97075: Edit-metadata redesign messages + JSDocs

src/app/dso-shared/dso-edit-metadata/dso-edit-metadata-form.ts

@@ -6,19 +6,50 @@ import { MetadataPatchRemoveOperation } from '../../core/data/object-updates/pat
 import { MetadataPatchAddOperation } from '../../core/data/object-updates/patch-operation-service/operations/metadata/metadata-patch-add-operation.model';
 import { MetadataPatchOperation } from '../../core/data/object-updates/patch-operation-service/operations/metadata/metadata-patch-operation.model';
 
+/* tslint:disable:max-classes-per-file */
+
+/**
+ * Enumeration for the type of change occurring on a metadata value
+ */
 export enum DsoEditMetadataChangeType {
   UPDATE = 1,
   ADD = 2,
   REMOVE = 3
 }
 
+/**
+ * Class holding information about a metadata value and its changes within an edit form
+ */
 export class DsoEditMetadataValue {
+  /**
+   * The original metadata value (should stay the same!) used to compare changes with
+   */
   originalValue: MetadataValue;
+
+  /**
+   * The new value, dynamically changing
+   */
   newValue: MetadataValue;
+
+  /**
+   * A value that can be used to undo any discarding that took place
+   */
   reinstatableValue: MetadataValue;
 
+  /**
+   * Whether or not this value is currently being edited or not
+   */
   editing = false;
+
+  /**
+   * The type of change that's taking place on this metadata value
+   * Empty if no changes are made
+   */
   change: DsoEditMetadataChangeType;
+
+  /**
+   * A type or change that can be used to undo any discarding that took place
+   */
   reinstatableChange: DsoEditMetadataChangeType;
 
   constructor(value: MetadataValue, added = false) {
@@ -30,6 +61,12 @@ export class DsoEditMetadataValue {
     }
   }
 
+  /**
+   * Save the current changes made to the metadata value
+   * This will set the type of change to UPDATE if the new metadata value's value and/or language are different from
+   * the original value
+   * It will also set the editing flag to false
+   */
   confirmChanges() {
     if (hasNoValue(this.change) || this.change === DsoEditMetadataChangeType.UPDATE) {
       if ((this.originalValue.value !== this.newValue.value || this.originalValue.language !== this.newValue.language)) {
@@ -41,10 +78,19 @@ export class DsoEditMetadataValue {
     this.editing = false;
   }
 
+  /**
+   * Returns if the current value contains changes or not
+   * If the metadata value contains changes, but they haven't been confirmed yet through confirmChanges(), this might
+   * return false (which is desired)
+   */
   hasChanges(): boolean {
     return hasValue(this.change);
   }
 
+  /**
+   * Discard the current changes and mark the value and change type re-instatable by storing them in their relevant
+   * properties
+   */
   discardAndMarkReinstatable(): void {
     if (this.change === DsoEditMetadataChangeType.UPDATE) {
       this.reinstatableValue = this.newValue;
@@ -53,12 +99,19 @@ export class DsoEditMetadataValue {
     this.discard();
   }
 
+  /**
+   * Discard the current changes
+   * Call discardAndMarkReinstatable() instead, if the discard should be re-instatable
+   */
   discard(): void {
     this.change = undefined;
     this.newValue = Object.assign(new MetadataValue(), this.originalValue);
     this.editing = false;
   }
 
+  /**
+   * Re-instate (undo) the last discard by replacing the value and change type with their reinstate properties (if present)
+   */
   reinstate(): void {
     if (hasValue(this.reinstatableValue)) {
       this.newValue = this.reinstatableValue;
@@ -70,20 +123,50 @@ export class DsoEditMetadataValue {
     }
   }
 
+  /**
+   * Returns if either the value or change type have a re-instatable property
+   * This will be the case if a discard has taken place that undid changes to the value or type
+   */
   isReinstatable(): boolean {
     return hasValue(this.reinstatableValue) || hasValue(this.reinstatableChange);
   }
 }
 
