how can i use HttpResponse to response a file stream to download

[bouyeijiang]

i need to use file open stream to response the httpresponse download file.anybody give me a suggest?

[robjtede]

async fn handler(req: HttpRequest) -> impl Responder {
  let file = NamedFile::open_async("foo.txt").await.unwrap();
  let res: HttpResponse = file.into_response(&req);
  ...
}