api form directive

src/app/directives/api-form.directive.ts

@@ -0,0 +1,32 @@
+import {
+    Directive,
+    ElementRef,
+    Input,
+    OnChanges,
+} from '@angular/core';
+
+import { ValidationService } from '../services/validation.service';
+
+@Directive({
+    selector: '[appApiForm]',
+})
+export class ApiFormDirective implements OnChanges {
+    @Input() appApiForm: Promise<any>;
+
+    constructor(private el: ElementRef, private validationService: ValidationService) { }
+
+    ngOnChanges(changes: any) {
+        if (this.appApiForm == null || this.appApiForm.then == null) {
+            return;
+        }
+
+        this.el.nativeElement.loading = true;
+
+        this.appApiForm.then((response: any) => {
+            this.el.nativeElement.loading = false;
+        }, (e: any) => {
+            this.el.nativeElement.loading = false;
+            this.validationService.showError(e);
+        });
+    }
+}