@Override
        public void onNext(DeframedMessage message) {
            if (message.isTrailer()) {
                final ByteBuf buf;
                try {
                    buf = InternalGrpcWebUtil.messageBuf(message, ctx.alloc());
                } catch (IOException e) {
                    // Ignore silently
                    return;
                }
                try {
                    final HttpHeaders trailers = InternalGrpcWebUtil.parseGrpcWebTrailers(buf);
                    if (trailers == null) {
                        return;
                    }
                    GrpcWebTrailers.set(ctx, trailers);
                } finally {
                    buf.release();
                }
            } else {
                message.close();
            }
        }
Utilities for working with <a href="https://grpc.io/docs/languages/web/basics/">gRPC-Web</a>.

<p>Note that this class will be removed once a retry {@link ClientInterceptor} is added.
See: https://github.com/line/armeria/issues/2860
grpc/src/main/java/com/linecorp/armeria/internal/client/grpc/GrpcWebTrailersExtractor.java