[bugfix-157] no need of cancellable observable

src/shared/models/rx/cancellable-observable.class.ts

@@ -1,42 +0,0 @@
-import { BehaviorSubject, Observable, Observer, filter, lastValueFrom, take } from "rxjs";
-
-export class CancellableObservable<T> extends Observable<T> {
-    
-    private readonly _isCancelled$ = new BehaviorSubject(false);
-
-    constructor(subscriber: (obs: CancellableObserver<T>) => void) {
-
-        super((observer: Observer<T>) => {
-
-            const cancellableObserver: CancellableObserver<T> = Object.assign(observer, { 
-                $isCancelled: () => this.$isCancelled(),
-                onCancel: (callback: () => void) => this.onCancel(callback)
-            });
-
-            subscriber(cancellableObserver);
-        });
-
-        lastValueFrom(this).finally(() => this._isCancelled$.complete());
-    }
-
-    public cancel(): void {
-        this._isCancelled$.next(true);
-    }
-
-    public onCancel(callback: () => void): void {
-        this.$isCancelled().pipe(filter(isCancelled => isCancelled), take(1)).subscribe(callback);
-    }
-
-    public $isCancelled(): Observable<boolean> {
-        return this._isCancelled$.asObservable();
-    }
-
-    public isCancelled(): boolean {
-        return this._isCancelled$.getValue();
-    }
-}
-
-export interface CancellableObserver<T> extends Observer<T> {
-    readonly $isCancelled: () => Observable<boolean>;
-    readonly onCancel: (callback: () => void) => void;
-}