how can i get the headers when using module-workers

export default {
  fetch(req: Request) {
    const someHeader = req.headers.get("some-header");
  }
}

export default {
  fetch(req: Request) {
    const someHeader = req.headers.get("some-header");
  }
}

export interface Env {
    BUCKET_URL_AUTH_GENERATION_KEY: string;
    BUCKET_URL_SYMMETRIC_KEY: string;
}

export default {
    async fetch(request: Request, env: Env,): Promise<Response> {
        if (!env.BUCKET_URL_AUTH_GENERATION_KEY || !env.BUCKET_URL_SYMMETRIC_KEY) {
            return new Response("Missing required environment variables", { status: 500 });
        }

export interface Env {
    BUCKET_URL_AUTH_GENERATION_KEY: string;
    BUCKET_URL_SYMMETRIC_KEY: string;
}

export default {
    async fetch(request: Request, env: Env,): Promise<Response> {
        if (!env.BUCKET_URL_AUTH_GENERATION_KEY || !env.BUCKET_URL_SYMMETRIC_KEY) {
            return new Response("Missing required environment variables", { status: 500 });
        }

const newRequest = new Request(request);

            const contentType = url.searchParams.get("content-type");
            if (contentType) {
                newRequest.headers.set("Content-Type", contentType);
            }
            
            const contentDisposition = url.searchParams.get("content-disposition");
            if (contentDisposition) {
                newRequest.headers.set("Content-Disposition", contentDisposition);
            }

            return fetch(new URL(url.pathname, `https://${requiredHostname}`), newRequest);

const newRequest = new Request(request);

            const contentType = url.searchParams.get("content-type");
            if (contentType) {
                newRequest.headers.set("Content-Type", contentType);
            }
            
            const contentDisposition = url.searchParams.get("content-disposition");
            if (contentDisposition) {
                newRequest.headers.set("Content-Disposition", contentDisposition);
            }

            return fetch(new URL(url.pathname, `https://${requiredHostname}`), newRequest);

const res = fetch(new URL(url.pathname, `https://${requiredHostname}`));

// Clone the response because it's immutable by default.
const clonedRes = new Response(res.body, res);
clonedRes.headers.set("Content-Disposition", contentDisposition);
clonedRes.headers.set("Content-Type", contentType);

return clonedRes

const res = fetch(new URL(url.pathname, `https://${requiredHostname}`));

// Clone the response because it's immutable by default.
const clonedRes = new Response(res.body, res);
clonedRes.headers.set("Content-Disposition", contentDisposition);
clonedRes.headers.set("Content-Type", contentType);

return clonedRes