@Nullable
    static ServiceRequestContext currentOrNull() {
        final RequestContext ctx = RequestContext.currentOrNull();
        if (ctx == null) {
            return null;
        }

        return ctx.root();
    }
Returns the server-side context of the {@link Request} that is being handled in the current thread.
If the context is a {@link ClientRequestContext}, {@link ClientRequestContext#root()} is returned.

@return the {@link ServiceRequestContext} available in the current thread,
        or {@code null} if unavailable.
core/src/main/java/com/linecorp/armeria/server/ServiceRequestContext.java