Merge pull request #2582 from dpalou/MOBILE-3565

Mobile 3565

package-lock.json

@@ -6454,7 +6454,7 @@
       "integrity": "sha512-EYC5eQFVkoYXq39l7tYKE6lEjHJ04mvTmKXxGL7quHLdFPfJMNzru/UYpn92AOfpl3PQaZmou78C7EgmFOwFQQ=="
     },
     "cordova-plugin-wkuserscript": {
-      "version": "git+https://github.com/moodlemobile/cordova-plugin-wkuserscript.git#6413f4bb3c2565f353e690b5c1450b69ad9e860e",
+      "version": "git+https://github.com/moodlemobile/cordova-plugin-wkuserscript.git#aa77d0f98a3fb106f2e798e5adf5882f01a2c947",
       "from": "git+https://github.com/moodlemobile/cordova-plugin-wkuserscript.git"
     },
     "cordova-plugin-wkwebview-cookies": {

src/app/app.component.ts

@@ -16,7 +16,8 @@ import { Component, OnInit } from '@angular/core';
 import { NavController } from '@ionic/angular';
 
 import { CoreLangProvider } from '@services/lang';
-import { CoreEvents } from '@singletons/events';
+import { CoreLoginHelperProvider } from '@core/login/services/helper';
+import { CoreEvents, CoreEventSessionExpiredData } from '@singletons/events';
 
 @Component({
     selector: 'app-root',
@@ -28,6 +29,7 @@ export class AppComponent implements OnInit {
     constructor(
         protected langProvider: CoreLangProvider,
         protected navCtrl: NavController,
+        protected loginHelper: CoreLoginHelperProvider,
     ) {
     }
 
@@ -46,6 +48,11 @@ export class AppComponent implements OnInit {
             // @todo
             // this.removeVersionClass();
         });
+
+        // Listen for session expired events.
+        CoreEvents.on(CoreEvents.SESSION_EXPIRED, (data: CoreEventSessionExpiredData) => {
+            this.loginHelper.sessionExpired(data);
+        });
     }
 
 }

src/app/components/input-errors/core-input-errors.html

@@ -2,12 +2,12 @@
     <ng-container *ngIf="control && control.dirty && !control.valid">
         <ng-container *ngFor="let error of errorKeys">
             <div *ngIf="control.hasError(error)" class="core-input-error">
-                <span *ngIf="errorMessages[error]">{{errorMessages[error]}}</span>
+                <span *ngIf="errorMessages && errorMessages[error]">{{errorMessages[error]}}</span>
-                <span *ngIf="!errorMessages[error] && error == 'max' && control.errors.max">
+                <span *ngIf="(!errorMessages || !errorMessages[error]) && error == 'max' && control.errors?.max">
-                    {{ 'core.login.invalidvaluemax' | translate:{$a: control.errors.max.max} }}
+                    {{ 'core.login.invalidvaluemax' | translate:{$a: control.errors!.max.max} }}
                 </span>
-                <span *ngIf="!errorMessages[error] && error == 'min' && control.errors.min">
+                <span *ngIf="(!errorMessages || !errorMessages[error]) && error == 'min' && control.errors?.min">
-                    {{ 'core.login.invalidvaluemin' | translate:{$a: control.errors.min.min} }}
+                    {{ 'core.login.invalidvaluemin' | translate:{$a: control.errors!.min.min} }}
                 </span>
             </div>
         </ng-container>

