Jave webflux process a String-response with id's

Question

I've a reactive API which receives the following String (image below). I want to process these ID's and perform a search query to my MongoDB and return a Flux with my model (filled with the ID's which existed in the database)

The code I got till now is:

public Mono<ServerResponse> findAllSpeakersBySessionId(ServerRequest request) {
    Flux<String> listWithIds = request.bodyToFlux(String.class);
    return ServerResponse.ok()
            .contentType(MediaType.APPLICATION_JSON)
            .body(speakerService.findAllByIds(listWithIds), String.class);
}


public Flux<Speaker> findAllByIds(Flux<String> speaker_Ids) {
    return this._speakerRepository.findAllById(speaker_Ids);
}

I'm new to this reactive programming and trying to get an understanding of it. How would I process this String-response so it looks up those ID's and returns me a Flux

Speaker-class

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
public class Speaker {
    @Id
    private String speaker_id;
    @NotNull
    private String name;
    private String skills;
    private String company;
    private String biography;
    private String specialisation;
    private List<String> session_Ids;
}