simple-websocket-server

A simple WebSocket server

Based on simple-websocket-server.

• RFC 6455 (All latest browsers)
• TLS/SSL out of the box
• Passes Autobahns Websocket Testsuite
• Support for Python 2 and 3

Installation

pip install simple-websocket-server

Echo Server Example

from simple_websocket_server import WebSocketServer, WebSocket


class SimpleEcho(WebSocket):
    def handle(self):
        # echo message back to client
        self.send_message(self.data)

    def connected(self):
        print(self.address, 'connected')

    def handle_close(self):
        print(self.address, 'closed')


server = WebSocketServer('', 8000, SimpleEcho)
server.serve_forever()

Open tests/websocket.html and connect to the server.

Chat Server Example

from simple_websocket_server import WebSocketServer, WebSocket


class SimpleChat(WebSocket):
    def handle(self):
        for client in clients:
            if client != self:
                client.send_message(self.address[0] + u' - ' + self.data)

    def connected(self):
        print(self.address, 'connected')
        for client in clients:
            client.send_message(self.address[0] + u' - connected')
        clients.append(self)

    def handle_close(self):
        clients.remove(self)
        print(self.address, 'closed')
        for client in clients:
            client.send_message(self.address[0] + u' - disconnected')


clients = []

server = WebSocketServer('', 8000, SimpleChat)
server.serve_forever()

Open multiple tests/websocket.html and connect to the server.

Want to get up and running faster?

There is an example which provides a simple echo and chat server

Echo Server

python tests/example_server.py --example echo

Chat Server (open up multiple tests/websocket.html files)

python tests/example_server.py --example chat

TLS/SSL Example

1. Generate a certificate with key

    openssl req -new -x509 -days 365 -nodes -out cert.pem -keyout key.pem
   

2. Run the secure TLS/SSL server (in this case the cert.pem file is in the same directory)

    python tests/example_server.py --example chat --ssl 1
   

3. Offer the certificate to the browser by serving tests/websocket.html through https. The HTTPS server will look for cert.pem in the local directory. Ensure the tests/websocket.html is also in the same directory to where the server is run.

    python tests/simple_https_server.py
   

4. Open a web browser to: https://localhost:443/tests/websocket.html

5. Change ws://localhost:8000/ to wss://localhost:8000 and click connect.

Note: if you are having problems connecting, ensure that the certificate is added in your browser against the exception https://localhost:8000 or whatever host:port pair you want to connect to.

For the Programmers

connected: called when handshake is complete

• self.address: TCP address port tuple of the endpoint

handle_close: called when the endpoint is closed or there is an error

• self.address: TCP address port tuple of the endpoint

handle: gets called when there is an incoming message from the client endpoint

• self.address: TCP address port tuple of the endpoint
• self.opcode: the WebSocket frame type (STREAM, TEXT, BINARY)
• self.data: bytearray (BINARY frame) or unicode string payload (TEXT frame)
• self.request: HTTP details from the WebSocket handshake (refer to BaseHTTPRequestHandler)

send_message: send some text or binary data to the client endpoint

• sending data as a unicode object will send a TEXT frame
• sending data as a bytearray object will send a BINARY frame

close: send close frame to endpoint

Licensing

MIT