src/app/core/login/login-routing.module.ts

@@ -39,21 +39,25 @@ const routes: Routes = [
     },
     {
         path: 'forgottenpassword',
-        loadChildren: () => import('./pages/forgotten-password/forgotten-password.module')
+        loadChildren: () => import('./pages/forgotten-password/forgotten-password.page.module')
             .then( m => m.CoreLoginForgottenPasswordPageModule),
     },
     {
         path: 'changepassword',
-        loadChildren: () => import('./pages/change-password/change-password.module')
+        loadChildren: () => import('./pages/change-password/change-password.page.module')
             .then( m => m.CoreLoginChangePasswordPageModule),
     },
     {
         path: 'sitepolicy',
-        loadChildren: () => import('./pages/site-policy/site-policy.module').then( m => m.CoreLoginSitePolicyPageModule),
+        loadChildren: () => import('./pages/site-policy/site-policy.page.module').then( m => m.CoreLoginSitePolicyPageModule),
     },
     {
         path: 'emailsignup',
-        loadChildren: () => import('./pages/email-signup/email-signup.module').then( m => m.CoreLoginEmailSignupPageModule),
+        loadChildren: () => import('./pages/email-signup/email-signup.page.module').then( m => m.CoreLoginEmailSignupPageModule),
+    },
+    {
+        path: 'reconnect',
+        loadChildren: () => import('./pages/reconnect/reconnect.page.module').then( m => m.CoreLoginReconnectPageModule),
     },
 ];
 

src/app/core/login/login.scss

@@ -13,7 +13,7 @@
     }
 
     .core-sitename {
-        font-size: 1.8rem;
+        font-size: 1.2rem;
     }
 
     .core-login-site-logo {

src/app/core/login/pages/credentials/credentials.page.ts

@@ -28,7 +28,7 @@ import { CoreSiteIdentityProvider, CoreSitePublicConfigResponse } from '@classes
 import { CoreEvents } from '@singletons/events';
 
 /**
- * Page that displays a "splash screen" while the app is being initialized.
+ * Page to enter the user credentials.
  */
 @Component({
     selector: 'page-core-login-credentials',
@@ -161,7 +161,7 @@ export class CoreLoginCredentialsPage implements OnInit, OnDestroy {
      */
     protected treatSiteConfig(): void {
         if (this.siteConfig) {
-            this.siteName = CoreConstants.CONFIG.sitename ?? this.siteConfig.sitename;
+            this.siteName = CoreConstants.CONFIG.sitename ? CoreConstants.CONFIG.sitename : this.siteConfig.sitename;
             this.logoUrl = CoreLoginHelper.instance.getLogoUrl(this.siteConfig);
             this.authInstructions = this.siteConfig.authinstructions || Translate.instance.instant('core.login.loginsteps');
 

src/app/core/login/pages/email-signup/email-signup.html

@@ -148,7 +148,7 @@
                 <ion-input type="text" name="nameField" placeholder="{{ 'core.user.' + nameField | translate }}"
                     formControlName="{{nameField}}" autocorrect="off">
                 </ion-input>
-                <core-input-errors [control]="signupForm.controls[nameField]" [errorMessages]="namefieldsErrors[nameField]">
+                <core-input-errors [control]="signupForm.controls[nameField]" [errorMessages]="namefieldsErrors![nameField]">
                 </core-input-errors>
             </ion-item>
             <ion-item class="ion-text-wrap">

src/app/core/login/pages/email-signup/email-signup.page.ts

@@ -337,7 +337,7 @@ export class CoreLoginEmailSignupPage implements OnInit {
     /**
      * Show authentication instructions.
      */
-    protected showAuthInstructions(): void {
+    showAuthInstructions(): void {
         CoreTextUtils.instance.viewText(Translate.instance.instant('core.login.instructions'), this.authInstructions!);
     }
 

