special ifExperimental directive to toggle features (#445)

src/app.config.json

@@ -8,6 +8,7 @@
         "copyright":
             "© 2017 - 2018 Alfresco Software, Inc. All rights reserved."
     },
+    "experimental": {},
     "headerColor": "#2196F3",
     "languagePicker": false,
     "pagination": {

src/app/app.module.ts

@@ -79,6 +79,7 @@ import { AppStoreModule } from './store/app-store.module';
 import { PaginationDirective } from './directives/pagination.directive';
 import { DocumentListDirective } from './directives/document-list.directive';
 import { MaterialModule } from './material.module';
+import { ExperimentalDirective } from './directives/experimental.directive';
 
 @NgModule({
     imports: [
@@ -132,7 +133,8 @@ import { MaterialModule } from './material.module';
         CreateFolderDirective,
         DownloadNodesDirective,
         PaginationDirective,
-        DocumentListDirective
+        DocumentListDirective,
+        ExperimentalDirective
     ],
     providers: [
         { provide: PageTitleService, useClass: AcaPageTitleService },

src/app/directives/experimental.directive.ts

@@ -0,0 +1,52 @@
+/*!
+ * @license
+ * Alfresco Example Content Application
+ *
+ * Copyright (C) 2005 - 2018 Alfresco Software Limited
+ *
+ * This file is part of the Alfresco Example Content Application.
+ * If the software was purchased under a paid Alfresco license, the terms of
+ * the paid license agreement will prevail.  Otherwise, the software is
+ * provided under the following open source license terms:
+ *
+ * The Alfresco Example Content Application is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The Alfresco Example Content Application is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import { Directive, TemplateRef, ViewContainerRef, Input } from '@angular/core';
+import { AppConfigService } from '@alfresco/adf-core';
+import { environment } from '../../environments/environment';
+
+@Directive({
+    // tslint:disable-next-line:directive-selector
+    selector: '[ifExperimental]'
+})
+export class ExperimentalDirective {
+    constructor(
+        private templateRef: TemplateRef<any>,
+        private viewContainerRef: ViewContainerRef,
+        private config: AppConfigService
+    ) {}
+
+    @Input() set ifExperimental(featureKey: string) {
+        if (!environment.production) {
+            const value = this.config.get<boolean>(`experimental.${featureKey}`);
+            if (value) {
+                this.viewContainerRef.createEmbeddedView(this.templateRef);
+                return;
+            }
+        }
+
+        this.viewContainerRef.clear();
+    }
+}