From 3329932d276983bb74171fd51be617757cd241b2 Mon Sep 17 00:00:00 2001
From: Sean Engelhardt <sean.f.t.engelhardt@gmail.com>
Date: Fri, 22 Feb 2019 10:04:50 +0100
Subject: [PATCH] Preloads modules on site component

Adds module preloading on site modules.
---
 client/src/app/app-routing.module.ts         |  6 ++--
 client/src/app/shared/utils/app-preloader.ts | 27 +++++++++++++++++
 client/src/app/site/site-routing.module.ts   | 31 +++++++++++++-------
 3 files changed, 51 insertions(+), 13 deletions(-)
 create mode 100644 client/src/app/shared/utils/app-preloader.ts

diff --git a/client/src/app/app-routing.module.ts b/client/src/app/app-routing.module.ts
index 60260308c..22171a316 100644
--- a/client/src/app/app-routing.module.ts
+++ b/client/src/app/app-routing.module.ts
@@ -7,6 +7,7 @@ import { LoginLegalNoticeComponent } from './site/login/components/login-legal-n
 import { LoginPrivacyPolicyComponent } from './site/login/components/login-privacy-policy/login-privacy-policy.component';
 import { ResetPasswordComponent } from './site/login/components/reset-password/reset-password.component';
 import { ResetPasswordConfirmComponent } from './site/login/components/reset-password-confirm/reset-password-confirm.component';
+import { AppPreloader } from './shared/utils/app-preloader';
 
 /**
  * Global app routing
@@ -29,7 +30,8 @@ const routes: Routes = [
 ];
 
 @NgModule({
-    imports: [RouterModule.forRoot(routes)],
-    exports: [RouterModule]
+    imports: [RouterModule.forRoot(routes, { preloadingStrategy: AppPreloader })],
+    exports: [RouterModule],
+    providers: [AppPreloader]
 })
 export class AppRoutingModule {}
diff --git a/client/src/app/shared/utils/app-preloader.ts b/client/src/app/shared/utils/app-preloader.ts
new file mode 100644
index 000000000..798a3d39e
--- /dev/null
+++ b/client/src/app/shared/utils/app-preloader.ts
@@ -0,0 +1,27 @@
+import { PreloadingStrategy, Route } from '@angular/router';
+import { Observable, of } from 'rxjs';
+
+/**
+ * Custom preload strategy class
+ *
+ * @example
+ * ```
+ * {
+ *    path: 'agenda',
+ *    loadChildren: './agenda/agenda.module#AgendaModule',
+ *    data: { preload: true }
+ * }
+ * ```
+ */
+export class AppPreloader implements PreloadingStrategy {
+    /**
+     * Custom preload function.
+     * Can be add to routes as data argument.
+     *
+     * @param route The route to load
+     * @param load The load function
+     */
+    public preload(route: Route, load: Function): Observable<any> {
+        return route.data && route.data.preload ? load() : of(null);
+    }
+}
diff --git a/client/src/app/site/site-routing.module.ts b/client/src/app/site/site-routing.module.ts
index 4b56f5694..b5a21c703 100644
--- a/client/src/app/site/site-routing.module.ts
+++ b/client/src/app/site/site-routing.module.ts
@@ -2,7 +2,6 @@ import { NgModule } from '@angular/core';
 import { Routes, RouterModule } from '@angular/router';
 
 import { SiteComponent } from './site.component';
-
 import { AuthGuard } from '../core/core-services/auth-guard.service';
 
 /**
@@ -17,43 +16,53 @@ const routes: Routes = [
         children: [
             {
                 path: '',
-                loadChildren: './common/common.module#CommonModule'
+                loadChildren: './common/common.module#CommonModule',
+                data: { preload: true }
             },
             {
                 path: 'agenda',
-                loadChildren: './agenda/agenda.module#AgendaModule'
+                loadChildren: './agenda/agenda.module#AgendaModule',
+                data: { preload: true }
             },
             {
                 path: 'assignments',
-                loadChildren: './assignments/assignments.module#AssignmentsModule'
+                loadChildren: './assignments/assignments.module#AssignmentsModule',
+                data: { preload: true }
             },
             {
                 path: 'mediafiles',
-                loadChildren: './mediafiles/mediafiles.module#MediafilesModule'
+                loadChildren: './mediafiles/mediafiles.module#MediafilesModule',
+                data: { preload: true }
             },
             {
                 path: 'motions',
-                loadChildren: './motions/motions.module#MotionsModule'
+                loadChildren: './motions/motions.module#MotionsModule',
+                data: { preload: true }
             },
             {
                 path: 'settings',
-                loadChildren: './config/config.module#ConfigModule'
+                loadChildren: './config/config.module#ConfigModule',
+                data: { preload: true }
             },
             {
                 path: 'users',
-                loadChildren: './users/users.module#UsersModule'
+                loadChildren: './users/users.module#UsersModule',
+                data: { preload: true }
             },
             {
                 path: 'tags',
-                loadChildren: './tags/tag.module#TagModule'
+                loadChildren: './tags/tag.module#TagModule',
+                data: { preload: true }
             },
             {
                 path: 'history',
-                loadChildren: './history/history.module#HistoryModule'
+                loadChildren: './history/history.module#HistoryModule',
+                data: { preload: true }
             },
             {
                 path: 'projectors',
-                loadChildren: './projector/projector.module#ProjectorModule'
+                loadChildren: './projector/projector.module#ProjectorModule',
+                data: { preload: true }
             }
         ],
         canActivateChild: [AuthGuard]