passing dynamicmetadata from envoy to mixer

I found discussion and PRs about passing dynamicmetadata to mixer

I’m trying to set dynamicmetadata with lua and pass it to mixer to be able to put it in accesslog.

As far as I can see with tcpdump dynamicmetadata is not passed to mixer in my case.

I can’t find any examples or documantation and looking for help.

Are there any additional steps necessary to make to pass dynamicmetadata to mixer?

Lua sample code.

  { a = "b", c = "d" }