+/**
+ * Class holding information about the metadata of a DSpaceObject and its changes within an edit form
+ */
 export class DsoEditMetadataForm {
+  /**
+   * List of original metadata field keys (before any changes took place)
+   */
   originalFieldKeys: string[];
+
+  /**
+   * List of current metadata field keys (includes new fields for values added by the user)
+   */
   fieldKeys: string[];
+
+  /**
+   * Current state of the form
+   * Key: Metadata field
+   * Value: List of {@link DsoEditMetadataValue}s for the metadata field
+   */
   fields: {
     [mdField: string]: DsoEditMetadataValue[],
   };
+
+  /**
+   * A map of previously added metadata values before a discard of the form took place
+   * This can be used to re-instate the entire form to before the discard taking place
+   */
   reinstatableNewValues: {
     [mdField: string]: DsoEditMetadataValue[],
   };
+
+  /**
+   * A (temporary) new metadata value added by the user, not belonging to a metadata field yet
+   * This value will be finalised and added to a field using setMetadataField()
+   */
   newValue: DsoEditMetadataValue;
 
   constructor(metadata: MetadataMap) {
@@ -98,18 +181,32 @@ export class DsoEditMetadataForm {
     });
   }
 
+  /**
+   * Add a new temporary value for the user to edit
+   */
   add(): void {
     if (hasNoValue(this.newValue)) {
       this.newValue = new DsoEditMetadataValue(new MetadataValue(), true);
     }
   }
 
+  /**
+   * Add the temporary value to a metadata field
+   * Clear the temporary value afterwards
+   * @param mdField
+   */
   setMetadataField(mdField: string) {
     this.newValue.editing = false;
     this.addValueToField(this.newValue, mdField);
     this.newValue = undefined;
   }
 
+  /**
+   * Add a value to a metadata field within the map
+   * @param value
+   * @param mdField
+   * @private
+   */
   private addValueToField(value: DsoEditMetadataValue, mdField: string) {
     if (isEmpty(this.fields[mdField])) {
       this.fieldKeys.push(mdField);
@@ -118,6 +215,11 @@ export class DsoEditMetadataForm {
     this.fields[mdField].push(value);
   }
 
+  /**
+   * Remove a value from a metadata field on a given index (this actually removes the value, not just marking it deleted)
+   * @param mdField
+   * @param index
+   */
   remove(mdField: string, index: number) {
     if (isNotEmpty(this.fields[mdField])) {
       this.fields[mdField].splice(index, 1);
@@ -128,10 +230,17 @@ export class DsoEditMetadataForm {
     }
   }
 
+  /**
+   * Returns if at least one value within the form contains a change
+   */
   hasChanges(): boolean {
     return Object.values(this.fields).some((values) => values.some((value) => value.hasChanges()));
   }
 
+  /**
+   * Discard all changes within the form and store their current values within re-instatable properties so they can be
+   * undone afterwards
+   */
   discard(): void {
     Object.entries(this.fields).forEach(([field, values]) => {
       let removeFromIndex = -1;
@@ -174,6 +283,9 @@ export class DsoEditMetadataForm {
     this.reinstatableNewValues = {};
   }
 
+  /**
+   * Returns if at least one value contains a re-instatable property, meaning a discard can be reversed
+   */
   isReinstatable(): boolean {
     return isNotEmpty(this.reinstatableNewValues) ||
       Object.values(this.fields)
@@ -181,6 +293,9 @@ export class DsoEditMetadataForm {
           .some((value) => value.isReinstatable()));
   }
 
+  /**
+   * Get the json PATCH operations for the current changes within this form
+   */
   getOperations(): Operation[] {
     const operations: Operation[] = [];
     Object.entries(this.fields).forEach(([field, values]) => {
@@ -211,3 +326,4 @@ export class DsoEditMetadataForm {
     return operations;
   }
 }
+/* tslint:enable:max-classes-per-file */

