from a stream "FramedRead" how to "do something" in every chunk - rust

Question

I would like to display the upload progress of a file using the crate indicatif, I am uploading the file asynchronous using reqwest with something like this:
use tokio::fs::File;
use tokio_util::codec::{BytesCodec, FramedRead};
let file = File::open(file_path).await?;
let stream = FramedRead::new(file, BytesCodec::new());
let body = Body::wrap_stream(stream);
client.put(url).body(body)
The progress bar is implemented like this:
use indicatif::ProgressBar;
let bar = ProgressBar::new(1000);
for _ in 0..1000 {
bar.inc(1);
// ...
}
bar.finish();
How from the stream:
let stream = FramedRead::new(file, BytesCodec::new());
// how on every chunk do X ?
let body = Body::wrap_stream(stream);
could I call bar.inc(1) on every interaction?
From the docs I see that there is a read_buffer but how to iterate over it in a way that I could use it for calling a custom function or also count the bytes send in the cased I could display "bytes sent" so far for example.

Answer 1

You can use TryStreamExt::inspect_ok, for instance, which will call a closure with a reference to every Ok(item) in the stream when that item is consumed.
use futures::stream::TryStreamExt;
use tokio_util::codec::{BytesCodec, FramedRead};
let stream = FramedRead::new(file, BytesCodec::new())
.inspect_ok(|chunk| {
// do X with chunk...
});
let body = Body::wrap_stream(stream);