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"""
websocket - WebSocket client library for Python
Copyright (C) 2010 Hiroki Ohtani(liris)
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""
"""
This code adopted from:
http://pypi.python.org/pypi/websocket-client/0.4
Minor modifications made by Sam Birch:
- Updated to use hashlib from md5, which is deprecated since 2.5
- Assorted code clean-up
"""
import socket
from urlparse import urlparse
import random
import struct
import hashlib
import logging
logger = logging.getLogger()
class WebSocketException(Exception):
pass
class ConnectionClosedException(WebSocketException):
pass
default_timeout = None
traceEnabled = False
def enableTrace(tracable):
"""
turn on/off the tracability.
"""
global traceEnabled
traceEnabled = tracable
if tracable:
if not logger.handlers:
logger.addHandler(logging.StreamHandler())
logger.setLevel(logging.DEBUG)
def setdefaulttimeout(timeout):
"""
Set the global timeout setting to connect.
"""
global default_timeout
default_timeout = timeout
def getdefaulttimeout():
"""
Return the global timeout setting to connect.
"""
return default_timeout
def _parse_url(url):
"""
parse url and the result is tuple of
(hostname, port, resource path and the flag of secure mode)
"""
parsed = urlparse(url)
if parsed.hostname:
hostname = parsed.hostname
else:
raise ValueError("hostname is invalid")
port = 0
if parsed.port:
port = parsed.port
is_secure = False
if parsed.scheme == "ws":
if not port:
port = 80
elif parsed.scheme == "wss":
is_secure = True
if not port:
port = 443
else:
raise ValueError("scheme %s is invalid" % parsed.scheme)
if parsed.path:
resource = parsed.path
else:
resource = "/"
return (hostname, port, resource, is_secure)
def create_connection(url, timeout=None, **options):
"""
connect to url and return websocket object.
Connect to url and return the WebSocket object.
Passing optional timeout parameter will set the timeout on the socket.
If no timeout is supplied, the global default timeout setting returned by getdefauttimeout() is used.
"""
websock = WebSocket()
websock.settimeout(timeout != None and timeout or default_timeout)
websock.connect(url, **options)
return websock
_MAX_INTEGER = (1 << 32) -1
_AVAILABLE_KEY_CHARS = range(0x21, 0x2f + 1) + range(0x3a, 0x7e + 1)
_MAX_CHAR_BYTE = (1<<8) -1
# ref. Websocket gets an update, and it breaks stuff.
# http://axod.blogspot.com/2010/06/websocket-gets-update-and-it-breaks.html
def _create_sec_websocket_key():
spaces_n = random.randint(1, 12)
max_n = _MAX_INTEGER / spaces_n
number_n = random.randint(0, max_n)
product_n = number_n * spaces_n
key_n = str(product_n)
for i in range(random.randint(1, 12)):
c = random.choice(_AVAILABLE_KEY_CHARS)
pos = random.randint(0, len(key_n))
key_n = key_n[0:pos] + chr(c) + key_n[pos:]
for i in range(spaces_n):
pos = random.randint(1, len(key_n)-1)
key_n = key_n[0:pos] + " " + key_n[pos:]
return number_n, key_n
def _create_key3():
return "".join([chr(random.randint(0, _MAX_CHAR_BYTE)) for i in range(8)])
HEADERS_TO_CHECK = {
"upgrade": "websocket",
"connection": "upgrade",
}
HEADERS_TO_EXIST_FOR_HYBI00 = [
"sec-websocket-origin",
"sec-websocket-location",
]
HEADERS_TO_EXIST_FOR_HIXIE75 = [
"websocket-origin",
"websocket-location",
]
class _SSLSocketWrapper(object):
def __init__(self, sock):
self.ssl = socket.ssl(sock)
def recv(self, bufsize):
return self.ssl.read(bufsize)
def send(self, payload):
return self.ssl.write(payload)
class WebSocket(object):
"""
Low level WebSocket interface.
This class is based on
The WebSocket protocol draft-hixie-thewebsocketprotocol-76
http://tools.ietf.org/html/draft-hixie-thewebsocketprotocol-76
We can connect to the websocket server and send/recieve data.
