15c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# Copyright 2011, Google Inc. 25c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# All rights reserved. 35c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# 45c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# Redistribution and use in source and binary forms, with or without 55c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# modification, are permitted provided that the following conditions are 65c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# met: 75c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# 85c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# * Redistributions of source code must retain the above copyright 95c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# notice, this list of conditions and the following disclaimer. 105c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# * Redistributions in binary form must reproduce the above 115c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# copyright notice, this list of conditions and the following disclaimer 125c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# in the documentation and/or other materials provided with the 135c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# distribution. 145c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# * Neither the name of Google Inc. nor the names of its 155c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# contributors may be used to endorse or promote products derived from 165c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# this software without specific prior written permission. 175c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# 185c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 195c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 205c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 215c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 225c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 235c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 245c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 255c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 265c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 275c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 285c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 295c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 305c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 315c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)"""Base stream class. 325c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)""" 335c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 345c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 355c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# Note: request.connection.write/read are used in this module, even though 365c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# mod_python document says that they should be used only in connection 375c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# handlers. Unfortunately, we have no other options. For example, 385c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# request.write/read are not suitable because they don't allow direct raw bytes 395c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# writing/reading. 405c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 415c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 4253e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles)import socket 4353e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) 445c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)from mod_pywebsocket import util 455c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 465c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 475c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# Exceptions 485c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 495c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 505c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class ConnectionTerminatedException(Exception): 515c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """This exception will be raised when a connection is terminated 525c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) unexpectedly. 535c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 545c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 555c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) pass 565c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 575c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 585c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class InvalidFrameException(ConnectionTerminatedException): 595c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """This exception will be raised when we received an invalid frame we 605c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) cannot parse. 615c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 625c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 635c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) pass 645c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 655c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 665c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class BadOperationException(Exception): 675c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """This exception will be raised when send_message() is called on 685c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) server-terminated connection or receive_message() is called on 695c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) client-terminated connection. 705c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 715c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 725c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) pass 735c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 745c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 755c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class UnsupportedFrameException(Exception): 765c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """This exception will be raised when we receive a frame with flag, opcode 775c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) we cannot handle. Handlers can just catch and ignore this exception and 785c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) call receive_message() again to continue processing the next frame. 795c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 805c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 815c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) pass 825c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 835c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 845c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class InvalidUTF8Exception(Exception): 855c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """This exception will be raised when we receive a text frame which 865c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) contains invalid UTF-8 strings. 875c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 885c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 895c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) pass 905c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 915c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 925c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)class StreamBase(object): 935c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Base stream class.""" 945c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 955c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) def __init__(self, request): 965c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Construct an instance. 975c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 985c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) Args: 995c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) request: mod_python request. 1005c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 1015c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1025c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) self._logger = util.get_class_logger(self) 1035c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1045c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) self._request = request 1055c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1065c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) def _read(self, length): 1075c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Reads length bytes from connection. In case we catch any exception, 1085c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) prepends remote address to the exception message and raise again. 1095c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1105c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) Raises: 1115c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) ConnectionTerminatedException: when read returns empty string. 1125c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 1135c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 11453e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) try: 11553e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) read_bytes = self._request.connection.read(length) 11653e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) if not read_bytes: 11753e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) raise ConnectionTerminatedException( 11853e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) 'Receiving %d byte failed. Peer (%r) closed connection' % 11953e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) (length, (self._request.connection.remote_addr,))) 12053e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) return read_bytes 12153e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) except socket.error, e: 12253e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) # Catch a socket.error. Because it's not a child class of the 12353e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) # IOError prior to Python 2.6, we cannot omit this except clause. 12453e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) # Use %s rather than %r for the exception to use human friendly 12553e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) # format. 12653e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) raise ConnectionTerminatedException( 12753e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) 'Receiving %d byte failed. socket.error (%s) occurred' % 12853e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) (length, e)) 12953e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) except IOError, e: 13053e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) # Also catch an IOError because mod_python throws it. 1315c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) raise ConnectionTerminatedException( 13253e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) 'Receiving %d byte failed. IOError (%s) occurred' % 13353e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) (length, e)) 1345c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 13553e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) def _write(self, bytes_to_write): 1365c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Writes given bytes to connection. In case we catch any exception, 1375c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) prepends remote address to the exception message and raise again. 1385c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 1395c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1405c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) try: 14153e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) self._request.connection.write(bytes_to_write) 1425c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) except Exception, e: 1435c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) util.prepend_message_to_exception( 1445c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 'Failed to send message to %r: ' % 1455c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) (self._request.connection.remote_addr,), 1465c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) e) 1475c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) raise 1485c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1495c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) def receive_bytes(self, length): 1505c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Receives multiple bytes. Retries read when we couldn't receive the 1515c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) specified amount. 1525c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1535c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) Raises: 1545c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) ConnectionTerminatedException: when read returns empty string. 1555c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 1565c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 15753e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) read_bytes = [] 1585c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) while length > 0: 15953e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) new_read_bytes = self._read(length) 16053e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) read_bytes.append(new_read_bytes) 16153e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) length -= len(new_read_bytes) 16253e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) return ''.join(read_bytes) 1635c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1645c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) def _read_until(self, delim_char): 1655c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """Reads bytes until we encounter delim_char. The result will not 1665c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) contain delim_char. 1675c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1685c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) Raises: 1695c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) ConnectionTerminatedException: when read returns empty string. 1705c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) """ 1715c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 17253e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) read_bytes = [] 1735c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) while True: 1745c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) ch = self._read(1) 1755c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) if ch == delim_char: 1765c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) break 17753e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) read_bytes.append(ch) 17853e740f4a82e17f3ae59772501622dc354e42336Torne (Richard Coles) return ''.join(read_bytes) 1795c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1805c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles) 1815c87bf8b86a7c82ef50fb7a89697d8e02e2553beTorne (Richard Coles)# vi:sts=4 sw=4 et 182