of queued connections passed to
+        listen() (defaults to 100).
+
+        ssl can be set to an SSLContext to enable SSL over the
+        accepted connections.
+        """
+        raise NotImplementedError
+
     def create_datagram_endpoint(self, protocol_factory,
                                  local_addr=None, remote_addr=None, *,
                                  family=0, proto=0, flags=0):

Lib/asyncio/streams.py

 """Stream-related things."""
 
 __all__ = ['StreamReader', 'StreamWriter', 'StreamReaderProtocol',
-           'open_connection', 'start_server', 'IncompleteReadError',
+           'open_connection', 'start_server',
+           'open_unix_connection', 'start_unix_server',
+           'IncompleteReadError',
            ]
 
+import socket
+
 from . import events
 from . import futures
 from . import protocols
@@ -93,6 +97,39 @@ def start_server(client_connected_cb, host=None, port=None, *,
     return (yield from loop.create_server(factory, host, port, **kwds))
 
 
+if hasattr(socket, 'AF_UNIX'):
+    # UNIX Domain Sockets are supported on this platform
+
+    @tasks.coroutine
+    def open_unix_connection(path=None, *,
+                             loop=None, limit=_DEFAULT_LIMIT, **kwds):
+        """Similar to `open_connection` but works with UNIX Domain Sockets."""
+        if loop is None:
+            loop = events.get_event_loop()
+        reader = StreamReader(limit=limit, loop=loop)
+        protocol = StreamReaderProtocol(reader, loop=loop)
+        transport, _ = yield from loop.create_unix_connection(
+            lambda: protocol, path, **kwds)
+        writer = StreamWriter(transport, protocol, reader, loop)
+        return reader, writer
+
+
+    @tasks.coroutine
+    def start_unix_server(client_connected_cb, path=None, *,
+                          loop=None, limit=_DEFAULT_LIMIT, **kwds):
+        """Similar to `start_server` but works with UNIX Domain Sockets."""
+        if loop is None:
+            loop = events.get_event_loop()
+
+        def factory():
+            reader = StreamReader(limit=limit, loop=loop)
+            protocol = StreamReaderProtocol(reader, client_connected_cb,
+                                            loop=loop)
+            return protocol
+
+        return (yield from loop.create_unix_server(factory, path, **kwds))
+
+
 class FlowControlMixin(protocols.Protocol):
     """Reusable flow control logic for StreamWriter.drain().
 

Lib/asyncio/test_utils.py

@@ -4,12 +4,18 @@ import collections
 import contextlib
 import io
 import os
+import socket
+import socketserver
 import sys
+import tempfile
 import threading
 import time
 import unittest
 import unittest.mock
+
+from http.server import HTTPServer
 from wsgiref.simple_server import make_server, WSGIRequestHandler, WSGIServer
+
 try:
     import ssl
 except ImportError:  # pragma: no cover
@@ -70,42 +76,51 @@ def run_once(loop):
     loop.run_forever()
 
 
-@contextlib.contextmanager
-def run_test_server(*, host='127.0.0.1', port=0, use_ssl=False):
+class SilentWSGIRequestHandler(WSGIRequestHandler):
 
-    class SilentWSGIRequestHandler(WSGIRequestHandler):
-        def get_stderr(self):
-            return io.StringIO()
+    def get_stderr(self):
+        return io.StringIO()
 
-        def log_message(self, format, *args):
-            pass
+    def log_message(self, format, *args):
+        pass
 
-    class SilentWSGIServer(WSGIServer):
-        def handle_error(self, request, client_address):
+
+class SilentWSGIServer(WSGIServer):
+
+    def handle_error(self, request, client_address):
+        pass
+
+
+class SSLWSGIServerMixin:
+
+    def finish_request(self, request, client_address):
+        # The relative location of our test directory (which
+        # contains the ssl key and certificate files) differs
+        # between the stdlib and stand-alone asyncio.
+        # Prefer our own if we can find it.
+        here = os.path.join(os.path.dirname(__file__), '..', 'tests')
+        if not os.path.isdir(here):
+            here = os.path.join(os.path.dirname(os.__file__),
+                                'test', 'test_asyncio')
+        keyfile = os.path.join(here, 'ssl_key.pem')
+        certfile = os.path.join(here, 'ssl_cert.pem')
+        ssock = ssl.wrap_socket(request,
+                                keyfile=keyfile,
+                                certfile=certfile,
+                                server_side=True)
+        try:
+            self.RequestHandlerClass(ssock, client_address, self)
+            ssock.close()
+        except OSError:
+            # maybe socket has been closed by peer
             pass
 
