.

Author: jba

mcp/client.go

@@ -142,18 +142,18 @@ type ClientSession struct {
 	client           *Client
 	initializeResult *InitializeResult
 	keepaliveCancel  context.CancelFunc
-	sessionIDFunc    func() string
+	mcpConn          Connection
 }
 
-func (cs *ClientSession) setSessionIDFunc(f func() string) {
-	cs.sessionIDFunc = f
+func (cs *ClientSession) setConn(c Connection) {
+	cs.mcpConn = c
 }
 
 func (cs *ClientSession) ID() string {
-	if cs.sessionIDFunc == nil {
+	if cs.mcpConn == nil {
 		return ""
 	}
-	return cs.sessionIDFunc()
+	return cs.mcpConn.SessionID()
 }
 
 // Close performs a graceful close of the connection, preventing new requests

mcp/server.go

@@ -496,23 +496,23 @@ func (ss *ServerSession) NotifyProgress(ctx context.Context, params *ProgressNot
 type ServerSession struct {
 	server           *Server
 	conn             *jsonrpc2.Connection
-	sessionIDFunc    func() string
+	mcpConn          Connection
 	mu               sync.Mutex
 	logLevel         LoggingLevel
 	initializeParams *InitializeParams
 	initialized      bool
 	keepaliveCancel  context.CancelFunc
 }
 
-func (ss *ServerSession) setSessionIDFunc(f func() string) {
-	ss.sessionIDFunc = f
+func (ss *ServerSession) setConn(c Connection) {
+	ss.mcpConn = c
 }
 
 func (ss *ServerSession) ID() string {
-	if ss.sessionIDFunc == nil {
+	if ss.mcpConn == nil {
 		return ""
 	}
-	return ss.sessionIDFunc()
+	return ss.mcpConn.SessionID()
 }
 
 // Ping pings the client.

mcp/sse.go

@@ -264,7 +264,7 @@ type sseServerConn struct {
 }
 
 // TODO(jba): get the session ID. (Not urgent because SSE transports have been removed from the spec.)
-func (s sseServerConn) sessionID() string { return "" }
+func (s sseServerConn) SessionID() string { return "" }
 
 // Read implements jsonrpc2.Reader.
 func (s sseServerConn) Read(ctx context.Context) (JSONRPCMessage, error) {
@@ -522,7 +522,7 @@ type sseClientConn struct {
 }
 
 // TODO(jba): get the session ID. (Not urgent because SSE transports have been removed from the spec.)
-func (c *sseClientConn) sessionID() string { return "" }
+func (c *sseClientConn) SessionID() string { return "" }
 
 func (c *sseClientConn) isDone() bool {
 	c.mu.Lock()

mcp/streamable.go

@@ -161,7 +161,7 @@ func NewStreamableServerTransport(sessionID string) *StreamableServerTransport {
 	}
 }
 
-func (t *StreamableServerTransport) sessionID() string {
+func (t *StreamableServerTransport) SessionID() string {
 	return t.id
 }
 
@@ -642,7 +642,7 @@ type streamableClientConn struct {
 	err error
 }
 
-func (c *streamableClientConn) sessionID() string {
+func (c *streamableClientConn) SessionID() string {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 	return c._sessionID

mcp/transport.go

@@ -50,7 +50,7 @@ type Connection interface {
 	Read(context.Context) (JSONRPCMessage, error)
 	Write(context.Context, JSONRPCMessage) error
 	Close() error // may be called concurrently by both peers
-	sessionID() string
+	SessionID() string
 }
 
 // A StdioTransport is a [Transport] that communicates over stdin/stdout using
@@ -95,7 +95,7 @@ type binder[T handler] interface {
 
 type handler interface {
 	handle(ctx context.Context, req *JSONRPCRequest) (any, error)
-	setSessionIDFunc(func() string) // so Sessions can get the session ID
+	setConn(Connection)
 }
 
 func connect[H handler](ctx context.Context, t Transport, b binder[H]) (H, error) {
@@ -126,7 +126,7 @@ func connect[H handler](ctx context.Context, t Transport, b binder[H]) (H, error
 		},
 	})
 	assert(preempter.conn != nil, "unbound preempter")
-	h.setSessionIDFunc(conn.sessionID)
+	h.setConn(conn)
 	return h, nil
 }
 
@@ -203,7 +203,7 @@ type loggingConn struct {
 	w        io.Writer
 }
 
-func (c *loggingConn) sessionID() string { return c.delegate.sessionID() }
+func (c *loggingConn) SessionID() string { return c.delegate.SessionID() }
 
 // loggingReader is a stream middleware that logs incoming messages.
 func (s *loggingConn) Read(ctx context.Context) (JSONRPCMessage, error) {
@@ -290,7 +290,7 @@ func newIOConn(rwc io.ReadWriteCloser) *ioConn {
 	}
 }
 
-func (c *ioConn) sessionID() string { return "" }
+func (c *ioConn) SessionID() string { return "" }
 
 // addBatch records a msgBatch for an incoming batch payload.
 // It returns an error if batch is malformed, containing previously seen IDs.