Struct StdioTransport 

pub struct StdioTransport<R, W> { /* private fields */ }

Stdio transport implementation.

Reads from stdin and writes to stdout using NDJSON framing. Integrates with asupersync for cancel-correct operation.

Wire Format

Messages are newline-delimited JSON:

• Each message is serialized as a single line of JSON
• Lines are terminated by \n (LF, not CRLF)
• Empty lines are ignored
• UTF-8 encoding is required

Implementations

impl<R, W> StdioTransport<R, W>

where R: Read, W: Write,

pub fn new(reader: R, writer: W) -> StdioTransport<R, W>

Creates a new stdio transport with custom reader/writer.

This is useful for testing with mock I/O.

impl StdioTransport<Stdin, Stdout>

pub fn stdio() -> StdioTransport<Stdin, Stdout>

Creates a transport using standard stdin/stdout.

This is the primary constructor for MCP servers running as subprocess.

impl<R, W> StdioTransport<R, W>

where R: Read, W: Write,

Helper to create request/response without cloning for internal use.

pub fn send_request_direct( &mut self, cx: &Cx, request: &JsonRpcRequest, ) -> Result<(), TransportError>

Send a request directly (avoids clone in trait method).

pub fn send_response_direct( &mut self, cx: &Cx, response: &JsonRpcResponse, ) -> Result<(), TransportError>

Send a response directly (avoids clone in trait method).

Trait Implementations

impl<R, W> Transport for StdioTransport<R, W>

where R: Read, W: Write,

fn send( &mut self, cx: &Cx, message: &JsonRpcMessage, ) -> Result<(), TransportError>

Send a JSON-RPC message through this transport.

fn recv(&mut self, cx: &Cx) -> Result<JsonRpcMessage, TransportError>

Receive the next JSON-RPC message from this transport.

fn close(&mut self) -> Result<(), TransportError>

Close the transport gracefully.

fn send_request( &mut self, cx: &Cx, request: &JsonRpcRequest, ) -> Result<(), TransportError>

Send a request through this transport.

fn send_response( &mut self, cx: &Cx, response: &JsonRpcResponse, ) -> Result<(), TransportError>

Send a response through this transport.

impl<R, W> TwoPhaseTransport for StdioTransport<R, W>

where R: Read, W: Write,

type Writer = W

The writer type for permits.

fn reserve_send( &mut self, cx: &Cx, ) -> Result<SendPermit<'_, <StdioTransport<R, W> as TwoPhaseTransport>::Writer>, TransportError>

Reserve a send slot.