63945: Bitstream delete notifications, de-caching, reloading and small layout changes

src/app/+item-page/edit-item-page/item-bitstreams/item-bitstreams.component.ts

@@ -1,8 +1,8 @@
-import { Component, Inject, OnDestroy } from '@angular/core';
+import { ChangeDetectorRef, Component, Inject, OnDestroy } from '@angular/core';
 import { AbstractItemUpdateComponent } from '../abstract-item-update/abstract-item-update.component';
-import { map, switchMap, take } from 'rxjs/operators';
+import { filter, map, switchMap, take } from 'rxjs/operators';
 import { Bitstream } from '../../../core/shared/bitstream.model';
-import { getBundleNames, toBitstreamsArray, toBundleMap } from '../../../core/shared/item-bitstreams-utils';
+import { toBitstreamsArray, toBundleMap } from '../../../core/shared/item-bitstreams-utils';
 import { Observable } from 'rxjs/internal/Observable';
 import { FieldUpdate, FieldUpdates } from '../../../core/data/object-updates/object-updates.reducer';
 import { Subscription } from 'rxjs/internal/Subscription';
@@ -16,7 +16,14 @@ import { BitstreamDataService } from '../../../core/data/bitstream-data.service'
 import { FieldChangeType } from '../../../core/data/object-updates/object-updates.actions';
 import { isNotEmptyOperator } from '../../../shared/empty.util';
 import { zip as observableZip } from 'rxjs';
-import { RestResponse } from '../../../core/cache/response.models';
+import { ErrorResponse, RestResponse } from '../../../core/cache/response.models';
+import { ObjectCacheService } from '../../../core/cache/object-cache.service';
+import { RequestService } from '../../../core/data/request.service';
+import { getSucceededRemoteData } from '../../../core/shared/operators';
+import { Item } from '../../../core/shared/item.model';
+import { RemoteData } from '../../../core/data/remote-data';
+
+export const ORIGINAL_BUNDLE = 'ORIGINAL';
 
 @Component({
   selector: 'ds-item-bitstreams',
@@ -28,12 +35,24 @@ import { RestResponse } from '../../../core/cache/response.models';
  */
 export class ItemBitstreamsComponent extends AbstractItemUpdateComponent implements OnDestroy {
 
-  bundleNames$: Observable<string[]>;
-
+  /**
+   * A Map of the current item's bundles and respective FieldUpdates
+   * key:   Bundle Name
+   * value: FieldUpdates about the bundle's bitstreams
+   */
   updatesMap: Map<string, Observable<FieldUpdates>>;
 
+  /**
+   * A subscription keeping the updatesMap up-to-date
+   */
   updatesMapSub: Subscription;
 
+  /**
+   * A subscription that checks when the item is deleted in cache and reloads the item by sending a new request
+   * This is used to update the item in cache after bitstreams are deleted
+   */
+  itemUpdateSubscription: Subscription;
+
   constructor(
     public itemService: ItemDataService,
     public objectUpdatesService: ObjectUpdatesService,
@@ -42,7 +61,10 @@ export class ItemBitstreamsComponent extends AbstractItemUpdateComponent impleme
     public translateService: TranslateService,
     @Inject(GLOBAL_CONFIG) public EnvConfig: GlobalConfig,
     public route: ActivatedRoute,
-    public bitstreamService: BitstreamDataService
+    public bitstreamService: BitstreamDataService,
+    public objectCache: ObjectCacheService,
+    public requestService: RequestService,
+    public cdRef: ChangeDetectorRef
   ) {
     super(itemService, objectUpdatesService, router, notificationsService, translateService, EnvConfig, route);
   }
@@ -52,13 +74,19 @@ export class ItemBitstreamsComponent extends AbstractItemUpdateComponent impleme
    */
   ngOnInit(): void {
     super.ngOnInit();
-    this.bundleNames$ = this.item.bitstreams.pipe(getBundleNames());
+    this.initializeItemUpdate();
   }
 
+  /**
+   * Initialize the notification messages prefix
+   */
   initializeNotificationsPrefix(): void {
     this.notificationsPrefix = 'item.edit.bitstreams.notifications.';
   }
 
