Convert an Observable stream to Completable

If I’m not mistaken, Completable is supposed to be a replacement for things like Observable<Void>, but it seems like combining them with Observables is messier.

It’s possible I’m doing something weird here, but this is what I want to do:

Given

Observable<Data> makeHttpCall();
Completable storeInDatabase(Data data);

Ideally I would be able to do something like this:

Completable syncData() {
    return makeHttpCall().flatMap(storeInDatabase);
}

But currently this is what I have:

Completable syncData() {
    return makeHttpCall()
        .flatMap(data -> storeInDatabase(data).toObservable<Void>())
        .toCompletable();
}

[akarnokd]

You can do this with some conversions:

Completable.merge(makeHttpCall().map(v -> storeInDatabase(v).toCompletable())).await();

[jmmk]

It looks like Completable.merge solves my issue of transforming Observable<Completable> to Completable then. Thanks!