python-websockets: backport fix for upstream issue #350

Signed-off-by: Joseph Kogut <joseph.kogut@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 439e2add6c39bb128e1a5f1fb624ecfb99948d5e)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python-websockets/0001-Fix-behavior-of-recv-in-the-CLOSING-state.patch

@@ -0,0 +1,261 @@
+From 402059e4a46a764632eba8a669f5b012f173ee7b Mon Sep 17 00:00:00 2001
+From: Aymeric Augustin <aymeric.augustin@m4x.org>
+Date: Tue, 1 May 2018 17:05:05 +0200
+Subject: [PATCH] Fix behavior of recv() in the CLOSING state.
+
+The behavior wasn't tested correctly: in some test cases, the connection
+had already moved to the CLOSED state, where the close code and reason
+are already known.
+
+Refactor half_close_connection_{local,remote} to allow multiple runs of
+the event loop while remaining in the CLOSING state. Refactor affected
+tests accordingly.
+
+I verified that all tests in the CLOSING state were behaving is intended
+by inserting debug statements in recv/send/ping/pong and running:
+
+$ PYTHONASYNCIODEBUG=1 python -m unittest -v websockets.test_protocol.{Client,Server}Tests.test_{recv,send,ping,pong}_on_closing_connection_{local,remote}
+
+Fix #317, #327, #350, #357.
+
+Signed-off-by: Joseph Kogut <joseph.kogut@gmail.com>
+---
+ websockets/protocol.py      | 10 ++---
+ websockets/test_protocol.py | 78 +++++++++++++++++++++++++++++--------
+ 2 files changed, 66 insertions(+), 22 deletions(-)
+
+diff --git a/websockets/protocol.py b/websockets/protocol.py
+index f8121a1..7583fe9 100644
+--- a/websockets/protocol.py
++++ b/websockets/protocol.py
+@@ -303,7 +303,7 @@ class WebSocketCommonProtocol(asyncio.StreamReaderProtocol):
+         # Don't yield from self.ensure_open() here because messages could be
+         # received before the closing frame even if the connection is closing.
+ 
+-        # Wait for a message until the connection is closed
++        # Wait for a message until the connection is closed.
+         next_message = asyncio_ensure_future(
+             self.messages.get(), loop=self.loop)
+         try:
+@@ -315,15 +315,15 @@ class WebSocketCommonProtocol(asyncio.StreamReaderProtocol):
+             next_message.cancel()
+             raise
+ 
+-        # Now there's no need to yield from self.ensure_open(). Either a
+-        # message was received or the connection was closed.
+-
+         if next_message in done:
+             return next_message.result()
+         else:
+             next_message.cancel()
+             if not self.legacy_recv:
+-                raise ConnectionClosed(self.close_code, self.close_reason)
++                assert self.state in [State.CLOSING, State.CLOSED]
++                # Wait until the connection is closed to raise
++                # ConnectionClosed with the correct code and reason.
++                yield from self.ensure_open()
+ 
+     @asyncio.coroutine
+     def send(self, data):
+diff --git a/websockets/test_protocol.py b/websockets/test_protocol.py
+index 70348fb..bfd4e3b 100644
+--- a/websockets/test_protocol.py
++++ b/websockets/test_protocol.py
+@@ -105,7 +105,7 @@ class CommonTests:
+         self.loop.call_soon(self.loop.stop)
+         self.loop.run_forever()
+ 
+-    def make_drain_slow(self, delay=3 * MS):
++    def make_drain_slow(self, delay=MS):
+         # Process connection_made in order to initialize self.protocol.writer.
+         self.run_loop_once()
+ 
+@@ -174,6 +174,8 @@ class CommonTests:
+         # Empty the outgoing data stream so we can make assertions later on.
+         self.assertOneFrameSent(True, OP_CLOSE, close_frame_data)
+ 
++        assert self.protocol.state is State.CLOSED
++
+     def half_close_connection_local(self, code=1000, reason='close'):
+         """
+         Start a closing handshake but do not complete it.
+@@ -181,31 +183,56 @@ class CommonTests:
+         The main difference with `close_connection` is that the connection is
+         left in the CLOSING state until the event loop runs again.
+ 
++        The current implementation returns a task that must be awaited or
++        cancelled, else asyncio complains about destroying a pending task.
++
+         """
+         close_frame_data = serialize_close(code, reason)
+-        # Trigger the closing handshake from the local side.
+-        self.ensure_future(self.protocol.close(code, reason))
++        # Trigger the closing handshake from the local endpoint.
++        close_task = self.ensure_future(self.protocol.close(code, reason))
+         self.run_loop_once()    # wait_for executes
+         self.run_loop_once()    # write_frame executes
+         # Empty the outgoing data stream so we can make assertions later on.
+         self.assertOneFrameSent(True, OP_CLOSE, close_frame_data)
+-        # Prepare the response to the closing handshake from the remote side.