The following example is a echo client.
>>> import websocket
>>> ws = websocket.WebSocket()
>>> ws.Connect("ws://localhost:8080/echo")
>>> ws.send("Hello, Server")
>>> ws.recv()
'Hello, Server'
>>> ws.close()
"""
def __init__(self):
"""
Initalize WebSocket object.
"""
self.connected = False
self.io_sock = self.sock = socket.socket()
def settimeout(self, timeout):
"""
Set the timeout to the websocket.
"""
self.sock.settimeout(timeout)
def gettimeout(self):
"""
Get the websocket timeout.
"""
return self.sock.gettimeout()
def connect(self, url, **options):
"""
Connect to url. url is websocket url scheme. ie. ws://host:port/resource
"""
hostname, port, resource, is_secure = _parse_url(url)
# TODO: we need to support proxy
self.sock.connect((hostname, port))
if is_secure:
self.io_sock = _SSLSocketWrapper(self.sock)
self._handshake(hostname, port, resource, **options)
def _handshake(self, host, port, resource, **options):
sock = self.io_sock
headers = []
if "header" in options:
headers.extend(options["header"])
headers.append("GET %s HTTP/1.1" % resource)
headers.append("Upgrade: WebSocket")
headers.append("Connection: Upgrade")
if port == 80:
hostport = host
else:
hostport = "%s:%d" % (host, port)
headers.append("Host: %s" % hostport)
headers.append("Origin: %s" % hostport)
number_1, key_1 = _create_sec_websocket_key()
headers.append("Sec-WebSocket-Key1: %s" % key_1)
number_2, key_2 = _create_sec_websocket_key()
headers.append("Sec-WebSocket-Key2: %s" % key_2)
headers.append("")
key3 = _create_key3()
headers.append(key3)
header_str = "\r\n".join(headers)
sock.send(header_str)
if traceEnabled:
logger.debug( "--- request header ---")
logger.debug( header_str)
logger.debug("-----------------------")
status, resp_headers = self._read_headers()
if status != 101:
self.close()
raise WebSocketException("Handshake Status %d" % status)
success, secure = self._validate_header(resp_headers)
if not success:
self.close()
raise WebSocketException("Invalid WebSocket Header")
if secure:
resp = self._get_resp()
if not self._validate_resp(number_1, number_2, key3, resp):
self.close()
raise WebSocketException("challenge-response error")
self.connected = True
def _validate_resp(self, number_1, number_2, key3, resp):
challenge = struct.pack("!I", number_1)
challenge += struct.pack("!I", number_2)
challenge += key3
digest = hashlib.md5(challenge).digest()
return resp == digest
def _get_resp(self):
result = self._recv(16)
if traceEnabled:
logger.debug("--- challenge response result ---")
logger.debug(repr(result))
logger.debug("---------------------------------")
return result
def _validate_header(self, headers):
#TODO: check other headers
for key, value in HEADERS_TO_CHECK.iteritems():
v = headers.get(key, None)
if value != v:
return False, False
success = 0
for key in HEADERS_TO_EXIST_FOR_HYBI00:
if key in headers:
success += 1
if success == len(HEADERS_TO_EXIST_FOR_HYBI00):
return True, True
elif success != 0:
return False, True
success = 0
for key in HEADERS_TO_EXIST_FOR_HIXIE75:
if key in headers:
success += 1
if success == len(HEADERS_TO_EXIST_FOR_HIXIE75):
return True, False
return False, False
def _read_headers(self):
status = None
headers = {}
if traceEnabled:
logger.debug("--- response header ---")
while True:
line = self._recv_line()
if line == "\r\n":
break
line = line.strip()
if traceEnabled:
logger.debug(line)
if not status:
status_info = line.split(" ", 2)
status = int(status_info[1])
else:
kv = line.split(":", 1)
if len(kv) == 2:
key, value = kv
headers[key.lower()] = value.strip().lower()
else:
raise WebSocketException("Invalid header")
if traceEnabled:
logger.debug("-----------------------")
return status, headers
def send(self, payload):
"""
Send the data as string. payload must be utf-8 string or unicode.
