MOBILE-3689 init: Replace /login/init with guards

src/app/app-routing.module.ts

@@ -26,6 +26,7 @@ import {
 } from '@angular/router';
 
 import { CoreArray } from '@singletons/array';
+import { CoreRedirectGuard } from '@guards/redirect';
 
 /**
  * Build app routes.
@@ -34,7 +35,16 @@ import { CoreArray } from '@singletons/array';
  * @return App routes.
  */
 function buildAppRoutes(injector: Injector): Routes {
-    return CoreArray.flatten(injector.get<Routes[]>(APP_ROUTES, []));
+    const appRoutes = CoreArray.flatten(injector.get<Routes[]>(APP_ROUTES, []));
+
+    return appRoutes.map(route => {
+        route.canLoad = route.canLoad ?? [];
+        route.canActivate = route.canActivate ?? [];
+        route.canLoad.push(CoreRedirectGuard);
+        route.canActivate.push(CoreRedirectGuard);
+
+        return route;
+    });
 }
 
 /**

src/app/app.component.test.ts

@@ -17,17 +17,16 @@ import { Observable } from 'rxjs';
 import { AppComponent } from '@/app/app.component';
 import { CoreApp } from '@services/app';
 import { CoreEvents } from '@singletons/events';
-import { CoreLangProvider } from '@services/lang';
+import { CoreLang, CoreLangProvider } from '@services/lang';
 import { Network, Platform, NgZone } from '@singletons';
 
-import { mock, mockSingleton, renderComponent, RenderConfig } from '@/testing/utils';
+import { mockSingleton, renderComponent } from '@/testing/utils';
 import { CoreNavigator, CoreNavigatorService } from '@services/navigator';
 
 describe('AppComponent', () => {
 
     let langProvider: CoreLangProvider;
     let navigator: CoreNavigatorService;
-    let config: Partial<RenderConfig>;
 
     beforeEach(() => {
         mockSingleton(CoreApp, { setStatusBarColor: jest.fn() });
@@ -36,23 +35,18 @@ describe('AppComponent', () => {
         mockSingleton(NgZone, { run: jest.fn() });
 
         navigator = mockSingleton(CoreNavigator, ['navigate']);
-        langProvider = mock<CoreLangProvider>(['clearCustomStrings']);
+        langProvider = mockSingleton(CoreLang, ['clearCustomStrings']);
-        config = {
-            providers: [
-                { provide: CoreLangProvider, useValue: langProvider },
-            ],
-        };
     });
 
     it('should render', async () => {
-        const fixture = await renderComponent(AppComponent, config);
+        const fixture = await renderComponent(AppComponent);
 
         expect(fixture.debugElement.componentInstance).toBeTruthy();
         expect(fixture.nativeElement.querySelector('ion-router-outlet')).toBeTruthy();
     });
 
     it('cleans up on logout', async () => {
-        const fixture = await renderComponent(AppComponent, config);
+        const fixture = await renderComponent(AppComponent);
 
         fixture.componentInstance.ngOnInit();
         CoreEvents.trigger(CoreEvents.LOGOUT);
@@ -61,6 +55,4 @@ describe('AppComponent', () => {
         expect(navigator.navigate).toHaveBeenCalledWith('/login/sites', { reset: true });
     });
 
-    it.todo('shows loading while app isn\'t ready');
-
 });

src/app/app.component.ts

@@ -12,10 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { Component, OnInit } from '@angular/core';
+import { AfterViewInit, Component, OnInit, ViewChild } from '@angular/core';
+import { IonRouterOutlet } from '@ionic/angular';
 
-import { CoreLangProvider } from '@services/lang';
+import { CoreLang } from '@services/lang';
-import { CoreLoginHelperProvider } from '@features/login/services/login-helper';
+import { CoreLoginHelper } from '@features/login/services/login-helper';
 import {
     CoreEvents,
     CoreEventSessionExpiredData,
@@ -23,23 +24,20 @@ import {
     CoreEventSiteData,
     CoreEventSiteUpdatedData,
 } from '@singletons/events';
-import { Network, NgZone, Platform } from '@singletons';
+import { Network, NgZone, Platform, SplashScreen } from '@singletons';
 import { CoreApp } from '@services/app';
 import { CoreSites } from '@services/sites';
 import { CoreNavigator } from '@services/navigator';
+import { CoreSubscriptions } from '@singletons/subscriptions';
 
