一. 客戶端服務端進行握手
1.客戶端向服務端傳送握手包
GET ws://localhost:8000/ HTTP/1.1
Host: localhost:8000
Connection: Upgrade
Pragma: no-cache
Cache-Control: no-cache
Upgrade: websocket
Origin: http://localhost:63342
Sec-WebSocket-Version: 13
Accept-Encoding: gzip, deflate, sdch, br
Accept-Language: zh-CN,zh;q=0.8
Sec-WebSocket-Key: 60jj9YDlrvPB+DzLmVJzcg==
Sec-WebSocket-Extensions: permessage-deflate; client_max_window_bits複製程式碼2.服務端進行迴應,返回給客戶端
HTTP/1.1 101 Switching Protocols
Upgrade: WebSocket
Connection: Upgrade
Sec-WebSocket-Accept: Cx7gYudkmGmF8rMFP1W1HbLkWRA=複製程式碼客戶端傳送握手請求，然後服務端返回正確的資料，經過客戶端的確認完成握手，然後就可以進行通訊了；
這裡客戶端傳送的Sec-WebSocket-Key是一個Base64 encode的值，它是瀏覽器隨機生成的，然後服務端通過這個值生成一個Sec-WebSocket-Accept;
方法： key+'258EAFA5-E914-47DA-95CA-C5AB0DC85B11'，然後SHA-1加密，再進行base-64加密；
下面是握手程式碼：
HANDSHAKE_STR = (
"HTTP/1.1 101 Switching Protocols\r\n"
"Upgrade: WebSocket\r\n"
"Connection: Upgrade\r\n"
"Sec-WebSocket-Accept: %(token)s\r\n\r\n"
)
GUID_STR = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
def parseHeaders(self, msg):
# print(msg)
headers = {}
msg = str(msg, encoding="utf-8")
header, data = msg.split('\r\n\r\n', 1)
for x in header.split("\r\n")[1:]:
# 這裡是 “:+space”
key, value = x.split(": ", 1)
headers[key] = value
return headers
# 握手資料
def handShakeData(self,c_req):
sec_key = self.parseHeaders(c_req)['Sec-WebSocket-Key']
key = sec_key.encode("ascii") + GUID_STR.encode("ascii")
accept_token = base64.b64encode(hashlib.sha1(key).digest()).decode("ascii")
s_res = HANDSHAKE_STR % {'token': accept_token}
return s_res複製程式碼二. 進行通訊
大概就是握手完成後，客戶端傳送訊息到服務端，然後服務端將訊息傳送到每個連線上的客戶端；
資料互動協議
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-------+-+-------------+-------------------------------+
|F|R|R|R| opcode|M| Payload len | Extended payload length |
|I|S|S|S| (4) |A| (7) | (16/64) |
|N|V|V|V| |S| | (if payload len==126/127) |
| |1|2|3| |K| | |
+-+-+-+-+-------+-+-------------+ - - - - - - - - - - - - - - - +
| Extended payload length continued, if payload len == 127 |
+ - - - - - - - - - - - - - - - +-------------------------------+
| |Masking-key, if MASK set to 1 |
+-------------------------------+-------------------------------+
| Masking-key (continued) | Payload Data |
+-------------------------------- - - - - - - - - - - - - - - - +
: Payload Data continued ... :
+ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +
| Payload Data continued ... |
+---------------------------------------------------------------+複製程式碼第一個位元組：
- FIN：描述訊息是否結束；佔1bit；如果是1表示這是資料包的最後一幀，0則表示後續還有資料；
- RSV1, RSV2, RSV3：擴充套件定義，預設0，各佔1bit;
- opcode：表示傳輸的資料包型別，佔4bit,(15種情況)
0x0表示為附加資料0x1表示為text型別資料0x2表示binary型別資料0x3~7暫未定義0x8表示連線關閉0x9表示ping型別資料0xA表示pong型別資料0xB~F暫未定義
第二個位元組：
- MASK：表示是否經過掩碼處理；如果是1，表示經過掩碼處理，Masking-key的資料為掩碼密碼
- Payload length：
- 如果值為0~125，則就是payload的真實長度；（若MASK=1,則Masking-key為第3~6個位元組）
- 如果值為126，則後面的2個位元組（16bit）為payload的真實長度；（若MASK=1,則Masking-key為第5~8個位元組）
- 如果值為127，則後面的8個位元組（64bit）為payload的真實長度；（若MASK=1,則Masking-key為第11~14個位元組）
1. 將客戶端傳送的資料解析出真實的資料
方法：將Payload Data資料的每一位x,與Masking-key的第i%4位進行異或運算，i是x在Payload Data中的索引；
下面是解析的程式碼：
def parseData(self,msg):
g_code_length = msg[1] & 127
if g_code_length == 126:
g_code_length = struct.unpack('!H', msg[2:4])[0]
masks = msg[4:8]
data = msg[8:]
elif g_code_length == 127:
g_code_length = struct.unpack('!Q', msg[2:10])[0]
masks = msg[10:14]
data = msg[14:]
else:
masks = msg[2:6]
data = msg[6:]
i = 0
raw_by = bytearray()
for d in data:
raw_by.append( int(d) ^ int(masks[i % 4]) )
i += 1
print(u"總長度是：%d" % int(g_code_length))
raw_str = raw_by.decode()
return raw_str複製程式碼2. 將資料傳送到客戶端
傳送的資料格式：固定位元組+包長度位元組+原始資料
例：\x81\x0cHello World!