-    class SSLWSGIServer(SilentWSGIServer):
-        def finish_request(self, request, client_address):
-            # The relative location of our test directory (which
-            # contains the ssl key and certificate files) differs
-            # between the stdlib and stand-alone asyncio.
-            # Prefer our own if we can find it.
-            here = os.path.join(os.path.dirname(__file__), '..', 'tests')
-            if not os.path.isdir(here):
-                here = os.path.join(os.path.dirname(os.__file__),
-                                    'test', 'test_asyncio')
-            keyfile = os.path.join(here, 'ssl_key.pem')
-            certfile = os.path.join(here, 'ssl_cert.pem')
-            ssock = ssl.wrap_socket(request,
-                                    keyfile=keyfile,
-                                    certfile=certfile,
-                                    server_side=True)
-            try:
-                self.RequestHandlerClass(ssock, client_address, self)
-                ssock.close()
-            except OSError:
-                # maybe socket has been closed by peer
-                pass
+
+class SSLWSGIServer(SSLWSGIServerMixin, SilentWSGIServer):
+    pass
+
+
+def _run_test_server(*, address, use_ssl=False, server_cls, server_ssl_cls):
 
     def app(environ, start_response):
         status = '200 OK'
@@ -115,9 +130,9 @@ def run_test_server(*, host='127.0.0.1', port=0, use_ssl=False):
 
     # Run the test WSGI server in a separate thread in order not to
     # interfere with event handling in the main thread
-    server_class = SSLWSGIServer if use_ssl else SilentWSGIServer
-    httpd = make_server(host, port, app,
-                        server_class, SilentWSGIRequestHandler)
+    server_class = server_ssl_cls if use_ssl else server_cls
+    httpd = server_class(address, SilentWSGIRequestHandler)
+    httpd.set_app(app)
     httpd.address = httpd.server_address
     server_thread = threading.Thread(target=httpd.serve_forever)
     server_thread.start()
@@ -129,6 +144,75 @@ def run_test_server(*, host='127.0.0.1', port=0, use_ssl=False):
         server_thread.join()
 
 
+if hasattr(socket, 'AF_UNIX'):
+
+    class UnixHTTPServer(socketserver.UnixStreamServer, HTTPServer):
+
+        def server_bind(self):
+            socketserver.UnixStreamServer.server_bind(self)
+            self.server_name = '127.0.0.1'
+            self.server_port = 80
+
+
+    class UnixWSGIServer(UnixHTTPServer, WSGIServer):
+
+        def server_bind(self):
+            UnixHTTPServer.server_bind(self)
+            self.setup_environ()
+
+        def get_request(self):
+            request, client_addr = super().get_request()
+            # Code in the stdlib expects that get_request
+            # will return a socket and a tuple (host, port).
+            # However, this isn't true for UNIX sockets,
+            # as the second return value will be a path;
+            # hence we return some fake data sufficient
+            # to get the tests going
+            return request, ('127.0.0.1', '')
+
+
+    class SilentUnixWSGIServer(UnixWSGIServer):
+
+        def handle_error(self, request, client_address):
+            pass
+
+
+    class UnixSSLWSGIServer(SSLWSGIServerMixin, SilentUnixWSGIServer):
+        pass
+
+
+    def gen_unix_socket_path():
+        with tempfile.NamedTemporaryFile() as file:
+            return file.name
+
+
+    @contextlib.contextmanager
+    def unix_socket_path():
+        path = gen_unix_socket_path()
+        try:
+            yield path
+        finally:
+            try:
+                os.unlink(path)
+            except OSError:
+                pass
+
+
+    @contextlib.contextmanager
+    def run_test_unix_server(*, use_ssl=False):
+        with unix_socket_path() as path:
+            yield from _run_test_server(address=path, use_ssl=use_ssl,
+                                        server_cls=SilentUnixWSGIServer,
+                                        server_ssl_cls=UnixSSLWSGIServer)
+
+
+@contextlib.contextmanager
+def run_test_server(*, host='127.0.0.1', port=0, use_ssl=False):
+    yield from _run_test_server(address=(host, port), use_ssl=use_ssl,
+                                server_cls=SilentWSGIServer,
+                                server_ssl_cls=SSLWSGIServer)
+
+
 def make_test_protocol(base):
     dct = {}
     for name in dir(base):
@@ -275,5 +359,6 @@ class TestLoop(base_events.BaseEventLoop):
     def _write_to_self(self):
         pass
 