 @Component({
     selector: 'app-root',
     templateUrl: 'app.component.html',
     styleUrls: ['app.component.scss'],
 })
-export class AppComponent implements OnInit {
+export class AppComponent implements OnInit, AfterViewInit {
 
-    constructor(
+    @ViewChild(IonRouterOutlet) outlet?: IonRouterOutlet;
-        protected langProvider: CoreLangProvider,
-        protected loginHelper: CoreLoginHelperProvider,
-    ) {
-    }
 
     /**
      * Component being initialized.
@@ -58,7 +56,7 @@ export class AppComponent implements OnInit {
             CoreNavigator.instance.navigate('/login/sites', { reset: true });
 
             // Unload lang custom strings.
-            this.langProvider.clearCustomStrings();
+            CoreLang.instance.clearCustomStrings();
 
             // Remove version classes from body.
             this.removeVersionClass();
@@ -66,20 +64,20 @@ export class AppComponent implements OnInit {
 
         // Listen for session expired events.
         CoreEvents.on(CoreEvents.SESSION_EXPIRED, (data: CoreEventSessionExpiredData) => {
-            this.loginHelper.sessionExpired(data);
+            CoreLoginHelper.instance.sessionExpired(data);
         });
 
         // Listen for passwordchange and usernotfullysetup events to open InAppBrowser.
         CoreEvents.on(CoreEvents.PASSWORD_CHANGE_FORCED, (data: CoreEventSiteData) => {
-            this.loginHelper.passwordChangeForced(data.siteId!);
+            CoreLoginHelper.instance.passwordChangeForced(data.siteId!);
         });
         CoreEvents.on(CoreEvents.USER_NOT_FULLY_SETUP, (data: CoreEventSiteData) => {
-            this.loginHelper.openInAppForEdit(data.siteId!, '/user/edit.php', 'core.usernotfullysetup');
+            CoreLoginHelper.instance.openInAppForEdit(data.siteId!, '/user/edit.php', 'core.usernotfullysetup');
         });
 
         // Listen for sitepolicynotagreed event to accept the site policy.
         CoreEvents.on(CoreEvents.SITE_POLICY_NOT_AGREED, (data: CoreEventSiteData) => {
-            this.loginHelper.sitePolicyNotAgreed(data.siteId);
+            CoreLoginHelper.instance.sitePolicyNotAgreed(data.siteId);
         });
 
         CoreEvents.on(CoreEvents.LOGIN, async (data: CoreEventSiteData) => {
@@ -119,6 +117,17 @@ export class AppComponent implements OnInit {
         this.onPlatformReady();
     }
 
+    /**
+     * @inheritdoc
+     */
+    ngAfterViewInit(): void {
+        if (!this.outlet) {
+            return;
+        }
+
+        CoreSubscriptions.once(this.outlet.activateEvents, () => SplashScreen.instance.hide());
+    }
+
     /**
      * Async init function on platform ready.
      */
@@ -155,8 +164,9 @@ export class AppComponent implements OnInit {
      */
     protected loadCustomStrings(): void {
         const currentSite = CoreSites.instance.getCurrentSite();
+
         if (currentSite) {
-            this.langProvider.loadCustomStringsFromSite(currentSite);
+            CoreLang.instance.loadCustomStringsFromSite(currentSite);
         }
     }
 

src/core/directives/format-text.ts

@@ -38,6 +38,7 @@ import { CoreLinkDirective } from './link';
 import { CoreFilter, CoreFilterFilter, CoreFilterFormatTextOptions } from '@features/filter/services/filter';
 import { CoreFilterDelegate } from '@features/filter/services/filter-delegate';
 import { CoreFilterHelper } from '@features/filter/services/filter-helper';
+import { CoreSubscriptions } from '@singletons/subscriptions';
 