src/app/core/login/pages/reconnect/reconnect.html

@@ -0,0 +1,90 @@
+<ion-header>
+    <ion-toolbar>
+        <ion-buttons slot="start">
+            <ion-back-button></ion-back-button>
+        </ion-buttons>
+
+        <ion-title>{{ 'core.login.reconnect' | translate }}</ion-title>
+    </ion-toolbar>
+</ion-header>
+<ion-content>
+    <div class="ion-text-wrap ion-text-center ion-margin-bottom" [ngClass]="{'item-avatar-center': showSiteAvatar}">
+        <ng-container *ngIf="showSiteAvatar">
+            <ion-avatar>
+                <!-- Show user avatar. -->
+                <img [src]="userAvatar" class="avatar" core-external-content [siteId]="siteId" role="presentation"
+                    alt="{{ 'core.pictureof' | translate:{$a: userFullName} }}" onError="this.src='assets/img/user-avatar.png'">
+            </ion-avatar>
+        </ng-container>
+
+        <div class="core-login-site-logo" *ngIf="!showSiteAvatar">
+            <!-- Show site logo or a default image. -->
+            <img *ngIf="logoUrl" [src]="logoUrl" role="presentation" onError="this.src='assets/img/login_logo.png'">
+            <img *ngIf="!logoUrl" src="assets/img/login_logo.png" role="presentation">
+        </div>
+
+        <h6 *ngIf="siteName" class="ion-padding core-sitename">
+            <core-format-text [text]="siteName" [filter]="false"></core-format-text>
+        </h6>
+        <p class="core-siteurl">{{siteUrl}}</p>
+
+        <ion-item *ngIf="!isLoggedOut" class="ion-text-center core-login-reconnect-warning" lines="none">
+            <ion-label color="danger">
+                <ion-icon name="fas-exclamation-circle" slot="start"></ion-icon>
+                {{ 'core.login.reconnectdescription' | translate }}
+            </ion-label>
+        </ion-item>
+    </div>
+    <form ion-list *ngIf="!isOAuth" [formGroup]="credForm" (ngSubmit)="login($event)" class="core-login-form" #reconnectForm>
+        <ion-item class="ion-text-wrap core-username">
+            <ion-label>
+                <p>{{username}}</p>
+            </ion-label>
+        </ion-item>
+        <ion-item class="ion-margin-bottom">
+            <core-show-password [name]="'password'">
+                <ion-input class="core-ioninput-password" name="password" type="password"
+                    placeholder="{{ 'core.login.password' | translate }}" formControlName="password" [clearOnEdit]="false">
+                </ion-input>
+            </core-show-password>
+        </ion-item>
+        <ion-grid class="ion-padding">
+            <ion-row>
+                <ion-col>
+                    <ion-button expand="block" color="light" (click)="cancel($event)">{{ 'core.login.cancel' | translate }}</ion-button>
+                </ion-col>
+                <ion-col>
+                    <ion-button type="submit" expand="block" [disabled]="!credForm.valid">{{ 'core.login.loginbutton' | translate }}</ion-button>
+                </ion-col>
+            </ion-row>
+        </ion-grid>
+    </form>
+
+    <!-- Forgotten password option. -->
+    <ion-list lines="none" *ngIf="showForgottenPassword && !isOAuth" class="core-login-forgotten-password ion-no-padding">
+        <ion-item button class="ion-text-center ion-text-wrap" (click)="forgottenPassword()" detail="false">
+            <ion-label>
+                {{ 'core.login.forgotten' | translate }}
+            </ion-label>
+        </ion-item>
+    </ion-list>
+
+    <!-- Identity providers. -->
+    <ion-list *ngIf="identityProviders && identityProviders.length" class="ion-padding-top core-login-identity-providers">
+        <ion-item class="ion-text-wrap" lines="none">
+            <ion-label><h3 class="item-heading">{{ 'core.login.potentialidps' | translate }}</h3></ion-label>
+        </ion-item>
+        <ion-item button *ngFor="let provider of identityProviders" class="ion-text-wrap core-oauth-icon"
+            (click)="oauthClicked(provider)" title="{{provider.name}}">
+            <img [src]="provider.iconurl" alt="" width="32" height="32" slot="start">
+            <ion-label>{{provider.name}}</ion-label>
+        </ion-item>
+    </ion-list>
+
+    <!-- If OAuth, display cancel button since the form isn't displayed. -->
+    <ion-list *ngIf="isOAuth">
+        <ion-button expand="block" class="ion-margin" color="light" (click)="cancel($event)">
+            {{ 'core.login.cancel' | translate }}
+        </ion-button>
+    </ion-list>
+</ion-content>

