reactor-core/src/main/java/reactor/core/publisher/Flux.java
public final Flux<T> onErrorResume(Function<? super Throwable, ? extends Publisher<? extends T>> fallback) {
		return onAssembly(new FluxOnErrorResume<>(this, fallback));
	}
public final Flux<T> onErrorResume(Function<? super Throwable, ? extends Publisher<? extends T>> fallback) {
		return onAssembly(new FluxOnErrorResume<>(this, fallback));
	}
Subscribe to a returned fallback publisher when any error occurs, using a function to
choose the fallback depending on the error.

<p>
<img class="marble" src="doc-files/marbles/onErrorResumeForFlux.svg" alt="">

@param fallback the function to choose the fallback to an alternative {@link Publisher}

@return a {@link Flux} falling back upon source onError