 /**
  * Directive to format text rendered. It renders the HTML and treats all links and media, using CoreLinkDirective
@@ -567,12 +568,7 @@ export class CoreFormatTextDirective implements OnChanges {
                     return Promise.resolve();
                 }
 
-                return new Promise((resolve): void => {
+                return new Promise(resolve => CoreSubscriptions.once(externalImage.onLoad, resolve));
-                    const subscription = externalImage.onLoad.subscribe(() => {
-                        subscription.unsubscribe();
-                        resolve();
-                    });
-                });
             }));
 
             // Automatically reject the promise after 5 seconds to prevent blocking the user forever.

src/core/features/login/guards/has-sites.ts

@@ -0,0 +1,59 @@
+// (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 { Injectable } from '@angular/core';
+import { CanActivate, CanLoad, UrlTree } from '@angular/router';
+
+import { CoreSites } from '@services/sites';
+import { CoreUtils } from '@services/utils/utils';
+import { Router } from '@singletons';
+
+import { CoreLoginHelper } from '../services/login-helper';
+
+@Injectable({ providedIn: 'root' })
+export class CoreLoginHasSitesGuard implements CanActivate, CanLoad {
+
+    /**
+     * @inheritdoc
+     */
+    canActivate(): Promise<true | UrlTree> {
+        return this.guard();
+    }
+
+    /**
+     * @inheritdoc
+     */
+    canLoad(): Promise<true | UrlTree> {
+        return this.guard();
+    }
+
+    /**
+     * Check if the user has any sites stored.
+     */
+    private async guard(): Promise<true | UrlTree> {
+        const sites = await CoreUtils.instance.ignoreErrors(CoreSites.instance.getSites(), []);
+
+        if (sites.length > 0) {
+            return true;
+        }
+
+        const [path, params] = CoreLoginHelper.instance.getAddSiteRouteInfo();
+        const route = Router.instance.parseUrl(path);
+
+        route.queryParams = params;
+
+        return route;
+    }
+
+}

src/core/features/login/login-lazy.module.ts

@@ -21,16 +21,13 @@ import { TranslateModule } from '@ngx-translate/core';
 import { CoreSharedModule } from '@/core/shared.module';
 import { CoreLoginSiteHelpComponent } from './components/site-help/site-help';
 import { CoreLoginSiteOnboardingComponent } from './components/site-onboarding/site-onboarding';
+import { CoreLoginHasSitesGuard } from './guards/has-sites';
 
 const routes: Routes = [
     {
         path: '',
-        redirectTo: 'init',
         pathMatch: 'full',
-    },
+        redirectTo: 'sites',
-    {
-        path: 'init',
-        loadChildren: () => import('./pages/init/init.module').then( m => m.CoreLoginInitPageModule),
     },
     {
         path: 'site',
@@ -43,6 +40,8 @@ const routes: Routes = [
     {
         path: 'sites',
         loadChildren: () => import('./pages/sites/sites.module').then( m => m.CoreLoginSitesPageModule),
+        canLoad: [CoreLoginHasSitesGuard],
+        canActivate: [CoreLoginHasSitesGuard],
     },
     {
         path: 'forgottenpassword',

src/core/features/login/pages/init/init.html

@@ -1,7 +0,0 @@
-<ion-content fullscreen="true" scrollY="false">
-    <div class="core-bglogo" slot="fixed">
-        <div class="core-center-spinner">
-            <ion-spinner></ion-spinner>
-        </div>
-    </div>
-</ion-content>

src/core/features/login/pages/init/init.scss

@@ -1,25 +0,0 @@
-ion-content::part(background) {
-    --background: var(--core-splash-screen-background, #ffffff);
-
-    background-image: url("~@/assets/img/splash.png");
-    background-repeat: no-repeat;
-    background-size: 100%;
-    background-size: var(--core-splash-bgsize, 100vmax);
-    background-position: center;
-}
-
-.core-bglogo {
-    display: table;
-    width: 100%;
-    height: 100%;
-
-    .core-center-spinner {
-        display: table-cell;
-        vertical-align: middle;
-        text-align: center;
-    }
-
-    ion-spinner {
-        --color: var(--core-splash-spinner-color, var(--core-color));
-    }
-}

