113904: Fix null user handling

Author: Kuno Vercammen

src/app/process-page/overview/process-overview.component.ts

@@ -1,20 +1,21 @@
 import { Component, OnDestroy, OnInit } from '@angular/core';
-import { Observable, Subscription } from 'rxjs';
+import { Observable, Subscription, from as observableFrom } from 'rxjs';
 import { RemoteData } from '../../core/data/remote-data';
 import { PaginatedList } from '../../core/data/paginated-list.model';
 import { Process } from '../processes/process.model';
 import { PaginationComponentOptions } from '../../shared/pagination/pagination-component-options.model';
 import { EPersonDataService } from '../../core/eperson/eperson-data.service';
-import { getFirstSucceededRemoteDataPayload } from '../../core/shared/operators';
+import { getFirstCompletedRemoteData } from '../../core/shared/operators';
 import { EPerson } from '../../core/eperson/models/eperson.model';
-import { map, switchMap } from 'rxjs/operators';
+import { switchMap } from 'rxjs/operators';
 import { ProcessDataService } from '../../core/data/processes/process-data.service';
 import { PaginationService } from '../../core/pagination/pagination.service';
 import { FindListOptions } from '../../core/data/find-list-options.model';
 import { ProcessBulkDeleteService } from './process-bulk-delete.service';
 import { NgbModal } from '@ng-bootstrap/ng-bootstrap';
-import { hasValue } from '../../shared/empty.util';
+import { hasValue, isNotEmpty } from '../../shared/empty.util';
 import { DSONameService } from '../../core/breadcrumbs/dso-name.service';
+import { TranslateService } from '@ngx-translate/core';
 
 @Component({
   selector: 'ds-process-overview',
@@ -61,6 +62,7 @@ export class ProcessOverviewComponent implements OnInit, OnDestroy {
               protected modalService: NgbModal,
               public processBulkDeleteService: ProcessBulkDeleteService,
               protected dsoNameService: DSONameService,
+              private translateService: TranslateService,
   ) {
   }
 
@@ -83,10 +85,20 @@ export class ProcessOverviewComponent implements OnInit, OnDestroy {
    * @param id  ID of the EPerson
    */
   getEpersonName(id: string): Observable<string> {
-    return this.ePersonService.findById(id).pipe(
-      getFirstSucceededRemoteDataPayload(),
-      map((eperson: EPerson) => this.dsoNameService.getName(eperson)),
-    );
+    if (isNotEmpty(id)) {
+      return this.ePersonService.findById(id).pipe(
+        getFirstCompletedRemoteData(),
+        switchMap((rd: RemoteData<EPerson>) => {
+          if (rd.hasSucceeded) {
+            return observableFrom([this.dsoNameService.getName(rd.payload)]);
+          } else {
+            return this.translateService.get('process.overview.unknown.user');
+          }
+        })
+      );
+    } else {
+      return this.translateService.get('process.overview.unknown.user');
+    }
   }
 
   ngOnDestroy(): void {

src/assets/i18n/en.json5

@@ -5216,4 +5216,6 @@
 
   "access-control-option-end-date-note": "Select the date until which the related access condition is applied",
 
+  "process.overview.unknown.user": "Unknown",
+
 }