+
 def MockCallback(**kwargs):
     return unittest.mock.Mock(spec=['__call__'], **kwargs)

Lib/asyncio/unix_events.py

@@ -11,6 +11,7 @@ import sys
 import threading
 
 
+from . import base_events
 from . import base_subprocess
 from . import constants
 from . import events
@@ -31,9 +32,9 @@ if sys.platform == 'win32':  # pragma: no cover
 
 
 class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
-    """Unix event loop
+    """Unix event loop.
 
-    Adds signal handling to SelectorEventLoop
+    Adds signal handling and UNIX Domain Socket support to SelectorEventLoop.
     """
 
     def __init__(self, selector=None):
@@ -164,6 +165,76 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
     def _child_watcher_callback(self, pid, returncode, transp):
         self.call_soon_threadsafe(transp._process_exited, returncode)
 
+    @tasks.coroutine
+    def create_unix_connection(self, protocol_factory, path, *,
+                               ssl=None, sock=None,
+                               server_hostname=None):
+        assert server_hostname is None or isinstance(server_hostname, str)
+        if ssl:
+            if server_hostname is None:
+                raise ValueError(
+                    'you have to pass server_hostname when using ssl')
+        else:
+            if server_hostname is not None:
+                raise ValueError('server_hostname is only meaningful with ssl')
+
+        if path is not None:
+            if sock is not None:
+                raise ValueError(
+                    'path and sock can not be specified at the same time')
+
+            try:
+                sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM, 0)
+                sock.setblocking(False)
+                yield from self.sock_connect(sock, path)
+            except OSError:
+                if sock is not None:
+                    sock.close()
+                raise
+
+        else:
+            if sock is None:
+                raise ValueError('no path and sock were specified')
+            sock.setblocking(False)
+
+        transport, protocol = yield from self._create_connection_transport(
+            sock, protocol_factory, ssl, server_hostname)
+        return transport, protocol
+
+    @tasks.coroutine
+    def create_unix_server(self, protocol_factory, path=None, *,
+                           sock=None, backlog=100, ssl=None):
+        if isinstance(ssl, bool):
+            raise TypeError('ssl argument must be an SSLContext or None')
+
+        if path is not None:
+            sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+
+            try:
+                sock.bind(path)
+            except OSError as exc:
+                if exc.errno == errno.EADDRINUSE:
+                    # Let's improve the error message by adding
+                    # with what exact address it occurs.
+                    msg = 'Address {!r} is already in use'.format(path)
+                    raise OSError(errno.EADDRINUSE, msg) from None
+                else:
+                    raise
+        else:
+            if sock is None:
+                raise ValueError(
+                    'path was not specified, and no sock specified')
+
+            if sock.family != socket.AF_UNIX:
+                raise ValueError(
+                    'A UNIX Domain Socket was expected, got {!r}'.format(sock))
+
+        server = base_events.Server(self, [sock])
+        sock.listen(backlog)
+        sock.setblocking(False)
+        self._start_serving(protocol_factory, sock, ssl, server)
+        return server
+
 
 def _set_nonblocking(fd):
     flags = fcntl.fcntl(fd, fcntl.F_GETFL)

Lib/test/test_asyncio/test_base_events.py

@@ -212,7 +212,7 @@ class BaseEventLoopTests(unittest.TestCase):
 
         idx = -1
         data = [10.0, 10.0, 10.3, 13.0]
-        self.loop._scheduled = [asyncio.TimerHandle(11.0, lambda:True, ())]
+        self.loop._scheduled = [asyncio.TimerHandle(11.0, lambda: True, ())]
         self.loop._run_once()
         self.assertEqual(logging.DEBUG, m_logger.log.call_args[0][0])
 