src/core/features/login/pages/init/init.ts

@@ -1,125 +0,0 @@
-// (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 } from '@angular/core';
-
-import { CoreApp, CoreRedirectData } from '@services/app';
-import { ApplicationInit, SplashScreen } from '@singletons';
-import { CoreConstants } from '@/core/constants';
-import { CoreSites } from '@services/sites';
-import { CoreLoginHelper } from '@features/login/services/login-helper';
-import { CoreNavigator } from '@services/navigator';
-
-/**
- * Page that displays a "splash screen" while the app is being initialized.
- */
-@Component({
-    selector: 'page-core-login-init',
-    templateUrl: 'init.html',
-    styleUrls: ['init.scss'],
-})
-export class CoreLoginInitPage implements OnInit {
-
-    // @todo this page should be removed in favor of native splash
-    // or a splash component rendered in the root app component
-
-    /**
-     * Initialize the component.
-     */
-    async ngOnInit(): Promise<void> {
-        // Wait for the app to be ready.
-        await ApplicationInit.instance.donePromise;
-
-        // Check if there was a pending redirect.
-        const redirectData = CoreApp.instance.getRedirect();
-
-        if (redirectData.siteId) {
-            await this.handleRedirect(redirectData);
-        } else {
-            await this.loadPage();
-        }
-
-        // If we hide the splash screen now, the init view is still seen for an instant. Wait a bit to make sure it isn't seen.
-        setTimeout(() => {
-            SplashScreen.instance.hide();
-        }, 100);
-    }
-
-    /**
-     * Treat redirect data.
-     *
-     * @param redirectData Redirect data.
-     */
-    protected async handleRedirect(redirectData: CoreRedirectData): Promise<void> {
-        // Unset redirect data.
-        CoreApp.instance.storeRedirect('', '', {});
-
-        // Only accept the redirect if it was stored less than 20 seconds ago.
-        if (redirectData.timemodified && Date.now() - redirectData.timemodified < 20000) {
-            if (redirectData.siteId != CoreConstants.NO_SITE_ID) {
-                // The redirect is pointing to a site, load it.
-                try {
-                    const loggedIn = await CoreSites.instance.loadSite(
-                        redirectData.siteId!,
-                        redirectData.page,
-                        redirectData.params,
-                    );
-
-                    if (!loggedIn) {
-                        return;
-                    }
-
-                    await CoreNavigator.instance.navigateToSiteHome({
-                        params: {
-                            redirectPath: redirectData.page,
-                            redirectParams: redirectData.params,
-                        },
-                    });
-
-                    return;
-                } catch (error) {
-                    // Site doesn't exist.
-                    return this.loadPage();
-                }
-            } else if (redirectData.page) {
-                // No site to load, open the page.
-                // @todo return CoreNavigator.instance.goToNoSitePage(redirectData.page, redirectData.params);
-            }
-        }
-
-        return this.loadPage();
-    }
-
-    /**
-     * Load the right page.
-     *
-     * @return Promise resolved when done.
-     */
-    protected async loadPage(): Promise<void> {
-        if (CoreSites.instance.isLoggedIn()) {
-            if (CoreLoginHelper.instance.isSiteLoggedOut()) {
-                await CoreSites.instance.logout();
-
-                return this.loadPage();
-            }
-
-            await CoreNavigator.instance.navigateToSiteHome();
-
-            return;
-        }
-
-        await CoreNavigator.instance.navigate('/login/sites', { reset: true });
-    }
-
-}

src/core/features/login/pages/sites/sites.ts

@@ -45,13 +45,7 @@ export class CoreLoginSitesPage implements OnInit {
      * @return Promise resolved when done.
      */
     async ngOnInit(): Promise<void> {
-        const sites = await CoreUtils.instance.ignoreErrors(CoreSites.instance.getSortedSites());
+        const sites = await CoreUtils.instance.ignoreErrors(CoreSites.instance.getSortedSites(), [] as CoreSiteBasicInfo[]);
-
-        if (!sites || sites.length == 0) {
-            CoreLoginHelper.instance.goToAddSite(true);
-
-            return;
-        }
 