+  /**
+   * Initialize the original fields for the object-updates-service
+   */
   initializeOriginalFields(): void {
     this.item.bitstreams.pipe(
       toBitstreamsArray(),
@@ -68,6 +96,9 @@ export class ItemBitstreamsComponent extends AbstractItemUpdateComponent impleme
     });
   }
 
+  /**
+   * Initialize field updates
+   */
   initializeUpdates(): void {
     this.updates$ = this.item.bitstreams.pipe(
       toBitstreamsArray(),
@@ -80,10 +111,36 @@ export class ItemBitstreamsComponent extends AbstractItemUpdateComponent impleme
       bundleMap.forEach((bitstreams: Bitstream[], bundleName: string) => {
         updatesMap.set(bundleName, this.objectUpdatesService.getFieldUpdatesExclusive(this.url, bitstreams));
       });
+      if (updatesMap.size === 0) {
+        // Add an ORIGINAL bundle by default if the item doesn't contain any bitstreams
+        updatesMap.set(ORIGINAL_BUNDLE, undefined);
+      }
       this.updatesMap = updatesMap;
     });
   }
 
+  /**
+   * Update the item (and view) when it's removed in the request cache
+   * Also re-initialize the original fields and updates
+   */
+  initializeItemUpdate(): void {
+    this.itemUpdateSubscription = this.requestService.hasByHrefObservable(this.item.self).pipe(
+      filter((exists: boolean) => !exists),
+      switchMap(() => this.itemService.findById(this.item.uuid)),
+      getSucceededRemoteData(),
+    ).subscribe((itemRD: RemoteData<Item>) => {
+      this.item = itemRD.payload;
+      this.initializeOriginalFields();
+      this.initializeUpdates();
+      this.cdRef.detectChanges();
+    });
+  }
+
+  /**
+   * Submit the current changes
+   * Bitstreams marked as deleted send out a delete request to the rest API
+   * Display notifications and reset the current item/updates
+   */
   submit() {
     const removedBitstreams$ = this.item.bitstreams.pipe(
       toBitstreamsArray(),
@@ -94,11 +151,53 @@ export class ItemBitstreamsComponent extends AbstractItemUpdateComponent impleme
     );
     removedBitstreams$.pipe(
       take(1),
-      switchMap((removedBistreams: Bitstream[]) => observableZip(...removedBistreams.map((bitstream: Bitstream) => this.bitstreamService.delete(bitstream))))
-    ).subscribe();
+      switchMap((removedBistreams: Bitstream[]) => observableZip(...removedBistreams.map((bitstream: Bitstream) => this.bitstreamService.deleteAndReturnResponse(bitstream))))
+    ).subscribe((responses: RestResponse[]) => {
+      this.displayNotifications(responses);
+      this.reset();
+    });
   }
 
+  /**
+   * Display notifications
+   * - Error notification for each failed response with their message
+   * - Success notification in case there's at least one successful response
+   * @param responses
+   */
+  displayNotifications(responses: RestResponse[]) {
+    const failedResponses = responses.filter((response: RestResponse) => !response.isSuccessful);
+    const successfulResponses = responses.filter((response: RestResponse) => response.isSuccessful);
+
+    failedResponses.forEach((response: ErrorResponse) => {
+      this.notificationsService.error(this.getNotificationTitle('failed'), response.errorMessage);
+    });
+    if (successfulResponses.length > 0) {
+      this.notificationsService.success(this.getNotificationTitle('saved'), this.getNotificationContent('saved'));
+    }
+  }
+
+  /**
+   * De-cache the current item (it should automatically reload due to itemUpdateSubscription)
+   */
+  reset() {
+    this.updatesMap = undefined;
+    this.refreshItemCache();
+    this.initializeItemUpdate();
+  }
+
+  /**
+   * Remove the current item's cache from object- and request-cache
+   */
+  refreshItemCache() {
+    this.objectCache.remove(this.item.self);
+    this.requestService.removeByHrefSubstring(this.item.self);
+  }
+
+  /**
+   * Unsubscribe from open subscriptions whenever the component gets destroyed
+   */
   ngOnDestroy(): void {
     this.updatesMapSub.unsubscribe();
+    this.itemUpdateSubscription.unsubscribe();
   }
 }