src/app/core/login/pages/reconnect/reconnect.page.module.ts

@@ -0,0 +1,50 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import { NgModule } from '@angular/core';
+import { CommonModule } from '@angular/common';
+import { FormsModule, ReactiveFormsModule } from '@angular/forms';
+import { RouterModule, Routes } from '@angular/router';
+import { IonicModule } from '@ionic/angular';
+import { TranslateModule } from '@ngx-translate/core';
+
+import { CoreComponentsModule } from '@components/components.module';
+import { CoreDirectivesModule } from '@directives/directives.module';
+
+import { CoreLoginReconnectPage } from './reconnect.page';
+
+const routes: Routes = [
+    {
+        path: '',
+        component: CoreLoginReconnectPage,
+    },
+];
+
+@NgModule({
+    imports: [
+        RouterModule.forChild(routes),
+        CommonModule,
+        IonicModule,
+        TranslateModule.forChild(),
+        FormsModule,
+        ReactiveFormsModule,
+        CoreComponentsModule,
+        CoreDirectivesModule,
+    ],
+    declarations: [
+        CoreLoginReconnectPage,
+    ],
+    exports: [RouterModule],
+})
+export class CoreLoginReconnectPageModule {}

src/app/core/login/pages/reconnect/reconnect.page.ts

@@ -0,0 +1,245 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import { Component, OnInit, OnDestroy, ViewChild, ElementRef } from '@angular/core';
+import { ActivatedRoute, Params } from '@angular/router';
+import { FormBuilder, FormGroup, Validators } from '@angular/forms';
+import { NavController } from '@ionic/angular';
+
+import { CoreApp } from '@services/app';
+import { CoreSites } from '@services/sites';
+import { CoreDomUtils } from '@services/utils/dom';
+import { CoreUtils } from '@services/utils/utils';
+import { CoreLoginHelper } from '@core/login/services/helper';
+import { CoreSiteIdentityProvider, CoreSitePublicConfigResponse } from '@classes/site';
+import { CoreEvents } from '@singletons/events';
+import { CoreError } from '@classes/errors/error';
+
+/**
+ * Page to enter the user password to reconnect to a site.
+ */
+@Component({
+    selector: 'page-core-login-reconnect',
+    templateUrl: 'reconnect.html',
+    styleUrls: ['../../login.scss'],
+})
+export class CoreLoginReconnectPage implements OnInit, OnDestroy {
+
+    @ViewChild('reconnectForm') formElement?: ElementRef;
+
+    credForm: FormGroup;
+    siteUrl!: string;
+    username!: string;
+    userFullName!: string;
+    userAvatar?: string;
+    siteName!: string;
+    logoUrl?: string;
+    identityProviders?: CoreSiteIdentityProvider[];
+    showForgottenPassword = true;
+    showSiteAvatar = false;
+    isOAuth = false;
+    isLoggedOut: boolean;
+    siteId!: string;
+
+    protected page?: string;
+    protected pageParams?: Params;
+    protected siteConfig?: CoreSitePublicConfigResponse;
+    protected viewLeft = false;
+    protected eventThrown = false;
+
+    constructor(
+        protected navCtrl: NavController,
+        protected fb: FormBuilder,
+        protected route: ActivatedRoute,
+    ) {
+
+        const currentSite = CoreSites.instance.getCurrentSite();
+
+        this.isLoggedOut = !!currentSite?.isLoggedOut();
+        this.credForm = fb.group({
+            password: ['', Validators.required],
+        });
+    }
+
+    /**
+     * Initialize the component.
+     */
+    async ngOnInit(): Promise<void> {
+        const params = this.route.snapshot.queryParams;
+
+        this.siteId = params['siteId'];
+        this.page = params['pageName'];
+        this.pageParams = params['pageParams'];
+
+        try {
+            const site = await CoreSites.instance.getSite(this.siteId);
+
+            if (!site.infos) {
+                throw new CoreError('Invalid site');
+            }
+
+            this.username = site.infos.username;
+            this.userFullName = site.infos.fullname;
+            this.userAvatar = site.infos.userpictureurl;
+            this.siteUrl = site.infos.siteurl;
+            this.siteName = site.getSiteName();
+
+            // If login was OAuth we should only reach this page if the OAuth method ID has changed.
+            this.isOAuth = site.isOAuth();
+
+            // Show logo instead of avatar if it's a fixed site.
+            this.showSiteAvatar = !!this.userAvatar && !CoreLoginHelper.instance.getFixedSites();
+
+            const config = await CoreUtils.instance.ignoreErrors(site.getPublicConfig());
+
+            if (!config) {
+                return;
+            }
+
+            this.siteConfig = config;
+
+            await CoreSites.instance.checkRequiredMinimumVersion(config);
