Struct Framed

pub struct Framed<T, U> { /* private fields */ }

A unified Stream and Sink interface to an underlying I/O object, using the Encoder and Decoder traits to encode and decode frames.

Raw I/O objects work with byte sequences, but higher-level code usually wants to batch these into meaningful chunks, called “frames”. This method layers framing on top of an I/O object, by using the Encoder/Decoder traits to handle encoding and decoding of message frames. Note that the incoming and outgoing frame types may be distinct.

Implementations

impl<T, U> Framed<T, U>

where T: AsyncRead + AsyncWrite, U: Decoder,

pub fn new(io: T, codec: U) -> Framed<T, U>

This function returns a single object that is both Stream and Sink; grouping this into a single object is often useful for layering things like gzip or TLS, which require both read and write access to the underlying object.

impl<T, U> Framed<T, U>

pub fn codec_ref(&self) -> &U

Returns a reference to the underlying codec.

pub fn codec_mut(&mut self) -> &mut U

Returns a mutable reference to the underlying codec.

pub fn io_ref(&self) -> &T

Returns a reference to the underlying I/O stream wrapped by Frame.

Note that care should be taken to not tamper with the underlying stream of data coming in as it may corrupt the stream of frames otherwise being worked with.

pub fn io_mut(&mut self) -> &mut T

Returns a mutable reference to the underlying I/O stream.

Note that care should be taken to not tamper with the underlying stream of data coming in as it may corrupt the stream of frames otherwise being worked with.

pub fn io_pin(self: Pin<&mut Self>) -> Pin<&mut T>

Returns a Pin of a mutable reference to the underlying I/O stream.

pub fn is_read_buf_empty(&self) -> bool

Check if read buffer is empty.

pub fn is_write_buf_empty(&self) -> bool

Check if write buffer is empty.

pub fn is_write_buf_full(&self) -> bool

Check if write buffer is full.

pub fn is_write_ready(&self) -> bool

Check if framed is able to write more data.

Framed object considers ready if there is free space in write buffer.

pub fn replace_codec<U2>(self, codec: U2) -> Framed<T, U2>

Consume the Frame, returning Frame with different codec.

pub fn into_map_io<F, T2>(self, f: F) -> Framed<T2, U>

where F: Fn(T) -> T2,

Consume the Frame, returning Frame with different io.

pub fn into_map_codec<F, U2>(self, f: F) -> Framed<T, U2>

where F: Fn(U) -> U2,

Consume the Frame, returning Frame with different codec.

impl<T, U> Framed<T, U>

pub fn write<I>( self: Pin<&mut Self>, item: I, ) -> Result<(), <U as Encoder<I>>::Error>

where T: AsyncWrite, U: Encoder<I>,

Serialize item and write to the inner buffer

pub fn next_item( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Option<Result<<U as Decoder>::Item, U::Error>>>

where T: AsyncRead, U: Decoder,

Try to read underlying I/O stream and decode item.

pub fn flush<I>( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Result<(), U::Error>>

where T: AsyncWrite, U: Encoder<I>,

Flush write buffer to underlying I/O stream.

pub fn close<I>( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Result<(), U::Error>>

where T: AsyncWrite, U: Encoder<I>,

Flush write buffer and shutdown underlying I/O stream.

impl<T, U> Framed<T, U>

pub fn from_parts(parts: FramedParts<T, U>) -> Framed<T, U>

This function returns a single object that is both Stream and Sink; grouping this into a single object is often useful for layering things like gzip or TLS, which require both read and write access to the underlying object.

These objects take a stream, a read buffer and a write buffer. These fields can be obtained from an existing Framed with the into_parts method.

pub fn into_parts(self) -> FramedParts<T, U>

Consumes the Frame, returning its underlying I/O stream, the buffer with unprocessed data, and the codec.

Note that care should be taken to not tamper with the underlying stream of data coming in as it may corrupt the stream of frames otherwise being worked with.

Trait Implementations

impl<T, U> Debug for Framed<T, U>

where T: Debug, U: Debug,

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

Formats the value using the given formatter.

impl<T, U, I> Sink<I> for Framed<T, U>

where T: AsyncWrite, U: Encoder<I>, U::Error: From<Error>,

type Error = <U as Encoder<I>>::Error

The type of value produced by the sink when an error occurs.

fn poll_ready( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Attempts to prepare the Sink to receive a value.

fn start_send(self: Pin<&mut Self>, item: I) -> Result<(), Self::Error>

Begin the process of sending a value to the sink. Each call to this function must be preceded by a successful call to poll_ready which returned Poll::Ready(Ok(())).

fn poll_flush( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Flush any remaining output from this sink.

fn poll_close( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Result<(), Self::Error>>

Flush any remaining output and close this sink, if necessary.

impl<T, U> Stream for Framed<T, U>

where T: AsyncRead, U: Decoder,

type Item = Result<<U as Decoder>::Item, <U as Decoder>::Error>

Values yielded by the stream.

fn poll_next( self: Pin<&mut Self>, cx: &mut Context<'_>, ) -> Poll<Option<Self::Item>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.

impl<'__pin, T, U> Unpin for Framed<T, U>

where PinnedFieldsOf<__Origin<'__pin, T, U>>: Unpin,