src/app/dso-shared/dso-edit-metadata/dso-edit-metadata.component.html

@@ -20,12 +20,12 @@
   </div>
 
   <div class="d-flex flex-row ds-field-row ds-header-row">
-    <div class="lbl-cell">Field</div>
+    <div class="lbl-cell">{{ dsoType + '.edit.metadata.headers.field' | translate }}</div>
     <div class="flex-grow-1">
       <div class="d-flex flex-row">
-        <div class="flex-grow-1 ds-flex-cell ds-value-cell"><b class="dont-break-out preserve-line-breaks">Value</b></div>
+        <div class="flex-grow-1 ds-flex-cell ds-value-cell"><b class="dont-break-out preserve-line-breaks">{{ dsoType + '.edit.metadata.headers.value' | translate }}</b></div>
-        <div class="ds-flex-cell ds-lang-cell"><b>Lang</b></div>
+        <div class="ds-flex-cell ds-lang-cell"><b>{{ dsoType + '.edit.metadata.headers.language' | translate }}</b></div>
-        <div class="text-center ds-flex-cell ds-edit-cell"><b>Edit</b></div>
+        <div class="text-center ds-flex-cell ds-edit-cell"><b>{{ dsoType + '.edit.metadata.headers.edit' | translate }}</b></div>
       </div>
     </div>
   </div>
@@ -43,19 +43,19 @@
         </div>
         <div class="text-center ds-flex-cell ds-edit-cell">
           <div class="btn-group edit-field">
-            <button class="btn btn-outline-success btn-sm ng-star-inserted" ngbTooltip="Confirm changes"
+            <button class="btn btn-outline-success btn-sm ng-star-inserted" ngbTooltip="{{ dsoType + '.edit.buttons.confirm' | translate }}"
                     [disabled]="!newMdField || (saving$ | async) || (loadingFieldValidation$ | async)" (click)="setMetadataField()">
               <i class="fas fa-check fa-fw"></i>
             </button>
-            <button class="btn btn-outline-danger btn-sm" ngbTooltip="Remove"
+            <button class="btn btn-outline-danger btn-sm" ngbTooltip="{{ dsoType + '.edit.buttons.remove' | translate }}"
                     [disabled]="true">
               <i class="fas fa-trash-alt fa-fw"></i>
             </button>
-            <button class="btn btn-outline-warning btn-sm" ngbTooltip="Undo changes"
+            <button class="btn btn-outline-warning btn-sm" ngbTooltip="{{ dsoType + '.edit.buttons.undo' | translate }}"
                     [disabled]="(saving$ | async) || (loadingFieldValidation$ | async)" (click)="form.newValue = undefined">
               <i class="fas fa-undo-alt fa-fw"></i>
             </button>
-            <button class="btn btn-outline-secondary ds-drag-handle btn-sm disabled" ngbTooltip="Drag to reorder"
+            <button class="btn btn-outline-secondary ds-drag-handle btn-sm disabled" ngbTooltip="{{ dsoType + '.edit.buttons.drag' | translate }}"
                     [disabled]="true">
               <i class="fas fa-grip-vertical fa-fw"></i>
             </button>
@@ -82,25 +82,25 @@
         </div>
         <div class="text-center ds-flex-cell ds-edit-cell">
           <div class="btn-group edit-field">
-            <button class="btn btn-outline-primary btn-sm ng-star-inserted" ngbTooltip="Edit" *ngIf="!mdValue.editing"
+            <button class="btn btn-outline-primary btn-sm ng-star-inserted" ngbTooltip="{{ dsoType + '.edit.buttons.edit' | translate }}" *ngIf="!mdValue.editing"
                     [disabled]="mdValue.change === DsoEditMetadataChangeTypeEnum.REMOVE || (saving$ | async)" (click)="mdValue.editing = true">
               <i class="fas fa-edit fa-fw"></i>
             </button>
-            <button class="btn btn-outline-success btn-sm ng-star-inserted" ngbTooltip="Confirm changes" *ngIf="mdValue.editing"
+            <button class="btn btn-outline-success btn-sm ng-star-inserted" ngbTooltip="{{ dsoType + '.edit.buttons.confirm' | translate }}" *ngIf="mdValue.editing"
                     [disabled]="(saving$ | async)" (click)="mdValue.confirmChanges(); onValueSaved()">
               <i class="fas fa-check fa-fw"></i>
             </button>
-            <button class="btn btn-outline-danger btn-sm" ngbTooltip="Remove"
+            <button class="btn btn-outline-danger btn-sm" ngbTooltip="{{ dsoType + '.edit.buttons.remove' | translate }}"
                     [disabled]="mdValue.change || mdValue.editing || (saving$ | async)" (click)="mdValue.change = DsoEditMetadataChangeTypeEnum.REMOVE; onValueSaved()">
               <i class="fas fa-trash-alt fa-fw"></i>
             </button>
-            <button class="btn btn-outline-warning btn-sm" ngbTooltip="Undo changes"
+            <button class="btn btn-outline-warning btn-sm" ngbTooltip="{{ dsoType + '.edit.buttons.undo' | translate }}"
                     [disabled]="(!mdValue.change && !mdValue.editing) || (saving$ | async)" (click)="mdValue.change === DsoEditMetadataChangeTypeEnum.ADD ? form.remove(mdField, idx) : mdValue.discard(); onValueSaved()">
               <i class="fas fa-undo-alt fa-fw"></i>
             </button>
             <!-- TODO: Enable drag -->
             <button class="btn btn-outline-secondary ds-drag-handle btn-sm"
-                    [ngClass]="{'disabled': form.fields[mdField].length === 1 || (saving$ | async)}" ngbTooltip="Drag to reorder" [disabled]="form.fields[mdField].length === 1 || (saving$ | async)">
+                    [ngClass]="{'disabled': form.fields[mdField].length === 1 || (saving$ | async)}" ngbTooltip="{{ dsoType + '.edit.buttons.drag' | translate }}" [disabled]="form.fields[mdField].length === 1 || (saving$ | async)">
               <i class="fas fa-grip-vertical fa-fw"></i>
             </button>
           </div>

