websocket/ws_server.py at main · jiankaiwang/websocket · GitHub

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#!/usr/bin/env python
# -*- coding:utf-8 -*-

"""
Simple WebSocket Server
"""

import socket
import base64
import hashlib


def get_headers(data):
  """Transform the headers into the dictionary."""
  header_dict = {}
  data = str(data, encoding='utf-8')

  header, body = data.split('\r\n\r\n', 1)
  header_list = header.split('\r\n')
  for i in range(0, len(header_list)):
    if i == 0:
      if len(header_list[i].split(' ')) == 3:
        header_dict['method'], header_dict['url'], header_dict['protocol'] = header_list[i].split(' ')
    else:
      k, v = header_list[i].split(':', 1)
      header_dict[k] = v.strip()
  print("Headers: {}".format(header_dict))
  return header_dict


def send_msg(conn, msg_bytes):
  """
  WebSocket's message to clients

  Args:
    conn: conn, address = socket.accept()
    msg_bytes: message to the client
  """
  import struct

  token = b"\x81"
  length = len(msg_bytes)
  if length < 126:
    token += struct.pack("B", length)
  elif length <= 0xFFFF:
    token += struct.pack("!BH", 126, length)
  else:
    token += struct.pack("!BQ", 127, length)

  msg = token + msg_bytes
  conn.send(msg)


def run():
  sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
  sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
  sock.bind(('127.0.0.1', 8003))
  sock.listen(5)

  conn, address = sock.accept()
  data = conn.recv(1024)
  headers = get_headers(data)
  response_tpl = "HTTP/1.1 101 Switching Protocols\r\n" \
           "Upgrade:websocket\r\n" \
           "Connection:Upgrade\r\n" \
           "Sec-WebSocket-Accept:%s\r\n" \
           "WebSocket-Location:ws://%s%s\r\n\r\n"

  value = headers['Sec-WebSocket-Key'] + '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
  ac = base64.b64encode(hashlib.sha1(value.encode('utf-8')).digest())
  response_str = response_tpl % (ac.decode('utf-8'), headers['Host'], headers['url'])
  conn.send(bytes(response_str, encoding='utf-8'))

  while True:
    try:
      info = conn.recv(8096)
    except Exception as e:
      info = None
    if not info:
      break
    payload_len = info[1] & 127
    if payload_len == 126:
      extend_payload_len = info[2:4]
      mask = info[4:8]
      decoded = info[8:]
    elif payload_len == 127:
      extend_payload_len = info[2:10]
      mask = info[10:14]
      decoded = info[14:]
    else:
      extend_payload_len = None
      mask = info[2:6]
      decoded = info[6:]

    bytes_list = bytearray()
    for i in range(len(decoded)):
      chunk = decoded[i] ^ mask[i % 4]
      bytes_list.append(chunk)


    if bytes_list != b'\x03\xe9':
      message = str(bytes_list, encoding='utf-8')
      body = "'" + message + "' (from the server)"
      if message == "_state_closing":
        print("Closed the connection from the client.")
        break
      else:
        send_msg(conn,body.encode('utf-8'))
    else:
      print("No message or empty message from the client.")

  sock.close()

if __name__ == '__main__':
  run()