content: """
  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
  try:
      import ssl
  except ImportError:
      pass
  
  from urllib.parse import urlparse
  import os
  import array
  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.
      """
      sockopt = options.get("sockopt", ())
      websock = WebSocket(sockopt=sockopt)
      websock.settimeout(timeout != None and timeout or default_timeout)
      websock.connect(url, **options)
      return websock
  
  _MAX_INTEGER = (1 << 32) -1
  _AVAILABLE_KEY_CHARS = list(range(0x21, 0x2f + 1)) + list(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.encodebytes(uid.bytes).strip().decode("utf-8")
  
  _HEADERS_TO_CHECK = {
      "upgrade": "websocket",
      "connection": "upgrade",
      }
  
  
  class _SSLSocketWrapper(object):
      def __init__(self, sock):
          self._ssl = ssl.wrap_socket(sock)
  
      def recv(self, bufsize):
          return self._ssl.read(bufsize)
  
      def send(self, payload):
          return self._ssl.write(payload)
  
      def close(self):
          self._ssl.close()
  
  _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, str):
              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 = []
          frame_header = bytes((self.fin << 7
                             | self.rsv1 << 6 | self.rsv2 << 5 | self.rsv3 << 4
                             | self.opcode,))
          if length < ABNF.LENGTH_7:
              frame_header += bytes((self.mask << 7 | length,))
          elif length < ABNF.LENGTH_16:
              frame_header += bytes((self.mask << 7 | 0x7e,))
              frame_header += struct.pack("!H", length)
          else:
              frame_header += bytes((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 + 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 = array.array("B", mask_key)
          _d = array.array("B", data)
          for i in range(len(_d)):
              _d[i] ^= _m[i % 4]
  
          return _d.tobytes()
  
  
  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
      sockopt: values for socket.setsockopt.
          sockopt must be tuple and each element is argument of sock.setscokopt.
      """
  
      def __init__(self, get_mask_key = None, sockopt = ()):
          """
          Initalize WebSocket object.
          """
          self.connected = False
          self.sock = socket.socket()
          for opts in sockopt:
              self.sock.setsockopt(*opts)
          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.sock = _SSLSocketWrapper(self.sock)
          self._handshake(hostname, port, resource, **options)
  
      def _handshake(self, host, port, resource, **options):
          sock = self.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)
  
          if "origin" in options:
              headers.append("Origin: %s" % options["origin"])
          else:
              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(bytes(header_str, "utf-8"))
          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.items():
              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"
          digest = hashlib.sha1(bytes(value, "utf-8")).digest()
          hashed = base64.encodebytes(digest).strip().decode("utf-8").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 bytes or str,
                    if the opcode is OPCODE_TEXT.
                    Otherwise, it must be byte array
  
          opcode: operation code to send. Please see OPCODE_XXX.
          """
          if isinstance(payload, str):
              payload = bytes(payload, "utf-8")
          frame = ABNF.create_frame(payload, opcode)
          if self.get_mask_key:
              frame.get_mask_key = self.get_mask_key
          data = frame.format()
          while data:
              l = self.sock.send(data)
              data = data[l:]
          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()
          if opcode == ABNF.OPCODE_TEXT:
              return data.decode("utf-8")
          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(frame.data)
  
      def recv_frame(self):
          """
          recieve data as frame from server.
  
          return value: ABNF frame object.
          """
          header_bytes = self._recv_strict(2)
          if not header_bytes:
              return None
          b1 = header_bytes[0]
          fin = b1 >> 7 & 1
          rsv1 = b1 >> 6 & 1
          rsv2 = b1 >> 5 & 1
          rsv3 = b1 >> 4 & 1
          opcode = b1 & 0xf
          b2 = header_bytes[1]
          mask = b2 >> 7 & 1
          length = b2 & 0x7f
  
          length_data = b""
          if length == 0x7e:
              length_data = self._recv_strict(2)
              length = struct.unpack("!H", length_data)[0]
          elif length == 0x7f:
              length_data = self._recv_strict(8)
              length = struct.unpack("!Q", length_data)[0]
  
          mask_key = b""
          if mask:
              mask_key = self._recv_strict(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()
  
      def _recv(self, bufsize):
          bytes = self.sock.recv(bufsize)
          if not bytes:
              raise WebSocketConnectionClosedException()
          return bytes
  
      def _recv_strict(self, bufsize):
          remaining = bufsize
          bytes = b""
          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 == b"\n":
                  break
          return b"".join(line).decode("utf-8")
  
  
  class WebSocketApp(object):
      """
      Higher level of APIs are provided.
      The interface is like JavaScript WebSocket object.
      """
      def __init__(self, url, header = [],
                   on_open = None, on_message = None, on_error = None,
                   on_close = None, keep_running = True, get_mask_key = None,
                   sockopt=()):
          """
          url: websocket url.
          header: custom header for websocket handshake.
          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.header = header
          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, opcode = ABNF.OPCODE_TEXT):
          """
          send message.
          data: message to send. If you set opcode to OPCODE_TEXT, data must be utf-8 string or unicode.
          opcode: operation code of data. default is OPCODE_TEXT.
          """
          if self.sock.send(data, opcode) == 0:
              raise WebSocketConnectionClosedException()
  
      def close(self):
          """
          close websocket connection.
          """
          self.keep_running = False
          self.sock.close()
  
      def run_forever(self, sockopt=()):
          """
          run event loop for WebSocket framework.
          This loop is infinite loop and is alive during websocket is available.
          sockopt: values for socket.setsockopt.
              sockopt must be tuple and each element is argument of sock.setscokopt.
          """
          if self.sock:
              raise WebSocketException("socket is already opened")
          try:
              self.sock = WebSocket(self.get_mask_key, sockopt = sockopt)
              self.sock.connect(self.url, header = self.header)
              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 as 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 as 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()