src/app/dso-shared/dso-edit-metadata/dso-edit-metadata.component.ts

@@ -1,28 +1,22 @@
 import { Component, Injector, Input, OnDestroy, OnInit, ViewChild } from '@angular/core';
 import { AlertType } from '../../shared/alert/aletr-type';
 import { DSpaceObject } from '../../core/shared/dspace-object.model';
-import { DsoEditMetadataChangeType, DsoEditMetadataForm, DsoEditMetadataValue } from './dso-edit-metadata-form';
+import { DsoEditMetadataChangeType, DsoEditMetadataForm } from './dso-edit-metadata-form';
-import { map, switchMap } from 'rxjs/operators';
+import { map } from 'rxjs/operators';
 import { ActivatedRoute, Data } from '@angular/router';
 import { combineLatest as observableCombineLatest } from 'rxjs/internal/observable/combineLatest';
 import { Subscription } from 'rxjs/internal/Subscription';
 import { RemoteData } from '../../core/data/remote-data';
 import { hasNoValue, hasValue } from '../../shared/empty.util';
-import { RegistryService } from '../../core/registry/registry.service';
 import { BehaviorSubject } from 'rxjs/internal/BehaviorSubject';
-import { Observable } from 'rxjs/internal/Observable';
-import { followLink } from '../../shared/utils/follow-link-config.model';
 import {
   getFirstCompletedRemoteData,
-  getFirstSucceededRemoteData,
-  metadataFieldsToString
 } from '../../core/shared/operators';
 import { UpdateDataService } from '../../core/data/update-data.service';
 import { getDataServiceFor } from '../../core/cache/builders/build-decorators';
 import { ResourceType } from '../../core/shared/resource-type';
 import { NotificationsService } from '../../shared/notifications/notifications.service';
 import { TranslateService } from '@ngx-translate/core';
-import { DataService } from '../../core/data/data.service';
 import { MetadataFieldSelectorComponent } from './metadata-field-selector/metadata-field-selector.component';
 
