Pipe RxJS observable to existing subject

javascript rxjs rxjs5
Estus Flask picture Estus Flask · Feb 20, 2018 · Viewed 7.7k times · Source

There is existing subject that is in use:

const fooSubject = new BehaviorSubject(null);

And there is another observable (another subject in this example):

const barSubject = new Subject();
barSubject.subscribe(
  value => fooSubject.next(),
  err => fooSubject.error(err),
  () => fooSubject.complete()
);

barSubject.next('bar');

The code works but looks clumsy.

Is there a better way to pipe (in broad sense, not necessarily using pipe operator) barSubject observable to fooSubject? It looks like an operation that could be handled by the library itself.

Answer

martin picture martin · Feb 20, 2018

Since Subject is already an observer with methods next(), error() and complete() you can just subscribe it to any Observable:

const fooSubject = new BehaviorSubject(null);

const barSubject = new Subject();
barSubject.subscribe(fooSubject);

barSubject.next('bar');

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