Lib/test/test_asyncio/test_selector_events.py

@@ -55,7 +55,8 @@ class BaseSelectorEventLoopTests(unittest.TestCase):
         self.loop.remove_reader = unittest.mock.Mock()
         self.loop.remove_writer = unittest.mock.Mock()
         waiter = asyncio.Future(loop=self.loop)
-        transport = self.loop._make_ssl_transport(m, asyncio.Protocol(), m, waiter)
+        transport = self.loop._make_ssl_transport(
+            m, asyncio.Protocol(), m, waiter)
         self.assertIsInstance(transport, _SelectorSslTransport)
 
     @unittest.mock.patch('asyncio.selector_events.ssl', None)

Lib/test/test_asyncio/test_unix_events.py

@@ -7,8 +7,10 @@ import io
 import os
 import pprint
 import signal
+import socket
 import stat
 import sys
+import tempfile
 import threading
 import unittest
 import unittest.mock
@@ -24,7 +26,7 @@ from asyncio import unix_events
 
 
 @unittest.skipUnless(signal, 'Signals are not supported')
-class SelectorEventLoopTests(unittest.TestCase):
+class SelectorEventLoopSignalTests(unittest.TestCase):
 
     def setUp(self):
         self.loop = asyncio.SelectorEventLoop()
@@ -200,6 +202,84 @@ class SelectorEventLoopTests(unittest.TestCase):
         m_signal.set_wakeup_fd.assert_called_once_with(-1)
 
 
+@unittest.skipUnless(hasattr(socket, 'AF_UNIX'),
+                     'UNIX Sockets are not supported')
+class SelectorEventLoopUnixSocketTests(unittest.TestCase):
+
+    def setUp(self):
+        self.loop = asyncio.SelectorEventLoop()
+        asyncio.set_event_loop(None)
+
+    def tearDown(self):
+        self.loop.close()
+
+    def test_create_unix_server_existing_path_sock(self):
+        with test_utils.unix_socket_path() as path:
+            sock = socket.socket(socket.AF_UNIX)
+            sock.bind(path)
+
+            coro = self.loop.create_unix_server(lambda: None, path)
+            with self.assertRaisesRegexp(OSError,
+                                         'Address.*is already in use'):
+                self.loop.run_until_complete(coro)
+
+    def test_create_unix_server_existing_path_nonsock(self):
+        with tempfile.NamedTemporaryFile() as file:
+            coro = self.loop.create_unix_server(lambda: None, file.name)
+            with self.assertRaisesRegexp(OSError,
+                                         'Address.*is already in use'):
+                self.loop.run_until_complete(coro)
+
+    def test_create_unix_server_ssl_bool(self):
+        coro = self.loop.create_unix_server(lambda: None, path='spam',
+                                            ssl=True)
+        with self.assertRaisesRegex(TypeError,
+                                    'ssl argument must be an SSLContext'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_server_nopath_nosock(self):
+        coro = self.loop.create_unix_server(lambda: None, path=None)
+        with self.assertRaisesRegex(ValueError,
+                                    'path was not specified, and no sock'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_server_path_inetsock(self):
+        coro = self.loop.create_unix_server(lambda: None, path=None,
+                                            sock=socket.socket())
+        with self.assertRaisesRegex(ValueError,
+                                    'A UNIX Domain Socket was expected'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_connection_path_sock(self):
+        coro = self.loop.create_unix_connection(
+            lambda: None, '/dev/null', sock=object())
+        with self.assertRaisesRegex(ValueError, 'path and sock can not be'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_connection_nopath_nosock(self):
+        coro = self.loop.create_unix_connection(
+            lambda: None, None)
+        with self.assertRaisesRegex(ValueError,
+                                    'no path and sock were specified'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_connection_nossl_serverhost(self):
+        coro = self.loop.create_unix_connection(
+            lambda: None, '/dev/null', server_hostname='spam')
+        with self.assertRaisesRegex(ValueError,
+                                    'server_hostname is only meaningful'):
+            self.loop.run_until_complete(coro)
+
+    def test_create_unix_connection_ssl_noserverhost(self):
+        coro = self.loop.create_unix_connection(
+            lambda: None, '/dev/null', ssl=True)
+
+        with self.assertRaisesRegexp(
+            ValueError, 'you have to pass server_hostname when using ssl'):
+
+            self.loop.run_until_complete(coro)
+
+
 class UnixReadPipeTransportTests(unittest.TestCase):
 
     def setUp(self):