Flux<T> and Mono<T> are Publisher types
Flux<T> is a publisher of 0 or more T where T is any given type
Mono<T> is a publisher of 0 or 1 of T where T is any given type
Flux.just - factory method of a discrete number of 0 or more elements to be emitted by
a Flux (publisher)
Flux.generate<T> - generate a signal stream of T, append a .take(n) to discretize
number of T generated to be consumed
Mono.just - factory method of a discrete number of 0 or 1 elements to be emitted by
a Mono (publisher)
text/event-stream - Server-Side Events - stream of API events, partners nicely
with publisher types