""" 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 """ import socket from urlparse import urlparse import os import struct import uuid import hashlib import base64 import logging """ websocket python client. ========================= This version support only hybi-13. Please see http://tools.ietf.org/html/rfc6455 for protocol. """ # websocket supported version. VERSION = 13 # closing frame status codes. STATUS_NORMAL = 1000 STATUS_GOING_AWAY = 1001 STATUS_PROTOCOL_ERROR = 1002 STATUS_UNSUPPORTED_DATA_TYPE = 1003 STATUS_STATUS_NOT_AVAILABLE = 1005 STATUS_ABNORMAL_CLOSED = 1006 STATUS_INVALID_PAYLOAD = 1007 STATUS_POLICY_VIOLATION = 1008 STATUS_MESSAGE_TOO_BIG = 1009 STATUS_INVALID_EXTENSION = 1010 STATUS_UNEXPECTED_CONDITION = 1011 STATUS_TLS_HANDSHAKE_ERROR = 1015 logger = logging.getLogger() class WebSocketException(Exception): """ websocket exeception class. """ pass class WebSocketConnectionClosedException(WebSocketException): """ If remote host closed the connection or some network error happened, this exception will be raised. """ pass default_timeout = None traceEnabled = False def enableTrace(tracable): """ turn on/off the tracability. tracable: boolean value. if set True, tracability is enabled. """ 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. timeout: default socket timeout time. This value is second. """ global default_timeout default_timeout = timeout def getdefaulttimeout(): """ Return the global timeout setting(second) 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) url: url string. """ if ":" not in url: raise ValueError("url is invalid") scheme, url = url.split(":", 1) parsed = urlparse(url, scheme="http") if parsed.hostname: hostname = parsed.hostname else: raise ValueError("hostname is invalid") port = 0 if parsed.port: port = parsed.port is_secure = False if scheme == "ws": if not port: port = 80 elif scheme == "wss": is_secure = True if not port: port = 443 else: raise ValueError("scheme %s is invalid" % scheme) if parsed.path: resource = parsed.path else: resource = "/" if parsed.query: resource += "?" + parsed.query 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. You can customize using 'options'. If you set "header" dict object, you can set your own custom header. >>> conn = create_connection("ws://echo.websocket.org/", ... header={"User-Agent: MyProgram", ... "x-custom: header"}) timeout: socket timeout time. This value is integer. if you set None for this value, it means "use default_timeout value" options: current support option is only "header". if you set header as dict value, the custom HTTP headers are added. """ 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(): uid = uuid.uuid4() return base64.encodestring(uid.bytes).strip() _HEADERS_TO_CHECK = { "upgrade": "websocket", "connection": "upgrade", } 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) _BOOL_VALUES = (0, 1) def _is_bool(*values): for v in values: if v not in _BOOL_VALUES: return False return True class ABNF(object): """ ABNF frame class. see http://tools.ietf.org/html/rfc5234 and http://tools.ietf.org/html/rfc6455#section-5.2 """ # operation code values. OPCODE_TEXT = 0x1 OPCODE_BINARY = 0x2 OPCODE_CLOSE = 0x8 OPCODE_PING = 0x9 OPCODE_PONG = 0xa # available operation code value tuple OPCODES = (OPCODE_TEXT, OPCODE_BINARY, OPCODE_CLOSE, OPCODE_PING, OPCODE_PONG) # opcode human readable string OPCODE_MAP = { OPCODE_TEXT: "text", OPCODE_BINARY: "binary", OPCODE_CLOSE: "close", OPCODE_PING: "ping", OPCODE_PONG: "pong" } # data length threashold. LENGTH_7 = 0x7d LENGTH_16 = 1 << 16 LENGTH_63 = 1 << 63 def __init__(self, fin = 0, rsv1 = 0, rsv2 = 0, rsv3 = 0, opcode = OPCODE_TEXT, mask = 1, data = ""): """ Constructor for ABNF. please check RFC for arguments. """ self.fin = fin self.rsv1 = rsv1 self.rsv2 = rsv2 self.rsv3 = rsv3 self.opcode = opcode self.mask = mask self.data = data self.get_mask_key = os.urandom @staticmethod def create_frame(data, opcode): """ create frame to send text, binary and other data. data: data to send. This is string value(byte array). if opcode is OPCODE_TEXT and this value is uniocde, data value is conveted into unicode string, automatically. opcode: operation code. please see OPCODE_XXX. """ if