         // Remove protocol from the url to show more url text.
         this.sites = sites.map((site) => {

src/core/features/login/services/login-helper.ts

@@ -34,6 +34,7 @@ import { makeSingleton, Translate } from '@singletons';
 import { CoreLogger } from '@singletons/logger';
 import { CoreUrl } from '@singletons/url';
 import { CoreNavigator } from '@services/navigator';
+import { CoreObject } from '@singletons/object';
 
 /**
  * Helper provider that provides some common features regarding authentication.
@@ -408,22 +409,27 @@ export class CoreLoginHelperProvider {
      * @return Promise resolved when done.
      */
     async goToAddSite(setRoot?: boolean, showKeyboard?: boolean): Promise<void> {
-        let pageRoute: string;
+        const [path, params] = this.getAddSiteRouteInfo(showKeyboard);
-        let params: Params;
 
+        await CoreNavigator.instance.navigate(path, { params, reset: setRoot });
+    }
+
+    /**
+     * Get path and params to visit the route to add site.
+     *
+     * @param showKeyboard Whether to show keyboard in the new page. Only if no fixed URL set.
+     * @return Path and params.
+     */
+    getAddSiteRouteInfo(showKeyboard?: boolean): [string, Params] {
         if (this.isFixedUrlSet()) {
             // Fixed URL is set, go to credentials page.
             const fixedSites = this.getFixedSites();
             const url = typeof fixedSites == 'string' ? fixedSites : fixedSites[0].url;
 
-            pageRoute = '/login/credentials';
+            return ['/login/credentials', { siteUrl: url }];
-            params = { siteUrl: url };
-        } else {
-            pageRoute = '/login/site';
-            params = { showKeyboard: showKeyboard };
         }
 
-        await CoreNavigator.instance.navigate(pageRoute, { params, reset: setRoot });
+        return ['/login/site', CoreObject.withoutEmpty({ showKeyboard: showKeyboard })];
     }
 
     /**

src/core/features/login/tests/pages/init.test.ts

@@ -1,52 +0,0 @@
-// (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 { CoreApp } from '@services/app';
-import { CoreLoginInitPage } from '@features/login/pages/init/init';
-import { CoreSites } from '@services/sites';
-import { ApplicationInit, SplashScreen } from '@singletons';
-
-import { mockSingleton, renderComponent } from '@/testing/utils';
-import { CoreNavigator, CoreNavigatorService } from '@services/navigator';
-
-describe('CoreLoginInitPage', () => {
-
-    let navigator: CoreNavigatorService;
-
-    beforeEach(() => {
-        mockSingleton(CoreApp, { getRedirect: () => ({}) });
-        mockSingleton(ApplicationInit, { donePromise: Promise.resolve() });
-        mockSingleton(CoreSites, { isLoggedIn: () => false });
-        mockSingleton(SplashScreen, ['hide']);
-
-        navigator = mockSingleton(CoreNavigator, ['navigate']);
-    });
-
-    it('should render', async () => {
-        const fixture = await renderComponent(CoreLoginInitPage, {});
-
-        expect(fixture.debugElement.componentInstance).toBeTruthy();
-        expect(fixture.nativeElement.querySelector('ion-spinner')).toBeTruthy();
-    });
-
-    it('navigates to sites page after loading', async () => {
-        const fixture = await renderComponent(CoreLoginInitPage, {});
-
-        fixture.componentInstance.ngOnInit();
-        await ApplicationInit.instance.donePromise;
-
-        expect(navigator.navigate).toHaveBeenCalledWith('/login/sites', { reset: true });
-    });
-
-});

src/core/features/mainmenu/guards/auth.ts

@@ -13,28 +13,44 @@
 // limitations under the License.
 
 import { Injectable } from '@angular/core';
-import { Router, CanLoad, CanActivate, UrlTree } from '@angular/router';
+import { CanLoad, CanActivate, UrlTree } from '@angular/router';
+import { CoreLoginHelper } from '@features/login/services/login-helper';
 
 import { CoreSites } from '@services/sites';
-import { ApplicationInit } from '@singletons';
+import { Router } from '@singletons';
 