+
+            // Check logoURL if user avatar is not set.
+            if (this.userAvatar.startsWith(this.siteUrl + '/theme/image.php')) {
+                this.showSiteAvatar = false;
+            }
+            this.logoUrl = CoreLoginHelper.instance.getLogoUrl(config);
+
+            this.getDataFromConfig(this.siteConfig);
+        } catch (error) {
+            // Just leave the view.
+            this.cancel();
+        }
+    }
+
+    /**
+     * Component destroyed.
+     */
+    ngOnDestroy(): void {
+        this.viewLeft = true;
+        CoreEvents.trigger(CoreEvents.LOGIN_SITE_UNCHECKED, { config: this.siteConfig }, this.siteId);
+    }
+
+    /**
+     * Get some data (like identity providers) from the site config.
+     *
+     * @param config Config to use.
+     */
+    protected getDataFromConfig(config: CoreSitePublicConfigResponse): void {
+        const disabledFeatures = CoreLoginHelper.instance.getDisabledFeatures(config);
+
+        this.identityProviders = CoreLoginHelper.instance.getValidIdentityProviders(config, disabledFeatures);
+        this.showForgottenPassword = !CoreLoginHelper.instance.isForgottenPasswordDisabled(config);
+
+        if (!this.eventThrown && !this.viewLeft) {
+            this.eventThrown = true;
+            CoreEvents.trigger(CoreEvents.LOGIN_SITE_CHECKED, { config: config });
+        }
+    }
+
+    /**
+     * Cancel reconnect.
+     *
+     * @param e Event.
+     */
+    cancel(e?: Event): void {
+        if (e) {
+            e.preventDefault();
+            e.stopPropagation();
+        }
+
+        CoreSites.instance.logout();
+    }
+
+    /**
+     * Tries to authenticate the user.
+     *
+     * @param e Event.
+     */
+    async login(e: Event): Promise<void> {
+        e.preventDefault();
+        e.stopPropagation();
+
+        CoreApp.instance.closeKeyboard();
+
+        // Get input data.
+        const password = this.credForm.value.password;
+
+        if (!password) {
+            CoreDomUtils.instance.showErrorModal('core.login.passwordrequired', true);
+
+            return;
+        }
+
+        if (!CoreApp.instance.isOnline()) {
+            CoreDomUtils.instance.showErrorModal('core.networkerrormsg', true);
+
+            return;
+        }
+
+        const modal = await CoreDomUtils.instance.showModalLoading();
+
+        try {
+            // Start the authentication process.
+            const data = await CoreSites.instance.getUserToken(this.siteUrl, this.username, password);
+
+            await CoreSites.instance.updateSiteToken(this.siteUrl, this.username, data.token, data.privateToken);
+
+            CoreDomUtils.instance.triggerFormSubmittedEvent(this.formElement, true);
+
+            // Update site info too.
+            await CoreSites.instance.updateSiteInfoByUrl(this.siteUrl, this.username);
+
+            // Reset fields so the data is not in the view anymore.
+            this.credForm.controls['password'].reset();
+
+            // Go to the site initial page.
+            await CoreLoginHelper.instance.goToSiteInitialPage({
+                redirectPage: this.page,
+                redirectParams: this.pageParams,
+            });
+        } catch (error) {
+            CoreLoginHelper.instance.treatUserTokenError(this.siteUrl, error, this.username, password);
+
+            if (error.loggedout) {
+                this.cancel();
+            } else if (error.errorcode == 'forcepasswordchangenotice') {
+                // Reset password field.
+                this.credForm.controls.password.reset();
+            }
+        } finally {
+            modal.dismiss();
+        }
+    }
+
+    /**
+     * Forgotten password button clicked.
+     */
+    forgottenPassword(): void {
+        CoreLoginHelper.instance.forgottenPasswordClicked(this.siteUrl, this.username, this.siteConfig);
+    }
+
+    /**
+     * An OAuth button was clicked.
+     *
+     * @param provider The provider that was clicked.
+     */
+    oauthClicked(provider: CoreSiteIdentityProvider): void {
+        if (!CoreLoginHelper.instance.openBrowserForOAuthLogin(this.siteUrl, provider, this.siteConfig?.launchurl)) {
+            CoreDomUtils.instance.showErrorModal('Invalid data.');
+        }
+    }
+
+}

src/app/core/login/services/helper.ts

@@ -35,6 +35,7 @@ import { makeSingleton, Translate } from '@singletons/core.singletons';
 import { CoreLogger } from '@singletons/logger';
 import { CoreUrl } from '@singletons/url';
 import { NavigationOptions } from '@ionic/angular/providers/nav-controller';
+import { CoreObject } from '@/app/singletons/object';
 