opcode == ABNF.OPCODE_TEXT and isinstance(data, unicode): data = data.encode("utf-8") # mask must be set if send data from client return ABNF(1, 0, 0, 0, opcode, 1, data) def format(self): """ format this object to string(byte array) to send data to server. """ if not _is_bool(self.fin, self.rsv1, self.rsv2, self.rsv3): raise ValueError("not 0 or 1") if self.opcode not in ABNF.OPCODES: raise ValueError("Invalid OPCODE") length = len(self.data) if length >= ABNF.LENGTH_63: raise ValueError("data is too long") frame_header = chr(self.fin << 7 | self.rsv1 << 6 | self.rsv2 << 5 | self.rsv3 << 4 | self.opcode) if length < ABNF.LENGTH_7: frame_header += chr(self.mask << 7 | length) elif length < ABNF.LENGTH_16: frame_header += chr(self.mask << 7 | 0x7e) frame_header += struct.pack("!H", length) else: frame_header += chr(self.mask << 7 | 0x7f) frame_header += struct.pack("!Q", length) if not self.mask: return frame_header + self.data else: mask_key = self.get_mask_key(4) return frame_header + self._get_masked(mask_key) def _get_masked(self, mask_key): s = ABNF.mask(mask_key, self.data) return mask_key + "".join(s) @staticmethod def mask(mask_key, data): """ mask or unmask data. Just do xor for each byte mask_key: 4 byte string(byte). data: data to mask/unmask. """ _m = map(ord, mask_key) _d = map(ord, data) for i in range(len(_d)): _d[i] ^= _m[i % 4] s = map(chr, _d) return "".join(s) 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://echo.websocket.org") >>> ws.send("Hello, Server") >>> ws.recv() 'Hello, Server' >>> ws.close() get_mask_key: a callable to produce new mask keys, see the set_mask_key function's docstring for more details """ def __init__(self, get_mask_key = None): """ Initalize WebSocket object. """ self.connected = False self.io_sock = self.sock = socket.socket() self.get_mask_key = get_mask_key def set_mask_key(self, func): """ set function to create musk key. You can custumize mask key generator. Mainly, this is for testing purpose. func: callable object. the fuct must 1 argument as integer. The argument means length of mask key. This func must be return string(byte array), which length is argument specified. """ self.get_mask_key = func def settimeout(self, timeout): """ Set the timeout to the websocket. timeout: timeout time(second). """ self.sock.settimeout(timeout) def gettimeout(self): """ Get the websocket timeout(second). """ return self.sock.gettimeout() def connect(self, url, **options): """ Connect to url. url is websocket url scheme. ie. ws://host:port/resource You can customize using 'options'. If you set "header" dict object, you can set your own custom header. >>> ws = WebSocket() >>> ws.connect("ws://echo.websocket.org/", ... header={"User-Agent: MyProgram", ... "x-custom: header"}) timeout: socket timeout time. This value is integer. if you set None for this value, it means "use default_timeout value" options: current support option is only "header". if you set header as dict value, the custom HTTP headers are added. """ 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 = [] 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) key = _create_sec_websocket_key() headers.append("Sec-WebSocket-Key: %s" % key) headers.append("Sec-WebSocket-Version: %s" % VERSION) if "header" in options: headers.extend(options["header"]) headers.append("") headers.append("") 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 = self._validate_header(resp_headers, key) if not success: self.close() raise WebSocketException("Invalid WebSocket Header") self.connected = True def _validate_header(self, headers, key): for k, v in _HEADERS_TO_CHECK.iteritems(): r = headers.get(k, None) if not r: return False r = r.lower() if v != r: return False result = headers.get("sec-websocket-accept", None) if not result: return False result = result.lower() value = key + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" hashed = base64.encodestring(hashlib.sha1(value).digest()).strip().lower() return hashed == result 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, opcode = ABNF.OPCODE_TEXT): """ Send the data as string. payload: Payload must be utf-8 string or unicoce, if the opcode is OPCODE_TEXT. Otherwise, it must be string(byte array) opcode: