1.目前有一个Python实现的Websocket服务器，它可以在一台机器上运行，但当连接数量增加时，服务器的性能会下降。需要改进代码以支持多线程，使服务器能够利用机器上的所有处理器内核，提高服务器的性能。
- 解决方案:
为了提高服务器的性能，可以使用多线程来处理不同的客户端连接。具体做法是，把
WebSocketServer类修改成如下这样：
class WebSocketServer:
def __init__(self, host, port, limit, **kwargs):
"""
Initialize websocket server.
:param host: Host name as IP address or text definition.
:param port: Port number, which server will listen.
:param limit: Limit of connections in queue.
:param kwargs: A dict of key/value pairs. It MAY contains:<br>
<b>onconnect</b> - function, called after client connected.
<b>handshake</b> - string, containing the handshake pattern.
<b>magic</b> - string, containing "magic" key, required for "handshake".
:type host: str
:type port: int
:type limit: int
:type kwargs: dict
"""
self.host = host
self.port = port
self.limit = limit
self.running = False
self.clients = []
self.args = kwargs
self.lock = threading.Lock()
def start(self):
"""
Start websocket server.
"""
self.root = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.root.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.root.bind((self.host, self.port))
self.root.listen(self.limit)
self.running = True
while self.running:
client, address = self.root.accept()
if not self.running: break
self.handshake(client)
self.lock.acquire()
self.clients.append((client, address))
self.lock.release()
onconnect = self.args.get("onconnect")
if callable(onconnect): onconnect(self, client, address)
threading.Thread(target=self.loop, args=(client, address)).start()
self.root.close()
def stop(self):
"""
Stop websocket server.
"""
self.running = False
def handshake(self, client):
handshake = 'HTTP/1.1 101 Switching Protocols\r\nConnection: Upgrade\r\nUpgrade: websocket\r\nSec-WebSocket-Accept: %s\r\n\r\n'
handshake = self.args.get('handshake', handshake)
magic = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
magic = self.args.get('magic', magic)
header = str(client.recv(1000))
try:
res = header.index("Sec-WebSocket-Key")
except ValueError:
return False
key = header[res + 19: res + 19 + 24]
key += magic
key = hashlib.sha1(key.encode())
key = base64.b64encode(key.digest())
client.send(bytes((handshake % str(key,'utf-8')), 'utf-8'))
return True
def loop(self, client, address):
"""
:type client: socket
"""
while True:
message = ''
m = client.recv(1)
while m != '':
message += m
m = client.recv(1)
fin, text = self.decodeFrame(message)
if not fin:
onmessage = self.args.get('onmessage')
if callable(onmessage): onmessage(self, client, text)
else:
self.lock.acquire()
self.clients.remove((client, address))
self.lock.release()
ondisconnect = self.args.get('ondisconnect')
if callable(ondisconnect): ondisconnect(self, client, address)
client.close()
break
def decodeFrame(self, data):
if (len(data) == 0) or (data is None):
return True, None
fin = not(data[0] & 1)
if fin:
return fin, None
masked = not(data[1] & 1)
plen = data[1] - (128 if masked else 0)
mask_start = 2
if plen == 126:
mask_start = 4
plen = int.from_bytes(data[2:4], byteorder='sys.byteorder')
elif plen == 127:
mask_start = 10
plen = int.from_bytes(data[2:10], byteorder='sys.byteorder')
mask = data[mask_start:mask_start+4]
data = data[mask_start+4:mask_start+4+plen]
decoded = []
i = 0
while i < len(data):
decoded.append(data[i] ^ mask[i%4])
i+=1
text = str(bytearray(decoded), "utf-8")
return fin, text
def sendto(self, client, data, **kwargs):
"""
Send <b>data</b> to <b>client</b>. <b>data</b> can be of type <i>str</i>, <i>bytes</i>, <i>bytearray</i>, <i>int</i>.
:param client: Client socket for data exchange.
:param data: Data, which will be sent to the client via <i>socket</i>.
:type client: socket
:type data: str|bytes|bytearray|int|float
"""
if type(data) == bytes or type(data) == bytearray:
frame = data
elif type(data) == str:
frame = bytes(data, kwargs.get('encoding', 'utf-8'))
elif type(data) == int or type(data) == float:
frame = bytes(str(data), kwargs.get('encoding', 'utf-8'))
else:
return None
framelen = len(frame)
head = bytes([0x81])
if framelen < 126:
head += bytes(int.to_bytes(framelen, 1, 'big'))
elif 126 <= framelen < 0x10000:
head += bytes(126)
head += bytes(int.to_bytes(framelen, 2, 'big'))
else:
head += bytes(127)
head += bytes(int.to_bytes(framelen, 8, 'big'))
client.send(head + frame)
通过使用多线程，服务器可以同时处理多个客户端连接，从而提高服务器的性能。
此外，在WebSocketServer类中添加了一个lock对象，用于对clients列表进行加锁，以避免多线程同时访问clients列表时产生数据不一致的情况。
