Rxjs

RxJS Learning Roadmap

1) Fundamentals

• What/Why Streams
• Observable, Observer, Subscription
• Observable vs Promise
• Creation:of, from, fromEvent

2) Core Operators

map filter take debounceTime throttleTime

• Transformation vs Filtering
• Combination: merge, concat, combineLatest, forkJoin
• Error handling: catchError, retry

3) Subjects

• Subject vs Observable
• Types: BehaviorSubject, ReplaySubject, AsyncSubject
• Multicasting & state sharing
• Cross‑component communication

4) Higher‑Order + Concurrency

• switchMap (keep latest)
• mergeMap (parallel)
• concatMap (queue)
• exhaustMap (ignore while running)
• When to use which

5) Angular + RxJS

• HttpClient streams & pipe()
• Reactive Forms: valueChanges
• Routing: ActivatedRoute observables
• AsyncPipe & memory safety (takeUntil)

6) Advanced Patterns

• Cold vs Hot, share / shareReplay
• Custom operators (operator factories)
• State with RxJS (towards NgRx)
• Testing observables (marbles)
• Anti‑patterns & best practices

7) Real‑World Projects

• Typeahead with debounceTime + switchMap
• Polling & live updates with interval
• Retry strategy with retryWhen
• Combining multiple calls with forkJoin / combineLatest