DataSource: Return an Observable to deliver Panel data (6.4+)

In the Blog Post regarding the changes of 6.4 i’ve read that Datasources can also return an Observable. Im trying to do this, but unfortunately i cant figure out what kind of Data needs to be pushed by the Observable.
The query function of my Datasource looks somewhat like this:
query(options) {
var testData = [{ //Static testdata in the standard time-series format
const testObservable = new Observable(subscriber => {
return testObservable;

I built the whole thing into the JSON-Datasource.
I can see that grafana is subscribing to the Observable because of the console.log, but i cant get the panel to display anything. It says “expected Data to be Array, got undefined”.

I also had some Experiments using modules from ‘@grafana/data’ and ‘@grafana/ui’ (DataFrame etc.) but i couldnt get those to work (always some error somewhere :D).

So my Question is: what needs to be in the Observable for Grafana to process the Data? Or in what file can i see what happens to the Data from the Observable (then i could possibly find it out myself )

Best regards,