Set the HTTP status code to 404 when a page is not found

The browser was getting 200.

Fixes https://github.com/DSpace/dspace-angular/issues/91

src/app/pagenotfound/pagenotfound.component.ts

@@ -1,12 +1,17 @@
-import { Component } from '@angular/core';
+import { ServerResponseService } from '../shared/server-response.service';
+import { Component, ChangeDetectionStrategy } from '@angular/core';
 
 @Component({
   selector: 'ds-pagenotfound',
   styleUrls: ['./pagenotfound.component.scss'],
-  templateUrl: './pagenotfound.component.html'
+  templateUrl: './pagenotfound.component.html',
+  providers: [ServerResponseService],
+  changeDetection: ChangeDetectionStrategy.OnPush
 })
 export class PageNotFoundComponent {
 
   data: any = {};
-
+  constructor(responseService: ServerResponseService) {
+    responseService.setNotFound();
+  }
 }

src/app/shared/server-response.service.ts

@@ -0,0 +1,26 @@
+import { RESPONSE } from '@nguniversal/express-engine/tokens';
+import { Inject, Injectable, Optional } from '@angular/core';
+import { Response } from 'express';
+
+@Injectable()
+export class ServerResponseService {
+  private response: Response;
+
+  constructor(@Optional() @Inject(RESPONSE) response: any) {
+    this.response = response;
+  }
+
+  setStatus(code: number, message?: string): this {
+    if (this.response) {
+      this.response.statusCode = code;
+      if (message) {
+        this.response.statusMessage = message;
+      }
+    }
+    return this;
+  }
+
+  setNotFound(message = 'Not found'): this {
+    return this.setStatus(404, message)
+  }
+}