Add withDelay middleware

example/msw.ts

@@ -1,5 +1,5 @@
 import { setupWorker } from 'msw/browser';
-import { MswServer } from '../src/FakeRest';
+import { MswServer, withDelay } from '../src/FakeRest';
 import { data } from './data';
 import { HttpResponse } from 'msw';
 
@@ -8,17 +8,18 @@ const restServer = new MswServer({
     data,
 });
 
+restServer.addMiddleware(withDelay(5000));
 restServer.addMiddleware(async (request, context, next) => {
     if (!request.headers?.get('Authorization')) {
-        return new HttpResponse(null, { status: 401 });
+        throw new HttpResponse(null, { status: 401 });
     }
 
     if (
         context.collection === 'books' &&
         request.method === 'POST' &&
         !context.requestJson?.title
     ) {
-        return new HttpResponse(null, {
+        throw new HttpResponse(null, {
             status: 400,
             statusText: 'Title is required',
         });

src/FakeRest.ts

@@ -7,6 +7,7 @@ import {
 import { Collection } from './Collection.js';
 import { Single } from './Single.js';
 import { getMswHandlers, MswServer } from './msw.js';
+import { withDelay } from './withDelay.js';
 
 export {
     getSinonHandler,
@@ -19,6 +20,7 @@ export {
     MswServer,
     Collection,
     Single,
+    withDelay,
 };
 
 export default {
@@ -32,4 +34,5 @@ export default {
     MswServer,
     Collection,
     Single,
+    withDelay,
 };

src/withDelay.ts

@@ -0,0 +1,11 @@
+import type { Middleware } from './BaseServerWithMiddlewares.js';
+
+export const withDelay =
+    <RequestType>(delayMs: number): Middleware<RequestType> =>
+    (request, context, next) => {
+        return new Promise((resolve) => {
+            setTimeout(() => {
+                resolve(next(request, context));
+            }, delayMs);
+        });
+    };