javascript - 如何将 Javascript 客户端连接到 Python-SocketIO 服务器？

Question

我刚刚开始使用 Python-SocketIO，我创建了一个示例服务器，它看起来像这样:

import eventlet
import socketio

sio = socketio.Server()

app = socketio.WSGIApp(sio, static_files={
    '/': {'content_type': 'text/html', 'filename': 'index.html'}
})

@sio.on('connect')
def connect(sid, environ):
    print('connect ', sid)

@sio.on('msg')
def message(sid, data):
    print('message ', data)

@sio.on('disconnect')
def disconnect(sid):
    print('disconnect ', sid)

if __name__ == '__main__':
    eventlet.wsgi.server(eventlet.listen(('', 5000)), app)

然后，我有一个在 Django 应用程序上运行的 HTML 文件，我想将该客户端连接到我的 Python-SocketIO 服务器:

<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/2.2.0/socket.io.js"></script>
<script>

socket = io.connect('');

socket.on('connect',function() {
  console.log('Client has connected to the server!');
});

socket.on('msg',function(data) {
  console.log('Received a message from the server!',data);
});

socket.on('disconnect',function() {
  console.log('The client has disconnected!');
});

// Sends a message to the server via sockets
function send(message) {
  socket.send('msg',message);
};

</script>

问题是，在我的客户端，我不断收到以下错误:

Access to XMLHttpRequest at 'http://localhost:5000/socket.io/?EIO=3&transport=polling&t=N5eSEa2' from origin 'http://127.0.0.1:8000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
localhost:5000/socket.io/?EIO=3&transport=polling&t=N5eSEa2:1 Failed to load resource: net::ERR_FAILED

我的 Django 服务器正在运行 on http://127.0.0.1:8000/ 。谁能帮我找出我做错了什么？

Answer 1

在服务器上设置 CORS header :

sio = socketio.Server(cors_allowed_origins='*')

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