 @Injectable({ providedIn: 'root' })
-export class AuthGuard implements CanLoad, CanActivate {
+export class CoreMainMenuAuthGuard implements CanLoad, CanActivate {
-
-    constructor(private router: Router) {}
 
+    /**
+     * @inheritdoc
+     */
     canActivate(): Promise<true | UrlTree> {
         return this.guard();
     }
 
+    /**
+     * @inheritdoc
+     */
     canLoad(): Promise<true | UrlTree> {
         return this.guard();
     }
 
+    /**
+     * Check if the current user should be redirected to the authentication page.
+     */
     private async guard(): Promise<true | UrlTree> {
-        await ApplicationInit.instance.donePromise;
+        if (!CoreSites.instance.isLoggedIn()) {
+            return Router.instance.parseUrl('/login');
+        }
 
-        return CoreSites.instance.isLoggedIn() || this.router.parseUrl('/login');
+        if (CoreLoginHelper.instance.isSiteLoggedOut()) {
+            await CoreSites.instance.logout();
+
+            return Router.instance.parseUrl('/login');
+        }
+
+        return true;
     }
 
 }

src/core/features/mainmenu/mainmenu.module.ts

@@ -14,7 +14,7 @@
 
 import { APP_INITIALIZER, NgModule } from '@angular/core';
 import { Routes } from '@angular/router';
-import { AuthGuard } from '@guards/auth';
+import { CoreMainMenuAuthGuard } from '@features/mainmenu/guards/auth';
 
 import { AppRoutingModule } from '@/app/app-routing.module';
 
@@ -30,8 +30,8 @@ const appRoutes: Routes = [
     {
         path: 'main',
         loadChildren: () => import('./mainmenu-lazy.module').then(m => m.CoreMainMenuLazyModule),
-        canActivate: [AuthGuard],
+        canActivate: [CoreMainMenuAuthGuard],
-        canLoad: [AuthGuard],
+        canLoad: [CoreMainMenuAuthGuard],
     },
 ];
 

src/core/guards/redirect.ts

@@ -0,0 +1,92 @@
+// (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 { Injectable } from '@angular/core';
+import { CanActivate, CanLoad, UrlTree } from '@angular/router';
+import { CoreApp } from '@services/app';
+import { CoreSites } from '@services/sites';
+import { Router } from '@singletons';
+import { CoreObject } from '@singletons/object';
+import { CoreConstants } from '../constants';
+
+@Injectable({ providedIn: 'root' })
+export class CoreRedirectGuard implements CanLoad, CanActivate {
+
+    /**
+     * @inheritdoc
+     */
+    canLoad(): Promise<true | UrlTree> {
+        return this.guard();
+    }
+
+    /**
+     * @inheritdoc
+     */
+    canActivate(): Promise<true | UrlTree> {
+        return this.guard();
+    }
+
+    /**
+     * Check if there is a pending redirect and trigger it.
+     */
+    private async guard(): Promise<true | UrlTree> {
+        const redirect = CoreApp.instance.getRedirect();
+
+        if (!redirect) {
+            return true;
+        }
+
+        try {
+            // Only accept the redirect if it was stored less than 20 seconds ago.
+            if (!redirect.timemodified || Date.now() - redirect.timemodified < 20000) {
+                return true;
+            }
+
+            // Redirect to site path.
+            if (redirect.siteId && redirect.siteId !== CoreConstants.NO_SITE_ID) {
+                const loggedIn = await CoreSites.instance.loadSite(
+                    redirect.siteId,
+                    redirect.page,
+                    redirect.params,
+                );
+                const route = Router.instance.parseUrl('/main');
+
+                route.queryParams = CoreObject.withoutEmpty({
+                    redirectPath: redirect.page,
+                    redirectParams: redirect.params,
+                });
+
+                return loggedIn ? route : true;
+            }
+
+            // Abort redirect.
+            if (!redirect.page) {
+                return true;
+            }
+
+            // Redirect to non-site path.
+            const route = Router.instance.parseUrl(redirect.page);
+
+            route.queryParams = CoreObject.withoutEmpty({
+                redirectPath: redirect.page,
+                redirectParams: redirect.params,
+            });
+
+            return route;
+        } finally {
+            CoreApp.instance.forgetRedirect();
+        }
+    }
+
+}

src/core/initializers/consume-storage-redirect.ts

@@ -12,27 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import { NgModule } from '@angular/core';
+import { CoreApp } from '@services/app';
-import { RouterModule, Routes } from '@angular/router';
-import { IonicModule } from '@ionic/angular';
 
