Enum ServeStream 

pub enum ServeStream {
    Unix(UnixStream),
    Http(Box<dyn Write + Send>),
}

The served-MCP transport, type-erased to one concrete enum so the connection registry (SharedWriter, Subscriber) stays monomorphic across transports while the same connection code serves each. The socket variants are Read + Write with a try_clone (their write half is shared with the threads that push NDJSON notifications). The Http variant is a write-only SSE sink: an HTTP subscription stream’s write half, so an HTTP subscriber registers in the SAME SubRegistry and the embedder’s existing notify_* calls reach it transparently — the framing (NDJSON vs SSE data: events) is chosen per-variant in write_notification.

Variants

Unix(UnixStream)

A unix-domain-socket peer.

Http(Box<dyn Write + Send>)

The write half of an HTTP subscription (SSE) stream — a push-only sink. Never read from, never a reply channel; notifications are framed as SSE data: events. Boxed so it spans plain TCP and (feature tls) TLS.

Implementations

impl ServeStream

pub fn try_clone(&self) -> Result<ServeStream>

Clone the handle (a second fd onto the same connection) for the shared write half. Mirrors UnixStream::try_clone. The Http sink is single-owner (its SharedWriter is built directly from the stream half), so it is never cloned — attempting to is an error.

pub fn set_write_timeout(&self, dur: Option<Duration>) -> Result<()>

Bound a stalled-but-alive peer so it can’t pin the writer Mutex forever. The HTTP sink sets its timeout on the underlying stream before boxing.

pub fn write_notification(&mut self, note: &Notification) -> Result<()>

Push one notification, framed for this transport: NDJSON (one JSON object + \n) on the socket variants, an SSE data: event on Http. This is the single seam the notify_* push helpers write through.

pub fn write_response(&mut self, resp: &Response) -> Result<()>

Write one JSON-RPC RESPONSE frame with per-transport framing — the server-streaming twin of [write_notification]: an HTTP (SSE) sink gets a data: event, a socket peer gets an NDJSON line. Streaming method handlers (A2A StreamResponse frames) push through this so one handler serves every transport.

Trait Implementations

impl Read for ServeStream

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Pull some bytes from this source into the specified buffer, returning how many bytes were read.

fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> Result<usize, Error>

Like read, except that it reads into a slice of buffers.

fn is_read_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Reader has an efficient read_vectored implementation.

fn read_to_end(&mut self, buf: &mut Vec<u8>) -> Result<usize, Error>

Reads all bytes until EOF in this source, placing them into buf.

fn read_to_string(&mut self, buf: &mut String) -> Result<usize, Error>

Reads all bytes until EOF in this source, appending them to buf.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Error>

Reads the exact number of bytes required to fill buf.

fn read_buf(&mut self, buf: BorrowedCursor<'_, u8>) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Pull some bytes from this source into the specified buffer.

fn read_buf_exact( &mut self, cursor: BorrowedCursor<'_, u8>, ) -> Result<(), Error>

🔬This is a nightly-only experimental API. (read_buf)

Reads the exact number of bytes required to fill cursor.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Read.

fn bytes(self) -> Bytes<Self>

where Self: Sized,

Transforms this Read instance to an Iterator over its bytes.

fn chain<R>(self, next: R) -> Chain<Self, R>

where R: Read, Self: Sized,

Creates an adapter which will chain this stream with another.

fn take(self, limit: u64) -> Take<Self>

where Self: Sized,

Creates an adapter which will read at most limit bytes from it.

fn read_array<const N: usize>(&mut self) -> Result<[u8; N], Error>

where Self: Sized,

🔬This is a nightly-only experimental API. (read_array)

Read and return a fixed array of bytes from this source.

fn read_le<T>(&mut self) -> Result<T, Error>

where T: FromEndianBytes, Self: Sized,

🔬This is a nightly-only experimental API. (read_le)

Read and return a type (e.g. an integer) in little-endian order.

fn read_be<T>(&mut self) -> Result<T, Error>

where T: FromEndianBytes, Self: Sized,

🔬This is a nightly-only experimental API. (read_le)

Read and return a type (e.g. an integer) in big-endian order.

impl Write for ServeStream

fn write(&mut self, buf: &[u8]) -> Result<usize>

Writes a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flushes this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn is_write_vectored(&self) -> bool

🔬This is a nightly-only experimental API. (can_vector)

Determines if this Writer has an efficient write_vectored implementation.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice<'_>]) -> Result<(), Error>

🔬This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, args: Arguments<'_>) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Write.