How to send dummy request for spying on method inside http.createServer listner?

Question

I have a method as follows -

// A.ts
export abstract class A{
    protected abstract method();
}

//B.ts
export class B extends A{
    private _httpServer?: http.Server;
    private _wsServer?: WebSocketServer;
    constructor(){  super();  }

    protected async method(){
        init();
        //some more method calls
    }

    private async init(){
        this._httpServer = http.createServer(async (request, response) => {
            if(something){
                response.writeHead(statusCode, { 'Content-Type': 'text/plain' });
                response.end();
            }
            else{
                response.end("success")
            }
        })
        this._httpServer.on('error', error => console.log(error));
        this._httpServer.listen(8080);
        this._wsServer = new WebSocketServer({ noServer: true, path: '/ws' });
    }
    
}

I want to write tests for init() method. For that I want dummy request to sent so that I can enter inside createServer method and spy on inside codes to increase coverage. How can I do that?