How Can HTTP Middleware Secure WebSocket Connections in Golang?

Authenticating WebSocket Connections via HTTP Middleware

WebSocket connections provide a means of real-time communication between clients and servers. However, unlike HTTP requests, WebSockets do not inherently support authorization or authentication. To address this, HTTP middleware can be used to secure WebSocket connections.

Problem Statement

One common approach is to authenticate the upgrade handshake using the application's code for authenticating HTTP requests. However, implementing this approach in Golang using Gorilla's WebSocket upgrader has proven challenging.

Community Suggestions

Some community suggestions include:

• Check the username and password after the connection is established (non-idiomatic)

Failed Strategy

The failed strategy involved adding a custom header ("X-Api-Key") to the initial HTTP GET request and only upgrading clients with a matching key. However, this resulted in the client failing to utilize the WebSocket protocol with an 'upgrade' token not found error on the server.

Improved Solution for Strategy 1

To improve strategy 1, the authentication should be performed on the WebSocket handshake itself. This can be achieved by passing the authentication headers as the last argument to Dial in the client code.

<br>func main() {</p>
<div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false">u := url.URL{Scheme: "ws", Host: "localhost:8080", Path: "/ws"}
headers := http.Header{"X-Api-Key": []string{"test_api_key"}}
conn, _, err := websocket.DefaultDialer.Dial(u.String(), headers)
if err != nil {
    log.Fatalf("dial err: %v", err)
}