 /**
  * Helper provider that provides some common features regarding authentication.
@@ -126,7 +127,7 @@ export class CoreLoginHelperProvider {
         const currentSite = CoreSites.instance.getCurrentSite();
         const currentPage = CoreApp.instance.getCurrentPage();
 
-        if (!CoreApp.instance.isSSOAuthenticationOngoing() && currentSite?.isLoggedOut() && currentPage == 'login/reconnect') {
+        if (!CoreApp.instance.isSSOAuthenticationOngoing() && currentSite?.isLoggedOut() && currentPage == '/login/reconnect') {
             // User must reauthenticate but he closed the InAppBrowser without doing so, logout him.
             CoreSites.instance.logout();
         }
@@ -1106,14 +1107,11 @@ export class CoreLoginHelperProvider {
                     this.isOpeningReconnect = true;
 
                     await CoreUtils.instance.ignoreErrors(this.navCtrl.navigateRoot('/login/reconnect', {
-                        queryParams: {
+                        queryParams: CoreObject.removeUndefined({
-                            infoSiteUrl: info.siteurl,
+                            siteId,
-                            siteUrl: result.siteUrl,
-                            siteId: siteId,
                             pageName: data.pageName,
                             pageParams: data.params,
-                            siteConfig: result.config,
+                        }),
-                        },
                     }));
 
                     this.isOpeningReconnect = false;

src/app/core/settings/pages/deviceinfo/deviceinfo.page.module.ts

@@ -20,6 +20,7 @@ import { TranslateModule } from '@ngx-translate/core';
 
 import { CoreComponentsModule } from '@components/components.module';
 import { CoreDirectivesModule } from '@directives/directives.module';
+import { CorePipesModule } from '@pipes/pipes.module';
 
 import { CoreSettingsDeviceInfoPage } from './deviceinfo.page';
 
@@ -38,6 +39,7 @@ const routes: Routes = [
         TranslateModule.forChild(),
         CoreComponentsModule,
         CoreDirectivesModule,
+        CorePipesModule,
     ],
     declarations: [
         CoreSettingsDeviceInfoPage,

src/app/services/utils/iframe.ts

@@ -14,7 +14,7 @@
 
 import { Injectable } from '@angular/core';
 import { NavController } from '@ionic/angular';
-import { WKUserScriptWindow, WKUserScriptInjectionTime } from 'cordova-plugin-wkuserscript';
+import { WKUserScriptWindow } from 'cordova-plugin-wkuserscript';
 import { WKWebViewCookiesWindow } from 'cordova-plugin-wkwebview-cookies';
 
 import { CoreApp } from '@services/app';
@@ -470,7 +470,7 @@ export class CoreIframeUtilsProvider {
         userScriptWindow.WKUserScript?.addScript({
             id: 'CoreIframeUtilsRecaptchaScript',
             file: recaptchaPath,
-            injectionTime: WKUserScriptInjectionTime.END,
+            injectionTime: userScriptWindow.WKUserScript?.InjectionTime.END,
         });
 
         // Handle post messages received by iframes.

src/app/singletons/object.ts

@@ -0,0 +1,35 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/**
+ * Singleton with helper functions for objects.
+ */
+export class CoreObject {
+
+    /**
+     * Delete all keys from an object whose value are null or undefined.
+     *
+     * @param object Object to modify.
+     */
+    static removeUndefined<T>(object: T): T {
+        for (const name in object) {
+            if (object[name] === undefined) {
+                delete object[name];
+            }
+        }
+
+        return object;
+    }
+
+}