+-        self.loop.call_soon(
+-            self.receive_frame, Frame(True, OP_CLOSE, close_frame_data))
+-        self.loop.call_soon(self.receive_eof_if_client)
++
++        assert self.protocol.state is State.CLOSING
++
++        # Complete the closing sequence at 1ms intervals so the test can run
++        # at each point even it goes back to the event loop several times.
++        self.loop.call_later(
++            MS, self.receive_frame, Frame(True, OP_CLOSE, close_frame_data))
++        self.loop.call_later(2 * MS, self.receive_eof_if_client)
++
++        # This task must be awaited or cancelled by the caller.
++        return close_task
+ 
+     def half_close_connection_remote(self, code=1000, reason='close'):
+         """
+-        Receive a closing handshake.
++        Receive a closing handshake but do not complete it.
+ 
+         The main difference with `close_connection` is that the connection is
+         left in the CLOSING state until the event loop runs again.
+ 
+         """
++        # On the server side, websockets completes the closing handshake and
++        # closes the TCP connection immediately. Yield to the event loop after
++        # sending the close frame to run the test while the connection is in
++        # the CLOSING state.
++        if not self.protocol.is_client:
++            self.make_drain_slow()
++
+         close_frame_data = serialize_close(code, reason)
+-        # Trigger the closing handshake from the remote side.
++        # Trigger the closing handshake from the remote endpoint.
+         self.receive_frame(Frame(True, OP_CLOSE, close_frame_data))
+-        self.receive_eof_if_client()
++        self.run_loop_once()    # read_frame executes
++        # Empty the outgoing data stream so we can make assertions later on.
++        self.assertOneFrameSent(True, OP_CLOSE, close_frame_data)
++
++        assert self.protocol.state is State.CLOSING
++
++        # Complete the closing sequence at 1ms intervals so the test can run
++        # at each point even it goes back to the event loop several times.
++        self.loop.call_later(2 * MS, self.receive_eof_if_client)
+ 
+     def process_invalid_frames(self):
+         """
+@@ -335,11 +362,13 @@ class CommonTests:
+         self.assertEqual(data, b'tea')
+ 
+     def test_recv_on_closing_connection_local(self):
+-        self.half_close_connection_local()
++        close_task = self.half_close_connection_local()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.recv())
+ 
++        self.loop.run_until_complete(close_task)    # cleanup
++
+     def test_recv_on_closing_connection_remote(self):
+         self.half_close_connection_remote()
+ 
+@@ -421,24 +450,29 @@ class CommonTests:
+         self.assertNoFrameSent()
+ 
+     def test_send_on_closing_connection_local(self):
+-        self.half_close_connection_local()
++        close_task = self.half_close_connection_local()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.send('foobar'))
++
+         self.assertNoFrameSent()
+ 
++        self.loop.run_until_complete(close_task)    # cleanup
++
+     def test_send_on_closing_connection_remote(self):
+         self.half_close_connection_remote()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.send('foobar'))
+-        self.assertOneFrameSent(True, OP_CLOSE, serialize_close(1000, 'close'))
++
++        self.assertNoFrameSent()
+ 
+     def test_send_on_closed_connection(self):
+         self.close_connection()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.send('foobar'))
++
+         self.assertNoFrameSent()
+ 
+     # Test the ping coroutine.
+@@ -466,24 +500,29 @@ class CommonTests:
+         self.assertNoFrameSent()
+ 
+     def test_ping_on_closing_connection_local(self):
+-        self.half_close_connection_local()
++        close_task = self.half_close_connection_local()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.ping())
++
+         self.assertNoFrameSent()
+ 
++        self.loop.run_until_complete(close_task)    # cleanup
++
+     def test_ping_on_closing_connection_remote(self):
+         self.half_close_connection_remote()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.ping())
+-        self.assertOneFrameSent(True, OP_CLOSE, serialize_close(1000, 'close'))
++
++        self.assertNoFrameSent()
+ 
+     def test_ping_on_closed_connection(self):
+         self.close_connection()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.ping())
++
+         self.assertNoFrameSent()
+ 
+     # Test the pong coroutine.
+@@ -506,24 +545,29 @@ class CommonTests:
+         self.assertNoFrameSent()
+ 
+     def test_pong_on_closing_connection_local(self):
+-        self.half_close_connection_local()
++        close_task = self.half_close_connection_local()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.pong())
++
+         self.assertNoFrameSent()
+ 
++        self.loop.run_until_complete(close_task)    # cleanup
++
+     def test_pong_on_closing_connection_remote(self):
+         self.half_close_connection_remote()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.pong())
+-        self.assertOneFrameSent(True, OP_CLOSE, serialize_close(1000, 'close'))
++
++        self.assertNoFrameSent()
+ 
+     def test_pong_on_closed_connection(self):
+         self.close_connection()
+ 
+         with self.assertRaises(ConnectionClosed):
+             self.loop.run_until_complete(self.protocol.pong())
++
+         self.assertNoFrameSent()
+ 
+     # Test the protocol's logic for acknowledging pings with pongs.
+-- 
+2.17.0
+