Struct MqttCodec 

pub struct MqttCodec {
    pub protocol_level: ProtocolLevel,
    pub max_packet_size: Option<usize>,
}

Fields

protocol_level: ProtocolLevel

Tracks the protocol level negotiated during CONNECT. Defaults to V311 for the first packet.

max_packet_size: Option<usize>

Maximum allowed remaining length (bytes) for any MQTT packet. None = no limit (backward-compatible default). When exceeded, decode() returns MqttError::PayloadTooLarge before allocating memory for the packet body.

Implementations

impl MqttCodec

pub fn new() -> Self

pub fn with_max_packet_size(max_size: usize) -> Self

Create a codec with a maximum packet size limit.

Any packet whose remaining_length exceeds max_size is rejected at the decode level before memory is allocated.

Trait Implementations

impl Decoder for MqttCodec

type Item = MqttPacket

The type of decoded frames.

type Error = MqttError

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 MqttCodec

fn default() -> Self

Returns the “default value” for a type.

impl Encoder<MqttPacket> for MqttCodec

type Error = MqttError

The type of encoding errors.

fn encode( &mut self, item: MqttPacket, dst: &mut BytesMut, ) -> Result<(), Self::Error>

Encodes a frame into the buffer provided.