Struct tokio_util::io::StreamReader

source · [−]
pub struct StreamReader<S, B> { /* private fields */ }
Expand description

Convert a Stream of byte chunks into an AsyncRead.

This type performs the inverse operation of ReaderStream.

Example

use bytes::Bytes;
use tokio::io::{AsyncReadExt, Result};
use tokio_util::io::StreamReader;

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

// Convert it to an AsyncRead.
let mut read = StreamReader::new(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);

Implementations

Convert a stream of byte chunks into an AsyncRead.

The item should be a Result with the ok variant being something that implements the Buf trait (e.g. Vec<u8> or Bytes). The error should be convertible into an io error.

Gets a reference to the underlying stream.

It is inadvisable to directly read from the underlying stream.

Gets a mutable reference to the underlying stream.

It is inadvisable to directly read from the underlying stream.

Gets a pinned mutable reference to the underlying stream.

It is inadvisable to directly read from the underlying stream.

Consumes this BufWriter, returning the underlying stream.

Note that any leftover data in the internal buffer is lost.

Trait Implementations

Attempts to return the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to poll_read. Read more

Attempts to read from the AsyncRead into buf. Read more

Formats the value using the given formatter. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Reads all bytes into buf until the delimiter byte or EOF is reached. Read more

Reads all bytes until a newline (the 0xA byte) is reached, and append them to the provided buffer. Read more

Returns a stream of the contents of this reader split on the byte byte. Read more

Returns the contents of the internal buffer, filling it with more data from the inner reader if it is empty. Read more

Tells this buffer that amt bytes have been consumed from the buffer, so they should no longer be returned in calls to read. Read more

Returns a stream over the lines of this reader. This method is the async equivalent to BufRead::lines. Read more

Creates a new AsyncRead instance that chains this stream with next. Read more

Pulls some bytes from this source into the specified buffer, returning how many bytes were read. Read more

Pulls some bytes from this source into the specified buffer, advancing the buffer’s internal cursor. Read more

Reads the exact number of bytes required to fill buf. Read more

Reads an unsigned 8 bit integer from the underlying reader. Read more

Reads a signed 8 bit integer from the underlying reader. Read more

Reads an unsigned 16-bit integer in big-endian order from the underlying reader. Read more

Reads a signed 16-bit integer in big-endian order from the underlying reader. Read more

Reads an unsigned 32-bit integer in big-endian order from the underlying reader. Read more

Reads a signed 32-bit integer in big-endian order from the underlying reader. Read more

Reads an unsigned 64-bit integer in big-endian order from the underlying reader. Read more

Reads an signed 64-bit integer in big-endian order from the underlying reader. Read more

Reads an unsigned 128-bit integer in big-endian order from the underlying reader. Read more

Reads an signed 128-bit integer in big-endian order from the underlying reader. Read more

Reads an 32-bit floating point type in big-endian order from the underlying reader. Read more

Reads an 64-bit floating point type in big-endian order from the underlying reader. Read more

Reads an unsigned 16-bit integer in little-endian order from the underlying reader. Read more

Reads a signed 16-bit integer in little-endian order from the underlying reader. Read more

Reads an unsigned 32-bit integer in little-endian order from the underlying reader. Read more

Reads a signed 32-bit integer in little-endian order from the underlying reader. Read more

Reads an unsigned 64-bit integer in little-endian order from the underlying reader. Read more

Reads an signed 64-bit integer in little-endian order from the underlying reader. Read more

Reads an unsigned 128-bit integer in little-endian order from the underlying reader. Read more

Reads an signed 128-bit integer in little-endian order from the underlying reader. Read more

Reads an 32-bit floating point type in little-endian order from the underlying reader. Read more

Reads an 64-bit floating point type in little-endian order from the underlying reader. Read more

Reads all bytes until EOF in this source, placing them into buf. Read more

Reads all bytes until EOF in this source, appending them to buf. Read more

Creates an adaptor which reads at most limit bytes from it. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.