Support for Unix Domain Socket

AUTHORS

@@ -1,2 +1,3 @@
 Masahiro Nakagawa <repeatedly _at_ gmail.com>
 INADA Naoki <songofacandy _at_ gmail.com>
+Harish Vishwanath <harish dot shastry at gmail dot com>

README.md

@@ -1,6 +1,39 @@
 <!--
 [![Build Status](https://travis-ci.org/msgpack/msgpack-rpc-python.png)](https://travis-ci.org/msgpack/msgpack-rpc-python)
 -->
+# Unix Domain Socket support
+Unix domain socket support is now available for msgpack-rpc. Sample examples below.
+
+## UDS examples
+
+### Server
+
+```python
+import msgpackrpc.udsaddress
+from msgpackrpc.transport import uds
+class SumServer(object):
+    def sum(self, x, y):
+        return x + y
+
+# Use builder as uds. default builder is tcp which creates tcp sockets
+server = msgpackrpc.Server(SumServer(), builder=uds)
+# Use UDSAddress instead of msgpackrpc.Address
+server.listen(msgpackrpc.udsaddress.UDSAddress('/tmp/exrpc'))
+server.start()
+```
+
+### Client
+```python
+import msgpackrpc.udsaddress
+from msgpackrpc.transport import uds
+
+#Use UDSAddress instead of default Address object
+client = msgpackrpc.Client(msgpackrpc.udsaddress.UDSAddress("/tmp/exrpc"), builder=uds)
+result = client.call('sum', 1, 2)  # = > 
+print "Sum of 1 and 2 : %d" % result
+```
+
+Go through the below sections for general usage of Message Pack RPC Library
 
 # MessagePack RPC for Python
 

example/uds_simpleclient.py

@@ -0,0 +1,11 @@
+'''
+@author: hvishwanath | harish.shastry@gmail.com
+'''
+
+import msgpackrpc.udsaddress
+from msgpackrpc.transport import uds
+
+#Use UDSAddress instead of default Address object
+client = msgpackrpc.Client(msgpackrpc.udsaddress.UDSAddress("/tmp/exrpc"), builder=uds)
+result = client.call('sum', 1, 2)  # = > 
+print "Sum of 1 and 2 : %d" % result

example/uds_simpleserver.py

@@ -0,0 +1,15 @@
+'''
+@author: hvishwanath | harish.shastry@gmail.com
+'''
+
+import msgpackrpc.udsaddress
+from msgpackrpc.transport import uds
+class SumServer(object):
+    def sum(self, x, y):
+        return x + y
+
+# Use builder as uds. default builder is tcp which creates tcp sockets
+server = msgpackrpc.Server(SumServer(), builder=uds)
+# Use UDSAddress instead of msgpackrpc.Address
+server.listen(msgpackrpc.udsaddress.UDSAddress('/tmp/exrpc'))
+server.start()

msgpackrpc/__init__.py

@@ -5,3 +5,4 @@
 from msgpackrpc.client import Client
 from msgpackrpc.server import Server
 from msgpackrpc.address import Address
+from msgpackrpc.udsaddress import UDSAddress

msgpackrpc/transport/uds.py

@@ -0,0 +1,53 @@
+'''
+@author: hvishwanath | harish.shastry@gmail.com
+'''
+
+import msgpackrpc.transport
+from tornado.netutil import bind_unix_socket
+from tornado import tcpserver
+from tornado.iostream import IOStream
+
+# Much of the implementation will be same as that of tcp module
+# Changes required for unix domain socket support are done in this module
+# Rest will be automatically used from tcp
+
+# Create namespace equals
+BaseSocket = msgpackrpc.transport.tcp.BaseSocket
+ClientSocket = msgpackrpc.transport.tcp.ClientSocket
+ClientTransport = msgpackrpc.transport.tcp.ClientTransport
+
+ServerSocket = msgpackrpc.transport.tcp.ServerSocket
+ServerTransport = msgpackrpc.transport.tcp.ServerTransport
+
+
+class UDSServer(tcpserver.TCPServer):
+    """Define a Unix domain socket server.
+    Instead of binding to TCP/IP socket, bind to UDS socket and listen"""
+
+    def __init__(self, io_loop=None, ssl_options=None):
+        tcpserver.TCPServer.__init__(self, io_loop=io_loop, ssl_options=ssl_options)
+
+    def listen(self, port, address=""):
+        """Bind to a unix domain socket and add to self.
+        Note that port in our case actually contains the uds file name"""
+
+        # Create a Unix domain socket and bind
+        socket = bind_unix_socket(port)
+
+        # Add to self
+        self.add_socket(socket)
+
+class MessagePackServer(UDSServer):
+    """The MessagePackServer inherits from UDSServer
+    instead of tornado's TCP Server"""
+
+    def __init__(self, transport, io_loop=None, encodings=None):
+        self._transport = transport
+        self._encodings = encodings
+        UDSServer.__init__(self, io_loop=io_loop)
+
+    def handle_stream(self, stream, address):
+        ServerSocket(stream, self._transport, self._encodings)
+
+#Monkey patch the MessagePackServer
+msgpackrpc.transport.tcp.MessagePackServer = MessagePackServer