operation code to send. Please see OPCODE_XXX. """ frame = ABNF.create_frame(payload, opcode) if self.get_mask_key: frame.get_mask_key = self.get_mask_key data = frame.format() self.io_sock.send(data) if traceEnabled: logger.debug("send: " + repr(data)) def ping(self, payload = ""): """ send ping data. payload: data payload to send server. """ self.send(payload, ABNF.OPCODE_PING) def pong(self, payload): """ send pong data. payload: data payload to send server. """ self.send(payload, ABNF.OPCODE_PONG) def recv(self): """ Receive string data(byte array) from the server. return value: string(byte array) value. """ opcode, data = self.recv_data() return data def recv_data(self): """ Recieve data with operation code. return value: tuple of operation code and string(byte array) value. """ while True: frame = self.recv_frame() if not frame: # handle error: # 'NoneType' object has no attribute 'opcode' raise WebSocketException("Not a valid frame %s" % frame) elif frame.opcode in (ABNF.OPCODE_TEXT, ABNF.OPCODE_BINARY): return (frame.opcode, frame.data) elif frame.opcode == ABNF.OPCODE_CLOSE: self.send_close() return (frame.opcode, None) elif frame.opcode == ABNF.OPCODE_PING: self.pong("Hi!") def recv_frame(self): """ recieve data as frame from server. return value: ABNF frame object. """ header_bytes = self._recv(2) if not header_bytes: return None b1 = ord(header_bytes[0]) fin = b1 >> 7 & 1 rsv1 = b1 >> 6 & 1 rsv2 = b1 >> 5 & 1 rsv3 = b1 >> 4 & 1 opcode = b1 & 0xf b2 = ord(header_bytes[1]) mask = b2 >> 7 & 1 length = b2 & 0x7f length_data = "" if length == 0x7e: length_data = self._recv(2) length = struct.unpack("!H", length_data)[0] elif length == 0x7f: length_data = self._recv(8) length = struct.unpack("!Q", length_data)[0] mask_key = "" if mask: mask_key = self._recv(4) data = self._recv_strict(length) if traceEnabled: recieved = header_bytes + length_data + mask_key + data logger.debug("recv: " + repr(recieved)) if mask: data = ABNF.mask(mask_key, data) frame = ABNF(fin, rsv1, rsv2, rsv3, opcode, mask, data) return frame def send_close(self, status = STATUS_NORMAL, reason = ""): """ send close data to the server. status: status code to send. see STATUS_XXX. reason: the reason to close. This must be string. """ if status < 0 or status >= ABNF.LENGTH_16: raise ValueError("code is invalid range") self.send(struct.pack('!H', status) + reason, ABNF.OPCODE_CLOSE) def close(self, status = STATUS_NORMAL, reason = ""): """ Close Websocket object status: status code to send. see STATUS_XXX. reason: the reason to close. This must be string. """ if self.connected: if status < 0 or status >= ABNF.LENGTH_16: raise ValueError("code is invalid range") try: self.send(struct.pack('!H', status) + reason, ABNF.OPCODE_CLOSE) timeout = self.sock.gettimeout() self.sock.settimeout(3) try: frame = self.recv_frame() if logger.isEnabledFor(logging.DEBUG): logger.error("close status: " + repr(frame.data)) 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 bytes == 0: raise WebSocketConnectionClosedException() 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, keep_running = True, get_mask_key = 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. keep_running: a boolean flag indicating whether the app's main loop should keep running, defaults to True get_mask_key: a callable to produce new mask keys, see the WebSocket.set_mask_key's docstring for more information """ self.url = url self.on_open = on_open self.on_message = on_message self.on_error = on_error self.on_close = on_close self.keep_running = keep_running self.get_mask_key = get_mask_key self.sock = None def send(self, data): """ send message. data must be utf-8 string or unicode. """ if self.sock.send(data) == 0: raise WebSocketConnectionClosedException() def close(self): """ close websocket connection. """ self.keep_running = False 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.get_mask_key) self.sock.connect(self.url) self._run_with_no_err(self.on_open) while self.keep_running: 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://echo.websocket.org/") print "Sending 'Hello, World'..." ws.send("Hello, World") print "Sent" print "Receiving..." result = ws.recv() print "Received '%s'" % result ws.close()