BUG: plain HTTP request to a WebSocket route panics (unchecked type assertion + nil deref)

[junnhwan]

Bug description

A plain HTTP request to a route registered via app.WebSocket(...) reaches the WebSocket handler and can panic.

How it happens

App.WebSocket(route, handler) registers the route as a normal GET route:

• https://github.com/gofr-dev/gofr/blob/development/pkg/gofr/websocket.go#L30-L45

Inside the generated handler:

connID := ctx.Request.Context().Value(websocket.WSConnectionKey).(string)

conn := a.httpServer.ws.GetWebsocketConnection(connID)
if conn.Conn == nil {
    return nil, websocket.ErrorConnection
}

When a client sends a plain GET /ws (no Connection: Upgrade, no Upgrade: websocket headers), the WSHandlerUpgrade middleware does not add WSConnectionKey to the request context. The type assertion:

ctx.Request.Context().Value(websocket.WSConnectionKey).(string)

then panics with interface conversion: interface {} is nil, not string.

Even if that assertion were safe, GetWebsocketConnection("") returns nil, and the subsequent conn.Conn == nil would dereference nil.

Expected behavior

A non-WebSocket request to a WebSocket route should get a clean 4xx response (for example 400 Bad Request or websocket.ErrorConnection) instead of a panic.

Repro sketch

app := gofr.New()

app.WebSocket("/ws", func(ctx *gofr.Context) (any, error) {
    return "ok", nil
})

// Plain GET without WebSocket upgrade headers.
// expected: clean error response
// actual: panic

Suggested fix direction

In App.WebSocket handler, use a safe type assertion and nil checks before dereferencing:

connID, ok := ctx.Request.Context().Value(websocket.WSConnectionKey).(string)
if !ok {
    return nil, websocket.ErrorConnection
}

conn := a.httpServer.ws.GetWebsocketConnection(connID)
if conn == nil || conn.Conn == nil {
    return nil, websocket.ErrorConnection
}

Notes

• I did a quick search; I did not find an existing open issue/PR for this exact path.
• Related: Fix: Nil pointer panic in WriteMessageToSocket when WebSocket connection not found #3213 / Fix: Nil pointer panic in WriteMessageToSocket when WebSocket connection not found #3216 fixed WriteMessageToSocket nil panic, but this is a different code path (App.WebSocket route handler).