Struct RMonitorDecoder

pub struct RMonitorDecoder { /* private fields */ }

A decoder for RMonitor records, which wraps an underlying LinesCodec to provide framing logic.

Implementations

impl RMonitorDecoder

pub fn new() -> Self

Returns an RMonitorDecoder for decoding RMonitor records from a TCP stream.

Note

The returned RMonitorDecoder will have an underlying LinesCodec with no upper bound on the length of a buffered line. Consider using new_with_max_length instead.

pub fn new_with_max_length(max_length: usize) -> Self

Returns an RMonitorDecoder where the underlying LinesCodec has a maximum line length limit.

It is recommended to set such a limit where the input to be supplied to the decoder is untrusted, as an attacker could send an unbounded amount of input with no newline characters.

Examples found in repository

examples/simple.rs (line 13)

async fn main() -> Result<(), Box<dyn Error>> {
    let stream = TcpStream::connect("127.0.0.1:50000").await?;

    let mut reader = FramedRead::new(stream, RMonitorDecoder::new_with_max_length(2048));

    while let Ok(Some(Ok(event))) = timeout(Duration::from_secs(5), reader.next()).await {
        println!("{:?}", event);
    }

    Ok(())
}

examples/sync.rs (line 17)

fn main() {
    let mut stream = TcpStream::connect("127.0.0.1:4000").expect("Failed to open connection");

    // .read() won't use the BytesMut directly in the appropriate manner,
    // so we do one extra bit of buffering here
    let mut read_buf = [0u8; 256];

    // Create the decode buffer, and a decoder with a maximum line length
    // of 2048.
    let mut buffer = BytesMut::with_capacity(4096);
    let mut decoder = RMonitorDecoder::new_with_max_length(2048);

    loop {
        let r = stream
            .read(&mut read_buf)
            .expect("Failed to read from stream");

        // Put only the read bytes into the decode buffer (not any trailing 0s)
        if r > 0 {
            buffer.put(&read_buf[..r]);
        }

        let maybe_record = decoder.decode(&mut buffer);

        match maybe_record {
            Ok(None) => {
                continue;
            }
            Ok(Some(r)) => println!("{:?}", r),
            Err(e) => println!("{:?}", e),
        }
    }
}

Trait Implementations

impl Debug for RMonitorDecoder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Decoder for RMonitorDecoder

type Item = Record

The type of decoded frames.

type Error = RMonitorCodecError

The type of unrecoverable frame decoding errors.

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

Attempts to decode a frame from the provided buffer of bytes.

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

A default method available to be called when there are no more bytes available to be read from the underlying I/O.

fn framed<T>(self, io: T) -> Framed<T, Self>

where T: AsyncRead + AsyncWrite, Self: Sized,

Provides a Stream and Sink interface for reading and writing to this Io object, using Decode and Encode to read and write the raw data.

impl Default for RMonitorDecoder

fn default() -> RMonitorDecoder

Returns the “default value” for a type.