 @Component({
@@ -30,19 +24,56 @@ import { MetadataFieldSelectorComponent } from './metadata-field-selector/metada
   styleUrls: ['./dso-edit-metadata.component.scss'],
   templateUrl: './dso-edit-metadata.component.html',
 })
+/**
+ * Component showing a table of all metadata on a DSpaceObject and options to modify them
+ */
 export class DsoEditMetadataComponent implements OnInit, OnDestroy {
+  /**
+   * DSpaceObject to edit metadata for
+   */
   @Input() dso: DSpaceObject;
+
+  /**
+   * Reference to the component responsible for showing a metadata-field selector
+   * Used to validate its contents (existing metadata field) before adding a new metadata value
+   */
   @ViewChild(MetadataFieldSelectorComponent) metadataFieldSelectorComponent: MetadataFieldSelectorComponent;
+
+  /**
+   * Resolved update data-service for the given DSpaceObject (depending on its type, e.g. ItemDataService for an Item)
+   * Used to send the PATCH request
+   */
   updateDataService: UpdateDataService<DSpaceObject>;
+
+  /**
+   * Type of the DSpaceObject in String
+   * Used to resolve i18n messages
+   */
   dsoType: string;
 
+  /**
+   * A dynamic form object containing all information about the metadata and the changes made to them, see {@link DsoEditMetadataForm}
+   */
   form: DsoEditMetadataForm;
+
+  /**
+   * The metadata field entered by the user for a new metadata value
+   */
   newMdField: string;
 
+  // Properties determined by the state of the dynamic form, updated by onValueSaved()
   isReinstatable: boolean;
   hasChanges: boolean;
   isEmpty: boolean;
+
+  /**
+   * Whether or not the form is currently being submitted
+   */
   saving$: BehaviorSubject<boolean> = new BehaviorSubject<boolean>(false);
+
+  /**
+   * Whether or not the metadata field is currently being validated
+   */
   loadingFieldValidation$: BehaviorSubject<boolean> = new BehaviorSubject<boolean>(false);
 
   /**
@@ -57,6 +88,10 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
    */
   public DsoEditMetadataChangeTypeEnum = DsoEditMetadataChangeType;
 
+  /**
+   * Subscription for updating the current DSpaceObject
+   * Unsubscribed from in ngOnDestroy()
+   */
   dsoUpdateSubscription: Subscription;
 
   constructor(protected route: ActivatedRoute,
@@ -65,6 +100,10 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
               protected parentInjector: Injector) {
   }
 
+  /**
+   * Read the route (or parent route)'s data to retrieve the current DSpaceObject
+   * After it's retrieved, initialise the data-service and form
+   */
   ngOnInit(): void {
     if (hasNoValue(this.dso)) {
       this.dsoUpdateSubscription = observableCombineLatest([this.route.data, this.route.parent.data]).pipe(
@@ -81,6 +120,9 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
     }
   }
 
+  /**
+   * Initialise (resolve) the data-service for the current DSpaceObject
+   */
   initDataService(): void {
     let type: ResourceType;
     if (typeof this.dso.type === 'string') {
@@ -96,17 +138,29 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
     this.dsoType = type.value;
   }
 
+  /**
+   * Initialise the dynamic form object by passing the DSpaceObject's metadata
+   * Call onValueSaved() to update the form's state properties
+   */
   initForm(): void {
     this.form = new DsoEditMetadataForm(this.dso.metadata);
     this.onValueSaved();
   }
 
+  /**
+   * Update the form's state properties
+   */
   onValueSaved(): void {
     this.hasChanges = this.form.hasChanges();
     this.isReinstatable = this.form.isReinstatable();
     this.isEmpty = Object.keys(this.form.fields).length === 0;
   }
 
+  /**
+   * Submit the current changes to the form by retrieving json PATCH operations from the form and sending it to the
+   * DSpaceObject's data-service
+   * Display notificiations and reset the form afterwards if successful
+   */
   submit(): void {
     this.saving$.next(true);
     this.updateDataService.patch(this.dso, this.form.getOperations()).pipe(
@@ -114,15 +168,23 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
     ).subscribe((rd: RemoteData<DSpaceObject>) => {
       this.saving$.next(false);
       if (rd.hasFailed) {
-        this.notificationsService.error('error', rd.errorMessage);
+        this.notificationsService.error(this.translateService.instant(`${this.dsoType}.edit.metadata.notifications.error.title`), rd.errorMessage);
       } else {
-        this.notificationsService.success('saved', 'saved');
+        this.notificationsService.success(
+            this.translateService.instant(`${this.dsoType}.edit.metadata.notifications.saved.title`),
+            this.translateService.instant(`${this.dsoType}.edit.metadata.notifications.saved.content`)
+        );
         this.dso = rd.payload;
         this.initForm();
       }
     });
   }
 