三. 完整的程式碼
服務端：
import socket
import base64,hashlib
import threading
import struct
from collections import deque
HANDSHAKE_STR = (
"HTTP/1.1 101 Switching Protocols\r\n"
"Upgrade: WebSocket\r\n"
"Connection: Upgrade\r\n"
"Sec-WebSocket-Accept: %(token)s\r\n\r\n"
)
GUID_STR = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11'
STREAM = 0x0
TEXT = 0x1
BINARY = 0x2
CLOSE = 0x8
PING = 0x9
PONG = 0xA
class WebSocket(threading.Thread):
def __init__(self,conn,addr,index):
threading.Thread.__init__(self)
self.index = index
self.conn = conn
self.addr = addr
#傳送的資料快取
self.buffer = bytearray()
self.sendToClientData = deque()
# 組裝header 獲取‘Sec-WebSocket-Key’
def parseHeaders(self, msg):
# print(msg)
headers = {}
msg = str(msg, encoding="utf-8")
header, data = msg.split('\r\n\r\n', 1)
for x in header.split("\r\n")[1:]:
# 這裡是 “:+space”
key, value = x.split(": ", 1)
headers[key] = value
return headers
# 握手資料
def handShakeData(self,c_req):
sec_key = self.parseHeaders(c_req)['Sec-WebSocket-Key']
key = sec_key.encode("ascii") + GUID_STR.encode("ascii")
accept_token = base64.b64encode(hashlib.sha1(key).digest()).decode("ascii")
s_res = HANDSHAKE_STR % {'token': accept_token}
return s_res
# 得到資料長度 （包含描述位元組）
def getMsglen(self,msg):
g_code_length = msg[1] & 127
if g_code_length == 126:
g_code_length = struct.unpack('!H', msg[2:4])[0]
g_code_length += 8
elif g_code_length == 127:
g_code_length = struct.unpack('!Q', msg[2:10])[0]
g_code_length += 14
else:
g_code_length += 6
g_code_length = int(g_code_length)
print(g_code_length)
return g_code_length
# 解析資料
def parseData(self,msg):
g_code_length = msg[1] & 127
if g_code_length == 126:
g_code_length = struct.unpack('!H', msg[2:4])[0]
masks = msg[4:8]
data = msg[8:]
elif g_code_length == 127:
g_code_length = struct.unpack('!Q', msg[2:10])[0]
masks = msg[10:14]
data = msg[14:]
else:
masks = msg[2:6]
data = msg[6:]
i = 0
raw_by = bytearray()
for d in data:
raw_by.append( int(d) ^ int(masks[i % 4]) )
i += 1
print(raw_by)
print(u"總長度是：%d" % int(g_code_length))
raw_str = raw_by.decode()
# raw_str = str(raw_by)
return raw_str
# 傳送訊息
def sendMessage(self,message):
# 遍歷連線上的列表
for conn in connections.values():
# 傳送訊息到client （除了自己）
if conn != self.conn:
self._sendMessage(False,TEXT,message)
while self.sendToClientData:
data = self.sendToClientData.popleft()
conn.send(data[1])
# FIN 後面是否還有資料；opcode 傳輸的資料包型別；message 傳輸的資料(str)
def _sendMessage(self,FIN,opcode,message):
payload = bytearray()
b1 = 0
b2 = 0
if FIN is False:
b1 |= 0x80
b1 |= opcode # 若opcode=TEXT b'0x81'
payload.append(b1) #
msg_utf = message.encode('utf-8')
msg_len = len(msg_utf)
if msg_len <= 125:
b2 |= msg_len
payload.append(b2)
elif msg_len >= 126 and msg_len <= 65535:
b2 |= 126
payload.append(b2)
payload.extend(struct.pack("!H", msg_len))
elif msg_len <= (2 ^ 64 - 1):
b2 |= 127
payload.append(b2)
payload.extend(struct.pack("!Q", msg_len))
else:
print("傳輸的資料太長了! ——(_sendMessage)")
# 拼接上需要傳送的資料
# 格式大概這樣：bytearray(b'\x81\x0cHello World!') '\x0c'是傳送的資料長度
if msg_len > 0:
payload.extend(msg_utf)
self.sendToClientData.append((opcode,payload))
# 端開連線
def _disConnected(self):
self.conn.close()
print("斷開的連線conn%s" % (self.index))
print(connections)
del connections['conn%s' % (self.index)]
print(connections)
#
def run(self):
# print(self.listeners)
self.isHandShake = False
while True:
if self.isHandShake == False:
print("start handshake %s" % (self.addr[0]))
# 接收客戶端內容
c_req = self.conn.recv(1024)
# print(c_req)
handData = self.handShakeData(c_req)
self.conn.sendall(str.encode(handData))
self.isHandShake = True
else:
message = self.conn.recv(16384) # 16 * 1024 16384 # bytes
print(message)
# 斷開連線
if message[0]&127 == CLOSE: # 0x88 136
self._disConnected()
return
self.buffer.extend(message) # bytes
code_length = self.getMsglen(self.buffer) # 資料中帶的 資料長度（包含描述位元組）
# 資料完整就傳送
if code_length == len(self.buffer):
buffer_utf = self.parseData(self.buffer) # str
self.sendMessage(buffer_utf)
print(message)
self.buffer = bytearray()
connections = {}
class websocketServer(object):
def __init__(self,host, port):
self.serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.serversocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.serversocket.bind((host, port))
self.serversocket.listen(5)
def server(self):
print(self.serversocket)
index =0
while True:
conn,addr = self.serversocket.accept()
print(conn)
print(addr)
# 新建執行緒
newSocket = WebSocket(conn,addr,index)
# 開始執行緒,執行run函式
newSocket.start()
connections['conn%s'% (index)] = conn
index += 1
print(connections)
websocketServer = websocketServer("127.0.0.1",8000)
websocketServer.server()複製程式碼感謝您的閱讀；