for callback in route.callbacks:
                    if isinstance(callback, routing.APIRoute):
                        (
                            cb_path,
                            cb_security_schemes,
                            cb_definitions,
                        ) = get_openapi_path(
                            route=callback,
                            operation_ids=operation_ids,

// If the remote is restarted will return ErrRemoteRestart.
// If nil will be returned remote call sent EOF or ErrDone is returned by the callback.
// If ErrDone is returned on cb nil will be returned.
func (c *Connection) Stateless(ctx context.Context, h HandlerID, req []byte, cb func([]byte) error) error {
	client, err := c.newMuxClient(ctx)
	if err != nil {
		return err
	}
	defer c.outgoing.Delete(client.MuxID)

		reader = etag.NewReader(ctx, reader, nil, nil)
		wantEncryption := crypto.Requested(r.Header)
		s2c, cb := newS2CompressReader(reader, actualSize, wantEncryption)
		dstOpts.IndexCB = cb
		defer s2c.Close()
		reader = etag.Wrap(s2c, reader)
		length = -1
	} else {
		delete(srcInfo.UserDefined, ReservedMetadataPrefix+"compression")