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Diffstat (limited to 'testing/mochitest/pywebsocket/mod_pywebsocket/msgutil.py')
| -rw-r--r-- | testing/mochitest/pywebsocket/mod_pywebsocket/msgutil.py | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/testing/mochitest/pywebsocket/mod_pywebsocket/msgutil.py b/testing/mochitest/pywebsocket/mod_pywebsocket/msgutil.py new file mode 100644 index 000000000..4c1a0114b --- /dev/null +++ b/testing/mochitest/pywebsocket/mod_pywebsocket/msgutil.py @@ -0,0 +1,219 @@ +# Copyright 2011, Google Inc. +# All rights reserved. +# +# Redistribution and use in source and binary forms, with or without +# modification, are permitted provided that the following conditions are +# met: +# +# * Redistributions of source code must retain the above copyright +# notice, this list of conditions and the following disclaimer. +# * Redistributions in binary form must reproduce the above +# copyright notice, this list of conditions and the following disclaimer +# in the documentation and/or other materials provided with the +# distribution. +# * Neither the name of Google Inc. nor the names of its +# contributors may be used to endorse or promote products derived from +# this software without specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + + +"""Message related utilities. + +Note: request.connection.write/read are used in this module, even though +mod_python document says that they should be used only in connection +handlers. Unfortunately, we have no other options. For example, +request.write/read are not suitable because they don't allow direct raw +bytes writing/reading. +""" + + +import Queue +import threading + + +# Export Exception symbols from msgutil for backward compatibility +from mod_pywebsocket._stream_base import ConnectionTerminatedException +from mod_pywebsocket._stream_base import InvalidFrameException +from mod_pywebsocket._stream_base import BadOperationException +from mod_pywebsocket._stream_base import UnsupportedFrameException + + +# An API for handler to send/receive WebSocket messages. +def close_connection(request): + """Close connection. + + Args: + request: mod_python request. + """ + request.ws_stream.close_connection() + + +def send_message(request, payload_data, end=True, binary=False): + """Send a message (or part of a message). + + Args: + request: mod_python request. + payload_data: unicode text or str binary to send. + end: True to terminate a message. + False to send payload_data as part of a message that is to be + terminated by next or later send_message call with end=True. + binary: send payload_data as binary frame(s). + Raises: + BadOperationException: when server already terminated. + """ + request.ws_stream.send_message(payload_data, end, binary) + + +def receive_message(request): + """Receive a WebSocket frame and return its payload as a text in + unicode or a binary in str. + + Args: + request: mod_python request. + Raises: + InvalidFrameException: when client send invalid frame. + UnsupportedFrameException: when client send unsupported frame e.g. some + of reserved bit is set but no extension can + recognize it. + InvalidUTF8Exception: when client send a text frame containing any + invalid UTF-8 string. + ConnectionTerminatedException: when the connection is closed + unexpectedly. + BadOperationException: when client already terminated. + """ + return request.ws_stream.receive_message() + + +def send_ping(request, body=''): + request.ws_stream.send_ping(body) + + +class MessageReceiver(threading.Thread): + """This class receives messages from the client. + + This class provides three ways to receive messages: blocking, + non-blocking, and via callback. Callback has the highest precedence. + + Note: This class should not be used with the standalone server for wss + because pyOpenSSL used by the server raises a fatal error if the socket + is accessed from multiple threads. + """ + + def __init__(self, request, onmessage=None): + """Construct an instance. + + Args: + request: mod_python request. + onmessage: a function to be called when a message is received. + May be None. If not None, the function is called on + another thread. In that case, MessageReceiver.receive + and MessageReceiver.receive_nowait are useless + because they will never return any messages. + """ + + threading.Thread.__init__(self) + self._request = request + self._queue = Queue.Queue() + self._onmessage = onmessage + self._stop_requested = False + self.setDaemon(True) + self.start() + + def run(self): + try: + while not self._stop_requested: + message = receive_message(self._request) + if self._onmessage: + self._onmessage(message) + else: + self._queue.put(message) + finally: + close_connection(self._request) + + def receive(self): + """ Receive a message from the channel, blocking. + + Returns: + message as a unicode string. + """ + return self._queue.get() + + def receive_nowait(self): + """ Receive a message from the channel, non-blocking. + + Returns: + message as a unicode string if available. None otherwise. + """ + try: + message = self._queue.get_nowait() + except Queue.Empty: + message = None + return message + + def stop(self): + """Request to stop this instance. + + The instance will be stopped after receiving the next message. + This method may not be very useful, but there is no clean way + in Python to forcefully stop a running thread. + """ + self._stop_requested = True + + +class MessageSender(threading.Thread): + """This class sends messages to the client. + + This class provides both synchronous and asynchronous ways to send + messages. + + Note: This class should not be used with the standalone server for wss + because pyOpenSSL used by the server raises a fatal error if the socket + is accessed from multiple threads. + """ + + def __init__(self, request): + """Construct an instance. + + Args: + request: mod_python request. + """ + threading.Thread.__init__(self) + self._request = request + self._queue = Queue.Queue() + self.setDaemon(True) + self.start() + + def run(self): + while True: + message, condition = self._queue.get() + condition.acquire() + send_message(self._request, message) + condition.notify() + condition.release() + + def send(self, message): + """Send a message, blocking.""" + + condition = threading.Condition() + condition.acquire() + self._queue.put((message, condition)) + condition.wait() + + def send_nowait(self, message): + """Send a message, non-blocking.""" + + self._queue.put((message, threading.Condition())) + + +# vi:sts=4 sw=4 et |