transport

Documentation

Overview

Package transport defines the Transport interface and ships three concrete implementations: an in-memory pair (for tests and same- process embedders), a WebSocket transport, and an NDJSON-over-stdio transport.

Index

• Variables
• func NewMemoryPair() (Transport, Transport)
• type Transport
  • func DialWebSocket(ctx context.Context, url string, opts WebSocketOptions) (Transport, error)
  • func NewStdioTransport(in io.Reader, out io.Writer) Transport
  • func NewWebSocket(conn *websocket.Conn) Transport
• type WebSocketOptions

Variables

var ErrClosed = errors.New("transport: closed")

ErrClosed is returned by Send and Recv after the transport is closed.

Functions

func NewMemoryPair

func NewMemoryPair() (Transport, Transport)

NewMemoryPair returns two transports connected via in-memory channels. Send on one returns Recv on the other. Useful for same-process tests and embedders.

Types

type Transport

type Transport interface {
	// Send delivers env to the peer, applying transport-specific
	// framing.
	Send(ctx context.Context, env arcp.Envelope) error
	// Recv blocks until the next envelope arrives, ctx is done, or the
	// transport closes.
	Recv(ctx context.Context) (arcp.Envelope, error)
	// Close terminates the transport. Subsequent Send calls return
	// ErrClosed; pending Recv calls unblock with io.EOF or an
	// equivalent wrapped error. Safe to call more than once.
	Close() error
}

Transport is the bidirectional envelope channel for one ARCP connection. Each side of a session holds exactly one Transport.

Implementations MUST honour ctx for both Send and Recv: both calls MUST return promptly when ctx.Done() is closed. Send and Recv MAY be called concurrently from different goroutines, but each end is expected to be driven by a single reader and a single writer.

func DialWebSocket

func DialWebSocket(ctx context.Context, url string, opts WebSocketOptions) (Transport, error)

DialWebSocket opens a client WebSocket transport to url.

func NewStdioTransport

func NewStdioTransport(in io.Reader, out io.Writer) Transport

NewStdioTransport wraps an io.Reader / io.Writer pair as a Transport using NDJSON framing (one JSON envelope per line). Closes the reader and writer (if they are io.Closer) when Close is called.

func NewWebSocket

func NewWebSocket(conn *websocket.Conn) Transport

NewWebSocket wraps an established websocket.Conn as a Transport. The transport takes ownership of conn; Close releases it.

type WebSocketOptions

type WebSocketOptions struct {
	// Subprotocols is the list of WebSocket subprotocols to negotiate.
	// Empty means "no subprotocol".
	Subprotocols []string
	// HTTPHeader is sent on the dial request (clients only).
	HTTPHeader http.Header
	// HTTPClient overrides the dial client. Optional.
	HTTPClient *http.Client
	// ReadLimit caps the inbound frame size in bytes. Zero uses 1 MiB.
	ReadLimit int64
}

WebSocketOptions configures a WebSocket transport.