rxjs/operators#expand TypeScript Examples

constructor(manifestService: DevToolsManifestService, private _router: Router) {
    this.intentionsByApp$ = this._appChange$
      .pipe(
        switchMap(() => manifestService.observeDependentIntentions$(this.appSymbolicName)),
        expand(intentions => this.filterFormControl.valueChanges.pipe(take(1), map(() => intentions))),
        map(intentions => filterManifestObjects(intentions, this.filterFormControl.value)),
        map(intentions => intentions.reduce((acc, intention) => Maps.addListValue(acc, intention.metadata.appSymbolicName, intention), new Map())),
      );
  }

constructor(manifestService: DevToolsManifestService, private _router: Router) {
    this.capabilitiesByApp$ = this._appChange$
      .pipe(
        switchMap(() => manifestService.observeDependingCapabilities$(this.appSymbolicName)),
        expand(capabilities => this.filterFormControl.valueChanges.pipe(take(1), map(() => capabilities))),
        map(capabilities => filterManifestObjects(capabilities, this.filterFormControl.value)),
        map(capabilities => capabilities.reduce((acc, capability) => Maps.addListValue(acc, capability.metadata.appSymbolicName, capability), new Map())),
      );
  }

private installCapabilitiesLookupRequestHandler(): void {
    Beans.get(MessageClient).observe$<ManifestObjectFilter>(ManifestRegistryTopics.LookupCapabilities)
      .pipe(takeUntil(this._destroy$))
      .subscribe((request: TopicMessage<ManifestObjectFilter>) => runSafe(() => {
        const replyTo = request.headers.get(MessageHeaders.ReplyTo);
        const appSymbolicName = request.headers.get(MessageHeaders.AppSymbolicName);
        const lookupFilter = request.body || {};

        // The queried capabilities may change on both, capability or intention change, because the computation
        // of visible and qualified capabilities depends on registered capabilities and manifested intentions.
        const registryChange$ = merge(this._capabilityStore.change$, this._intentionStore.change$);
        const finder$ = defer(() => of(this._capabilityStore.find(lookupFilter)));
        return finder$
          .pipe(
            expand(() => registryChange$.pipe(take(1), mergeMap(() => finder$))),
            filterArray(capability => this.isApplicationQualifiedForCapability(appSymbolicName, capability)),
            distinctUntilChanged((a, b) => JSON.stringify(a) === JSON.stringify(b)),
            takeUntilUnsubscribe(replyTo),
          )
          .subscribe(capabilities => { // eslint-disable-line rxjs/no-nested-subscribe
            Beans.get(MessageClient).publish<Capability[]>(replyTo, capabilities, {headers: new Map().set(MessageHeaders.Status, ResponseStatusCodes.OK)});
          });
      }));
  }

private installIntentionsLookupRequestHandler(): void {
    Beans.get(MessageClient).observe$<ManifestObjectFilter>(ManifestRegistryTopics.LookupIntentions)
      .pipe(takeUntil(this._destroy$))
      .subscribe((request: TopicMessage<ManifestObjectFilter>) => runSafe(() => {
        const replyTo = request.headers.get(MessageHeaders.ReplyTo);
        const lookupFilter = request.body || {};

        const finder$ = defer(() => of(this._intentionStore.find(lookupFilter)));
        return finder$
          .pipe(
            expand(() => this._intentionStore.change$.pipe(take(1), mergeMap(() => finder$))),
            distinctUntilChanged((a, b) => JSON.stringify(a) === JSON.stringify(b)),
            takeUntilUnsubscribe(replyTo),
          )
          .subscribe(intentions => { // eslint-disable-line rxjs/no-nested-subscribe
            Beans.get(MessageClient).publish<Intention[]>(replyTo, intentions, {headers: new Map().set(MessageHeaders.Status, ResponseStatusCodes.OK)});
          });
      }));
  }

private observeCapabilities$(): Observable<Capability[]> {
    return this.application$
      .pipe(
        switchMap(application => this._manifestService.capabilities$({appSymbolicName: application.symbolicName})),
        expand(capabilities => this.capabilityFilterFormControl.valueChanges.pipe(take(1), map(() => capabilities))),
        map(capabilities => filterManifestObjects(capabilities, this.capabilityFilterFormControl.value)),
      );
  }

private observeIntentions$(): Observable<Intention[]> {
    return this.application$
      .pipe(
        switchMap(application => this._manifestService.intentions$({appSymbolicName: application.symbolicName})),
        expand(intentions => this.intentionFilterFormControl.valueChanges.pipe(take(1), map(() => intentions))),
        map(intentions => filterManifestObjects(intentions, this.intentionFilterFormControl.value)),
      );
  }

constructor(shellService: ShellService, capabilityFilterSession: CapabilityFilterSession) {
    shellService.detailsTitle = 'Capabilities';
    this.capabilities$ = capabilityFilterSession.capabilities$()
      .pipe(
        expand(capabilities => this.filterFormControl.valueChanges.pipe(take(1), map(() => capabilities))),
        map(capabilities => filterManifestObjects(capabilities, this.filterFormControl.value)),
      );
  }

public capabilities$(): Observable<Capability[]> {
    return this._manifestService.capabilities$()
      .pipe(
        expand(capabilities => this._filterChange$.pipe(take(1), map(() => capabilities))),
        map(capabilities => this.filter(capabilities)),
      );
  }