msgpackrpc/udsaddress.py

@@ -0,0 +1,40 @@
+'''
+@author: hvishwanath | harish.shastry@gmail.com
+'''
+
+import socket
+from tornado.platform.auto import set_close_exec
+
+class UDSAddress(object):
+    """This class abstracts Unix domain socket address.
+    For compatibility with other code in the library, port is always equal to host"""
+
+    def __init__(self, host, port=None):
+        self._host = host
+
+        # Passed value for port is ignored.
+        # Port is also made equal to host. 
+        # This is because some of the code in transport.tcp uses address._port to connect.
+        # For a unix socket, there is no port. Hence if port = host, that code should work.
+        self._port = host 
+
+    @property
+    def host(self):
+        return self._host
+
+    @property
+    def port(self):
+        return self._port
+
+    def unpack(self):
+        # Return only the host
+        return self._host
+
+    def socket(self, family=socket.AF_UNSPEC):
+        """Return a Unix domain socket instead of tcp socket"""
+
+        sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+        set_close_exec(sock.fileno())
+        sock.setblocking(0)
+
+        return sock

test/test_uds_msgpackrpc.py

@@ -0,0 +1,202 @@
+'''
+@author: hvishwanath | harish.shastry@gmail.com
+'''
+
+from msgpackrpc.transport import uds
+from time import sleep
+import threading
+try:
+    import unittest2 as unittest
+except ImportError:
+    import unittest
+
+import helper
+import msgpackrpc
+from msgpackrpc import error
+
+class TestMessagePackRPC(unittest.TestCase):
+    ENABLE_TIMEOUT_TEST = False
+
+    class TestArg:
+        ''' this class must know completely how to deserialize '''
+        def __init__(self, a, b, c):
+            self.a = a
+            self.b = b
+            self.c = c
+
+        def to_msgpack(self):
+            return (self.a, self.b, self.c)
+
+        def add(self, rhs):
+            self.a += rhs.a
+            self.b -= rhs.b
+            self.c *= rhs.c
+            return self
+
+        def __eq__(self, rhs):
+            return (self.a == rhs.a and self.b == rhs.b and self.c == rhs.c)
+
+        @staticmethod
+        def from_msgpack(arg):
+            return TestMessagePackRPC.TestArg(arg[0], arg[1], arg[2])
+
+    class TestServer(object):
+        def hello(self):
+            return "world"
+
+        def sum(self, x, y):
+            return x + y
+
+        def nil(self):
+            return None
+
+        def add_arg(self, arg0, arg1):
+            lhs = TestMessagePackRPC.TestArg.from_msgpack(arg0)
+            rhs = TestMessagePackRPC.TestArg.from_msgpack(arg1)
+            return lhs.add(rhs)
+
+        def raise_error(self):
+            raise Exception('error')
+
+        def long_exec(self):
+            sleep(3)
+            return 'finish!'
+
+        def async_result(self):
+            ar = msgpackrpc.server.AsyncResult()
+            def do_async():
+                sleep(2)
+                ar.set_result("You are async!")
+            threading.Thread(target=do_async).start()
+            return ar
+
+    def setUp(self):
+        # Create UDSAddress
+        self._address = msgpackrpc.UDSAddress('/tmp/unusedsocket')
+
+    def setup_env(self):
+        def _on_started():
+            self._server._loop.dettach_periodic_callback()
+            lock.release()
+        def _start_server(server):
+            server._loop.attach_periodic_callback(_on_started, 1)
+            server.start()
+            server.close()
+
+        # Use builder=uds
+        self._server = msgpackrpc.Server(TestMessagePackRPC.TestServer(), builder=uds)
+        self._server.listen(self._address)
+        self._thread = threading.Thread(target=_start_server, args=(self._server,))
+
+        lock = threading.Lock()
+        self._thread.start()
