Function tokio::io::stream_reader[][src]

pub fn stream_reader<S, B>(stream: S) -> StreamReader<S, B> where
    S: Stream<Item = Result<B, Error>>,
    B: Buf

Convert a stream of byte chunks into an AsyncRead.

Example

use bytes::Bytes;
use tokio::io::{stream_reader, AsyncReadExt};

// Create a stream from an iterator.
let stream = tokio::stream::iter(vec![
    Ok(Bytes::from_static(&[0, 1, 2, 3])),
    Ok(Bytes::from_static(&[4, 5, 6, 7])),
    Ok(Bytes::from_static(&[8, 9, 10, 11])),
]);

// Convert it to an AsyncRead.
let mut read = stream_reader(stream);

// Read five bytes from the stream.
let mut buf = [0; 5];
read.read_exact(&mut buf).await?;
assert_eq!(buf, [0, 1, 2, 3, 4]);

// Read the rest of the current chunk.
assert_eq!(read.read(&mut buf).await?, 3);
assert_eq!(&buf[..3], [5, 6, 7]);

// Read the next chunk.
assert_eq!(read.read(&mut buf).await?, 4);
assert_eq!(&buf[..4], [8, 9, 10, 11]);

// We have now reached the end.
assert_eq!(read.read(&mut buf).await?, 0);