Method Attach

agent/reconnectingpty/buffered.go:174–210

(ctx context.Context, connID string, conn net.Conn, height, width uint16, logger slog.Logger)

}

func (rpty *bufferedReconnectingPTY) Attach(ctx context.Context, connID string, conn net.Conn, height, width uint16, logger slog.Logger) error {
	logger.Info(ctx, "attach to reconnecting pty")

	// This will kill the heartbeat once we hit EOF or an error.
	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	err := rpty.doAttach(connID, conn)
	if err != nil {
		return err
	}

	defer func() {
		rpty.state.cond.L.Lock()
		defer rpty.state.cond.L.Unlock()
		delete(rpty.activeConns, connID)
	}()

	state, err := rpty.state.waitForStateOrContext(ctx, StateReady)
	if state != StateReady {
		return err
	}

	go heartbeat(ctx, rpty.timer, rpty.timeout)

	// Resize the PTY to initial height + width.
	err = rpty.ptty.Resize(height, width)
	if err != nil {
		// We can continue after this, it's not fatal!
		logger.Warn(ctx, "reconnecting PTY initial resize failed, but will continue", slog.Error(err))
		rpty.metrics.WithLabelValues("resize").Add(1)
	}

	// Pipe conn -> pty and block.  pty -> conn is handled in newBuffered().
	readConnLoop(ctx, conn, rpty.ptty, rpty.metrics, logger)
	return nil
}

// doAttach adds the connection to the map and replays the buffer.  It exists
// separately only for convenience to defer the mutex unlock which is not