Struct OvpnCodec 

pub struct OvpnCodec { /* private fields */ }

Tokio codec for the OpenVPN management interface.

The encoder serializes typed OvpnCommand values into correct wire-format bytes, including proper escaping and multi-line block framing. The decoder uses command-tracking state to correctly distinguish single-line from multi-line responses, and accumulates multi-line >CLIENT: notifications into a single OvpnMessage before emitting them.

Sequential usage

The OpenVPN management protocol is strictly sequential: each command produces exactly one response, and the server processes commands one at a time. This codec tracks which response type to expect from the last encoded command. You must fully drain [decode()] (until it returns Ok(None) or the expected response is received) before calling [encode()] again. Encoding a new command while a multi-line response or CLIENT notification is still being accumulated will overwrite the tracking state and corrupt decoding.

In debug builds, encode() asserts that no accumulation is in progress.

Implementations

impl OvpnCodec

pub fn new() -> Self

Create a new codec with default state, ready to encode commands and decode responses.

pub fn with_max_multi_line_lines(self, limit: AccumulationLimit) -> Self

Set the maximum number of lines accumulated in a multi-line response before the decoder returns an error.

pub fn with_max_client_env_entries(self, limit: AccumulationLimit) -> Self

Set the maximum number of ENV entries accumulated for >CLIENT: notifications before the decoder returns an error.

pub fn with_encoder_mode(self, mode: EncoderMode) -> Self

Set the encoder mode for handling unsafe characters in user-supplied strings.

The default is EncoderMode::Sanitize, which silently strips \n, \r, and \0. Use EncoderMode::Strict to reject inputs containing those characters with an error instead.

Trait Implementations

impl Decoder for OvpnCodec

type Item = OvpnMessage

The type of decoded frames.

type Error = Error

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 OvpnCodec

fn default() -> Self

Returns the “default value” for a type.

impl Encoder<OvpnCommand> for OvpnCodec

type Error = Error

The type of encoding errors.

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

Encodes a frame into the buffer provided.