Struct LengthCodec 

pub struct LengthCodec;

A simple Codec implementation sending your data by prefixing it by its length.

Example

This codec will most likely be used wrapped in another codec like so.

use asynchronous_codec::{Decoder, Encoder, LengthCodec};
use bytes::{Bytes, BytesMut};
use std::io::{Error, ErrorKind};

pub struct MyStringCodec(LengthCodec);

impl Encoder for MyStringCodec {
    type Item<'a> = String;
    type Error = Error;

    fn encode(&mut self, src: Self::Item<'_>, dst: &mut BytesMut) -> Result<(), Self::Error> {
        let bytes = Bytes::from(src);
        self.0.encode(bytes, dst)
    }
}

impl Decoder for MyStringCodec {
    type Item = String;
    type Error = Error;

    fn decode(&mut self, src: &mut BytesMut) -> Result<Option<Self::Item>, Self::Error> {
        match self.0.decode(src)? {
            Some(bytes) => {
                match String::from_utf8(bytes.to_vec()) {
                    Ok(string) => Ok(Some(string)),
                    Err(e) => Err(Error::new(ErrorKind::InvalidData, e))
                }
            },
            None => Ok(None),
        }
    }
}

Trait Implementations

impl Decoder for LengthCodec

type Item = Bytes

The type of items returned by decode

type Error = Error

The type of decoding errors.

fn decode( &mut self, src: &mut BytesMut, ) -> Result<Option<Self::Item>, Self::Error>

Decode an item from the src BytesMut into an item

fn decode_eof( &mut self, src: &mut BytesMut, ) -> Result<Option<Self::Item>, Self::Error>

Called when the input stream reaches EOF, signaling a last attempt to decode

impl Encoder for LengthCodec

type Item<'a> = Bytes

The type of items consumed by encode

type Error = Error

The type of encoding errors.

fn encode( &mut self, src: Self::Item<'_>, dst: &mut BytesMut, ) -> Result<(), Self::Error>

Encodes an item into the BytesMut provided by dst.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 0 bytes