+  /**
+   * Set the metadata field of the temporary added new metadata value
+   * This will move the new value to its respective parent metadata field
+   * Validate the metadata field first
+   */
   setMetadataField() {
     this.loadingFieldValidation$.next(true);
     this.metadataFieldSelectorComponent.validate().subscribe((valid) => {
@@ -134,21 +196,33 @@ export class DsoEditMetadataComponent implements OnInit, OnDestroy {
     });
   }
 
+  /**
+   * Add a new temporary metadata value
+   */
   add(): void {
     this.newMdField = undefined;
     this.form.add();
   }
 
+  /**
+   * Discard all changes within the current form
+   */
   discard(): void {
     this.form.discard();
     this.onValueSaved();
   }
 
+  /**
+   * Restore any changes previously discarded from the form
+   */
   reinstate(): void {
     this.form.reinstate();
     this.onValueSaved();
   }
 
+  /**
+   * Unsubscribe from any open subscriptions
+   */
   ngOnDestroy() {
     if (hasValue(this.dsoUpdateSubscription)) {
       this.dsoUpdateSubscription.unsubscribe();

src/app/dso-shared/dso-edit-metadata/metadata-field-selector/metadata-field-selector.component.html

@@ -6,7 +6,7 @@
          (focusin)="query$.next(mdField)"
          (dsClickOutside)="query$.next(null)"
          (click)="$event.stopPropagation();" />
-  <div class="invalid-feedback show-feedback" *ngIf="showInvalid">Invalid metadata field, please pick an existing one from the suggestions when searching</div>
+  <div class="invalid-feedback show-feedback" *ngIf="showInvalid">{{ dsoType + '.edit.metadata.metadatafield.invalid' | translate }}</div>
   <div class="autocomplete dropdown-menu" [ngClass]="{'show': (mdFieldOptions$ | async)?.length > 0}">
     <div class="dropdown-list">
       <div *ngFor="let mdFieldOption of (mdFieldOptions$ | async)">

src/app/dso-shared/dso-edit-metadata/metadata-field-selector/metadata-field-selector.component.ts

@@ -12,14 +12,14 @@ import {
 import { switchMap, debounceTime, distinctUntilChanged, map, tap, take } from 'rxjs/operators';
 import { followLink } from '../../../shared/utils/follow-link-config.model';
 import {
-  getAllSucceededRemoteData, getFirstCompletedRemoteData, getFirstSucceededRemoteData,
+  getAllSucceededRemoteData, getFirstSucceededRemoteData,
   metadataFieldsToString
 } from '../../../core/shared/operators';
 import { Observable } from 'rxjs/internal/Observable';
 import { RegistryService } from '../../../core/registry/registry.service';
 import { FormControl } from '@angular/forms';
 import { BehaviorSubject } from 'rxjs/internal/BehaviorSubject';
-import { hasValue, isNotEmpty } from '../../../shared/empty.util';
+import { hasValue } from '../../../shared/empty.util';
 import { Subscription } from 'rxjs/internal/Subscription';
 
 @Component({
@@ -27,25 +27,83 @@ import { Subscription } from 'rxjs/internal/Subscription';
   styleUrls: ['./metadata-field-selector.component.scss'],
   templateUrl: './metadata-field-selector.component.html'
 })
+/**
+ * Component displaying a searchable input for metadata-fields
+ */
 export class MetadataFieldSelectorComponent implements OnInit, OnDestroy, AfterViewInit {
+  /**
+   * Type of the DSpaceObject
+   * Used to resolve i18n messages
+   */
+  @Input() dsoType: string;
+
+  /**
+   * The currently entered metadata field
+   */
   @Input() mdField: string;
+
+  /**
+   * If true, the input will be automatically focussed upon when the component is first loaded
+   */
   @Input() autofocus = false;
+
+  /**
+   * Emit any changes made to the metadata field
+   * This will only emit after a debounce takes place to avoid constant emits when the user is typing
+   */
   @Output() mdFieldChange = new EventEmitter<string>();
+
+  /**
+   * Reference to the metadata-field's input
+   */
   @ViewChild('mdFieldInput', { static: true }) mdFieldInput: ElementRef;
+
+  /**
+   * List of available metadata field options to choose from, dependent on the current query the user entered
+   * Shows up in a dropdown below the input
+   */
   mdFieldOptions$: Observable<string[]>;
 