"""
if isinstance(payload, unicode):
payload = payload.encode("utf-8")
data = "".join(["\x00", payload, "\xff"])
self.io_sock.send(data)
if traceEnabled:
logger.debug("send: " + repr(data))
def recv(self):
"""
Reeive utf-8 string data from the server.
"""
b = self._recv(1)
if enableTrace:
logger.debug("recv frame: " + repr(b))
frame_type = ord(b)
if frame_type == 0x00:
bytes = []
while True:
b = self._recv(1)
if b == "\xff":
break
else:
bytes.append(b)
return "".join(bytes)
elif 0x80 < frame_type < 0xff:
# which frame type is valid?
length = self._read_length()
bytes = self._recv_strict(length)
return bytes
elif frame_type == 0xff:
n = self._recv(1)
self._closeInternal()
return None
else:
raise WebSocketException("Invalid frame type")
def _read_length(self):
length = 0
while True:
b = ord(self._recv(1))
length = length * (1 << 7) + (b & 0x7f)
if b < 0x80:
break
return length
def close(self):
"""
Close Websocket object
"""
if self.connected:
try:
self.io_sock.send("\xff\x00")
timeout = self.sock.gettimeout()
self.sock.settimeout(1)
try:
result = self._recv(2)
if result != "\xff\x00":
logger.error("bad closing Handshake")
except:
pass
self.sock.settimeout(timeout)
self.sock.shutdown(socket.SHUT_RDWR)
except:
pass
self._closeInternal()
def _closeInternal(self):
self.connected = False
self.sock.close()
self.io_sock = self.sock
def _recv(self, bufsize):
bytes = self.io_sock.recv(bufsize)
if not bytes:
raise ConnectionClosedException()
return bytes
def _recv_strict(self, bufsize):
remaining = bufsize
bytes = ""
while remaining:
bytes += self._recv(remaining)
remaining = bufsize - len(bytes)
return bytes
def _recv_line(self):
line = []
while True:
c = self._recv(1)
line.append(c)
if c == "\n":
break
return "".join(line)
class WebSocketApp(object):
"""
Higher level of APIs are provided.
The interface is like JavaScript WebSocket object.
"""
def __init__(self, url,
on_open = None, on_message = None, on_error = None,
on_close = None):
"""
url: websocket url.
on_open: callable object which is called at opening websocket.
this function has one argument. The arugment is this class object.
on_message: callbale object which is called when recieved data.
on_message has 2 arguments.
The 1st arugment is this class object.
The passing 2nd arugment is utf-8 string which we get from the server.
on_error: callable object which is called when we get error.
on_error has 2 arguments.
The 1st arugment is this class object.
The passing 2nd arugment is exception object.
on_close: callable object which is called when closed the connection.
this function has one argument. The arugment is this class object.
"""
self.url = url
self.on_open = on_open
self.on_message = on_message
self.on_error = on_error
self.on_close = on_close
self.sock = None
def send(self, data):
"""
send message. data must be utf-8 string or unicode.
"""
self.sock.send(data)
def close(self):
"""
close websocket connection.
"""
self.sock.close()
def run_forever(self):
"""
run event loop for WebSocket framework.
This loop is infinite loop and is alive during websocket is available.
"""
if self.sock:
raise WebSocketException("socket is already opened")
try:
self.sock = WebSocket()
self.sock.connect(self.url)
self._run_with_no_err(self.on_open)
while True:
data = self.sock.recv()
if data is None:
break
self._run_with_no_err(self.on_message, data)
except Exception, e:
self._run_with_no_err(self.on_error, e)
finally:
self.sock.close()
self._run_with_no_err(self.on_close)
self.sock = None
def _run_with_no_err(self, callback, *args):
if callback:
try:
callback(self, *args)
except Exception, e:
if logger.isEnabledFor(logging.DEBUG):
logger.error(e)
if __name__ == "__main__":
enableTrace(True)
ws = create_connection("ws://localhost:5000/chat")
print "Sending 'Hello, World'..."
ws.send("Hello, World")
print "Sent"
print "Receiving..."
result = ws.recv()
print "Received '%s'" % result
ws.close()