@Override
    protected void channelRead0(ChannelHandlerContext ctx, Http2Settings msg) throws Exception {
        promise.setSuccess();

        // Only care about the first settings message
        ctx.pipeline().remove(this);
    }
Wait for this handler to be added after the upgrade to HTTP/2, and for initial preface
handshake to complete.

@param timeout Time to wait
@param unit {@link TimeUnit} for {@code timeout}
@throws Exception if timeout or other failure occurs
remoting/remoting-http/src/main/java/com/alipay/sofa/rpc/transport/http/Http2SettingsHandler.java