+  /**
+   * FormControl for the input
+   */
   public input: FormControl = new FormControl();
 
+  /**
+   * The current query to update mdFieldOptions$ for
+   * This is controlled by a debounce, to avoid too many requests
+   */
   query$: BehaviorSubject<string> = new BehaviorSubject<string>(null);
+
+  /**
+   * The amount of time to debounce the query for (in ms)
+   */
   debounceTime = 300;
+
+  /**
+   * Whether or not the the user just selected a value
+   * This flag avoids the metadata field from updating twice, which would result in the dropdown opening again right after selecting a value
+   */
   selectedValueLoading = false;
+
+  /**
+   * Whether or not to show the invalid feedback
+   * True when validate() is called and the mdField isn't present in the available metadata fields retrieved from the server
+   */
   showInvalid = false;
 
+  /**
+   * Subscriptions to unsubscribe from on destroy
+   */
   subs: Subscription[] = [];
 
   constructor(protected registryService: RegistryService) {
   }
 
+  /**
+   * Subscribe to any changes made to the input, with a debounce and fire a query, as well as emit the change from this component
+   * Update the mdFieldOptions$ depending on the query$ fired by querying the server
+   */
   ngOnInit(): void {
     this.subs.push(
       this.input.valueChanges.pipe(
@@ -75,10 +133,19 @@ export class MetadataFieldSelectorComponent implements OnInit, OnDestroy, AfterV
     );
   }
 
+  /**
+   * Focus the input if autofocus is enabled
+   */
   ngAfterViewInit(): void {
+    if (this.autofocus) {
       this.mdFieldInput.nativeElement.focus();
     }
+  }
 
+  /**
+   * Validate the metadata field to check if it exists on the server and return an observable boolean for success/error
+   * Upon subscribing to the returned observable, the showInvalid flag is updated accordingly to show the feedback under the input
+   */
   validate(): Observable<boolean> {
     return this.registryService.queryMetadataFields(this.mdField, null, true, false, followLink('schema')).pipe(
       getFirstSucceededRemoteData(),
@@ -89,11 +156,18 @@ export class MetadataFieldSelectorComponent implements OnInit, OnDestroy, AfterV
     );
   }
 
+  /**
+   * Select a metadata field from the dropdown optipons
+   * @param mdFieldOption
+   */
   select(mdFieldOption: string) {
     this.selectedValueLoading = true;
     this.input.setValue(mdFieldOption);
   }
 
+  /**
+   * Unsubscribe from any open subscriptions
+   */
   ngOnDestroy(): void {
     this.subs.filter((sub) => hasValue(sub)).forEach((sub) => sub.unsubscribe());
   }

src/app/item-page/edit-item-page/edit-item-page.routing.module.ts

@@ -7,7 +7,6 @@ import { ItemPrivateComponent } from './item-private/item-private.component';
 import { ItemPublicComponent } from './item-public/item-public.component';
 import { ItemDeleteComponent } from './item-delete/item-delete.component';
 import { ItemStatusComponent } from './item-status/item-status.component';
-import { ItemMetadataComponent } from './item-metadata/item-metadata.component';
 import { ItemBitstreamsComponent } from './item-bitstreams/item-bitstreams.component';
 import { ItemCollectionMapperComponent } from './item-collection-mapper/item-collection-mapper.component';
 import { ItemMoveComponent } from './item-move/item-move.component';

src/assets/i18n/en.json5

@@ -1791,6 +1791,10 @@
 
   "item.edit.metadata.discard-button": "Discard",
 
+  "item.edit.metadata.edit.buttons.confirm": "Confirm",
+
+  "item.edit.metadata.edit.buttons.drag": "Drag to reorder",
+
   "item.edit.metadata.edit.buttons.edit": "Edit",
 
   "item.edit.metadata.edit.buttons.remove": "Remove",