socket、socketio、flask-socketio、WebSocket的区别与联系
总结
HTTP、WebSocket 等应用层协议，都是基于 TCP 协议来传输数据的。我们可以把这些高级协议理解成对 TCP 的封装。
既然大家都使用 TCP 协议，那么大家的连接和断开，都要遵循 TCP 协议中的三次握手和四次挥手，只是在连接之后发送的内容不同，或者是断开的时间不同。
对于 WebSocket 来说，它必须依赖 HTTP 协议进行一次握手 ，握手成功后，数据就直接从 TCP 通道传输，与 HTTP 无关了。
在源码flask_socketio.SocketIO#run方法中可以看出 select 多路复用的几种选择。
if self.server.eio.async_mode == ‘threading‘:
from werkzeug._internal import _log
_log(‘warning‘, ‘WebSocket transport not available. Install ‘
‘eventlet or gevent and gevent-websocket for ‘
‘improved performance.‘)
app.run(host=host, port=port, threaded=True,
use_reloader=use_reloader, **kwargs)
# 这里的 app 就是 app = Flask(__name__)
elif self.server.eio.async_mode == ‘eventlet‘:
def run_server():
import eventlet
import eventlet.wsgi
import eventlet.green
addresses = eventlet.green.socket.getaddrinfo(host, port)
if not addresses:
raise RuntimeError(‘Could not resolve host to a valid address‘)
eventlet_socket = eventlet.listen(addresses[0][4], addresses[0][0])
# If provided an SSL argument, use an SSL socket
ssl_args = [‘keyfile‘, ‘certfile‘, ‘server_side‘, ‘cert_reqs‘,
‘ssl_version‘, ‘ca_certs‘,
‘do_handshake_on_connect‘, ‘suppress_ragged_eofs‘,
‘ciphers‘]
ssl_params = {k: kwargs[k] for k in kwargs if k in ssl_args}
if len(ssl_params) > 0:
for k in ssl_params:
kwargs.pop(k)
ssl_params[‘server_side‘] = True # Listening requires true
eventlet_socket = eventlet.wrap_ssl(eventlet_socket,
**ssl_params)
eventlet.wsgi.server(eventlet_socket, app,
log_output=log_output, **kwargs)
if use_reloader:
run_with_reloader(run_server, extra_files=extra_files)
else:
run_server()
elif self.server.eio.async_mode == ‘gevent‘:
from gevent import pywsgi
try:
from geventwebsocket.handler import WebSocketHandler
websocket = True
except ImportError:
websocket = False
https://www.cnblogs.com/minsons/p/8251780.html
http://python-socketio.readthedocs.io/en/latest/
https://www.cnblogs.com/lgjbky/p/9391073.html
python中socket、socketio、flask-socketio、WebSocket的区别与联系
原文：https://www.cnblogs.com/a-ant/p/10952417.html