给flask添加WebSocket
方案选取
flask目前有两个较为广为流传的方案：Flask-SocketIO 和 Flask-Sockets，其中Flask-SocketIO封装得比较多，但是它自己用http轮询封装了一个新的协议来实现websocket功能，前端需要加载一个js库来实现，如果要实现原生浏览器websocket会有较多的坑要填。
另外，一般情况下我们需要用websocket就是不想用轮询，结果你又给我用轮询封装，感觉有点多此一举。
所以
我选择了Flask-Sockets
集成到 app
from flask import Flask
from flask_sockets import Sockets
app = Flask(__name__)
sockets = Sockets(app)
@sockets.route('/echo')
def echo_socket(ws):
while not ws.closed:
message = ws.receive()
ws.send(message)
@app.route('/')
def hello():
return 'Hello World!'
if __name__ == "__main__":
from gevent import pywsgi
from geventwebsocket.handler import WebSocketHandler
server = pywsgi.WSGIServer(('', 5000), app, handler_class=WebSocketHandler)
server.serve_forever()
集成到蓝图 buleprint
from flask import Flask, Blueprint
from flask_sockets import Sockets
html = Blueprint(r'html', __name__)
ws = Blueprint(r'ws', __name__)
@html.route('/')
def hello():
return 'Hello World!'
@ws.route('/echo')
def echo_socket(socket):
while not socket.closed:
message = socket.receive()
socket.send(message)
app = Flask(__name__)
sockets = Sockets(app)
app.register_blueprint(html, url_prefix=r'/')
sockets.register_blueprint(ws, url_prefix=r'/') # 注册蓝图到sockets
if __name__ == "__main__":
from gevent import pywsgi
from geventwebsocket.handler import WebSocketHandler
server = pywsgi.WSGIServer(('', 5000), app, handler_class=WebSocketHandler)
server.serve_forever()
改良
@sse.route('/echo')
def echo_socket(socket):
# print('socket.closed:',not socket.closed)
# env = request.environ.get('wsgi.websocket')
# print(dir(socket), '---->')
# print(dir(socket.handler),'<<><><><><')
# print(socket.handler.active_client)
# a = socket.handler.active_client
部署
Flask-Sockets集成了gunicorn的部署支持，很方便
gunicorn -k flask_sockets.worker manage:app -c gunicorn.conf
使用 -k 参数指定 flask_sockets.worker 作为worker或者直接在gunicorn.conf里配置上
worker_class="flask_sockets.worker"