-import { CoreLoginInitPage } from './init';
+export default function(): void {
-
+    CoreApp.instance.consumeStorageRedirect();
-const routes: Routes = [
+}
-    {
-        path: '',
-        component: CoreLoginInitPage,
-    },
-];
-
-@NgModule({
-    imports: [
-        RouterModule.forChild(routes),
-        IonicModule,
-    ],
-    declarations: [
-        CoreLoginInitPage,
-    ],
-    exports: [RouterModule],
-})
-export class CoreLoginInitPageModule {}

src/core/services/app.ts

@@ -25,6 +25,7 @@ import { makeSingleton, Keyboard, Network, StatusBar, Platform, Device } from '@
 import { CoreLogger } from '@singletons/logger';
 import { CoreColors } from '@singletons/colors';
 import { DBNAME, SCHEMA_VERSIONS_TABLE_NAME, SCHEMA_VERSIONS_TABLE_SCHEMA, SchemaVersionsDBEntry } from '@services/database/app';
+import { CoreObject } from '@singletons/object';
 
 /**
  * Object responsible of managing schema versions.
@@ -58,6 +59,7 @@ export class CoreAppProvider {
     protected keyboardClosing = false;
     protected backActions: {callback: () => boolean; priority: number}[] = [];
     protected forceOffline = false;
+    protected redirect?: CoreRedirectData;
 
     // Variables for DB.
     protected schemaVersionsManager: Promise<SchemaVersionsManager>;
@@ -516,32 +518,50 @@ export class CoreAppProvider {
         await deferred.promise;
     }
 
+    /**
+     * Read redirect data from local storage and clear it if it existed.
+     */
+    consumeStorageRedirect(): void {
+        if (!localStorage?.getItem) {
+            return;
+        }
+
+        try {
+            // Read data from storage.
+            const jsonData = localStorage.getItem('CoreRedirect');
+
+            if (!jsonData) {
+                return;
+            }
+
+            // Clear storage.
+            localStorage.removeItem('CoreRedirect');
+
+            // Remember redirect data.
+            const data: CoreRedirectData = JSON.parse(jsonData);
+
+            if (!CoreObject.isEmpty(data)) {
+                this.redirect = data;
+            }
+        } catch (error) {
+            this.logger.error('Error loading redirect data:', error);
+        }
+    }
+
+    /**
+     * Forget redirect data.
+     */
+    forgetRedirect(): void {
+        delete this.redirect;
+    }
+
     /**
      * Retrieve redirect data.
      *
      * @return Object with siteid, state, params and timemodified.
      */
-    getRedirect(): CoreRedirectData {
+    getRedirect(): CoreRedirectData | null {
-        if (localStorage?.getItem) {
+        return this.redirect || null;
-            try {
-                const paramsJson = localStorage.getItem('CoreRedirectParams');
-                const data: CoreRedirectData = {
-                    siteId: localStorage.getItem('CoreRedirectSiteId') || undefined,
-                    page: localStorage.getItem('CoreRedirectState')  || undefined,
-                    timemodified: parseInt(localStorage.getItem('CoreRedirectTime') || '0', 10),
-                };
-
-                if (paramsJson) {
-                    data.params = JSON.parse(paramsJson);
-                }
-
-                return data;
-            } catch (ex) {
-                this.logger.error('Error loading redirect data:', ex);
-            }
-        }
-
-        return {};
     }
 