+        lock.acquire()
+        lock.acquire()   # wait for the server to start
+
+        self._client = msgpackrpc.Client(self._address, unpack_encoding='utf-8')
+        return self._client;
+
+    def tearDown(self):
+        self._client.close();
+        self._server.stop();
+        self._thread.join();
+
+    def test_call(self):
+        client = self.setup_env();
+
+        result1 = client.call('hello')
+        result2 = client.call('sum', 1, 2)
+        result3 = client.call('nil')
+
+        self.assertEqual(result1, "world", "'hello' result is incorrect")
+        self.assertEqual(result2, 3, "'sum' result is incorrect")
+        self.assertIsNone(result3, "'nil' result is incorrect")
+
+    def test_call_userdefined_arg(self):
+        client = self.setup_env();
+
+        arg = TestMessagePackRPC.TestArg(0, 1, 2)
+        arg2 = TestMessagePackRPC.TestArg(23, 3, -23)
+
+        result1 = TestMessagePackRPC.TestArg.from_msgpack(client.call('add_arg', arg, arg2))
+        self.assertEqual(result1, arg.add(arg2))
+
+        result2 = TestMessagePackRPC.TestArg.from_msgpack(client.call('add_arg', arg2, arg))
+        self.assertEqual(result2, arg2.add(arg))
+
+        result3 = TestMessagePackRPC.TestArg.from_msgpack(client.call('add_arg', result1, result2))
+        self.assertEqual(result3, result1.add(result2))
+
+    def test_call_async(self):
+        client = self.setup_env();
+
+        future1 = client.call_async('hello')
+        future2 = client.call_async('sum', 1, 2)
+        future3 = client.call_async('nil')
+        future1.join()
+        future2.join()
+        future3.join()
+
+        self.assertEqual(future1.result, "world", "'hello' result is incorrect in call_async")
+        self.assertEqual(future2.result, 3, "'sum' result is incorrect in call_async")
+        self.assertIsNone(future3.result, "'nil' result is incorrect in call_async")
+
+    def test_notify(self):
+        client = self.setup_env();
+
+        result = True
+        try:
+            client.notify('hello')
+            client.notify('sum', 1, 2)
+            client.notify('nil')
+        except:
+            result = False
+
+        self.assertTrue(result)
+
+    def test_raise_error(self):
+        client = self.setup_env();
+        self.assertRaises(error.RPCError, lambda: client.call('raise_error'))
+
+    def test_unknown_method(self):
+        client = self.setup_env();
+        self.assertRaises(error.RPCError, lambda: client.call('unknown', True))
+        try:
+            client.call('unknown', True)
+            self.assertTrue(False)
+        except error.RPCError as e:
+            message = e.args[0]
+            self.assertEqual(message, "'unknown' method not found", "Error message mismatched")
+
+    def test_async_result(self):
+        client = self.setup_env();
+        self.assertEqual(client.call('async_result'), "You are async!")
+
+    def test_connect_failed(self):
+        client = self.setup_env();
+        port = helper.unused_port()
+        client = msgpackrpc.Client(msgpackrpc.Address('localhost', port), unpack_encoding='utf-8')
+        self.assertRaises(error.TransportError, lambda: client.call('hello'))
+
+    def test_timeout(self):
+        client = self.setup_env();
+
+        if self.__class__.ENABLE_TIMEOUT_TEST:
+            self.assertEqual(client.call('long_exec'), 'finish!', "'long_exec' result is incorrect")
+
+            client = msgpackrpc.Client(self._address, timeout=1, unpack_encoding='utf-8')
+            self.assertRaises(error.TimeoutError, lambda: client.call('long_exec'))
+        else:
+            print("Skip test_timeout")
+
+
+if __name__ == '__main__':
+    import sys
+
+    try:
+        sys.argv.remove('--timeout-test')
+        TestMessagePackRPC.ENABLE_TIMEOUT_TEST = True
+    except:
+        pass
+
+    unittest.main()