     /**
@@ -552,17 +572,19 @@ export class CoreAppProvider {
      * @param params Page params.
      */
     storeRedirect(siteId: string, page: string, params: Params): void {
-        if (localStorage && localStorage.setItem) {
         try {
-                localStorage.setItem('CoreRedirectSiteId', siteId);
+            const redirect: CoreRedirectData = {
-                localStorage.setItem('CoreRedirectState', page);
+                siteId,
-                localStorage.setItem('CoreRedirectParams', JSON.stringify(params));
+                page,
-                localStorage.setItem('CoreRedirectTime', String(Date.now()));
+                params,
+                timemodified: Date.now(),
+            };
+
+            localStorage.setItem('CoreRedirect', JSON.stringify(redirect));
         } catch (ex) {
             // Ignore errors.
         }
     }
-    }
 
     /**
      * The back button event is triggered when the user presses the native

src/core/services/lang.ts

@@ -18,6 +18,7 @@ import { CoreConstants } from '@/core/constants';
 import { LangChangeEvent } from '@ngx-translate/core';
 import { CoreAppProvider } from '@services/app';
 import { CoreConfig } from '@services/config';
+import { CoreSubscriptions } from '@singletons/subscriptions';
 import { makeSingleton, Translate, Platform } from '@singletons';
 
 import * as moment from 'moment';
@@ -128,44 +129,25 @@ export class CoreLangProvider {
 
         // Change the language, resolving the promise when we receive the first value.
         promises.push(new Promise((resolve, reject) => {
-            const subscription = Translate.instance.use(language).subscribe((data) => {
+            CoreSubscriptions.once(Translate.instance.use(language), data => {
                 // It's a language override, load the original one first.
                 const fallbackLang = Translate.instance.instant('core.parentlanguage');
 
                 if (fallbackLang != '' && fallbackLang != 'core.parentlanguage' && fallbackLang != language) {
-                    const fallbackSubs = Translate.instance.use(fallbackLang).subscribe((fallbackData) => {
+                    CoreSubscriptions.once(
+                        Translate.instance.use(fallbackLang),
+                        fallbackData => {
                             data = Object.assign(fallbackData, data);
-                        resolve(data);
 
-                        // Data received, unsubscribe. Use a timeout because we can receive a value immediately.
+                            resolve(data);
-                        setTimeout(() => {
+                        },
-                            fallbackSubs.unsubscribe();
-                        });
-                    }, () => {
                         // Resolve with the original language.
-                        resolve(data);
+                        () => resolve(data),
-
+                    );
-                        // Error received, unsubscribe. Use a timeout because we can receive a value immediately.
-                        setTimeout(() => {
-                            fallbackSubs.unsubscribe();
-                        });
-                    });
                 } else {
                     resolve(data);
                 }
-
+            }, reject);
-                // Data received, unsubscribe. Use a timeout because we can receive a value immediately.
-                setTimeout(() => {
-                    subscription.unsubscribe();
-                });
-            }, (error) => {
-                reject(error);
-
-                // Error received, unsubscribe. Use a timeout because we can receive a value immediately.
-                setTimeout(() => {
-                    subscription.unsubscribe();
-                });
-            });
         }));
 
         // Change the config.

src/core/singletons/subscriptions.ts

@@ -0,0 +1,52 @@
+// (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 { EventEmitter } from '@angular/core';
+import { Observable } from 'rxjs';
+
+/**
+ * Subscribable object.
+ */
+type Subscribable<T> = EventEmitter<T> | Observable<T>;
+
+/**
+ * Singleton with helpers to work with subscriptions.
+ */
+export class CoreSubscriptions {
+
+    /**
+     * Listen once to a subscribable object.
+     *
+     * @param subscribable Subscribable to listen to.
+     * @param onSuccess Callback to run when the subscription is updated.
+     * @param onError Callback to run when the an error happens.
+     */
+    static once<T>(subscribable: Subscribable<T>, onSuccess: (value: T) => unknown, onError?: (error: unknown) => unknown): void {
+        const subscription = subscribable.subscribe(
+            value => {
+                // Unsubscribe using a timeout because we can receive a value immediately.
+                setTimeout(() => subscription.unsubscribe(), 0);
+
+                onSuccess(value);
+            },
+            error => {
+                // Unsubscribe using a timeout because we can receive a value immediately.
+                setTimeout(() => subscription.unsubscribe(), 0);
+
+                onError?.call(error);
+            },
+        );
+    }
+
+}