fix(frontend): preserve created feeds when preview loading fails

Gemfile

@@ -23,6 +23,7 @@ gem 'puma', require: false
 
 group :development do
   gem 'byebug'
+  gem 'irb', require: false
   gem 'rake', require: false
   gem 'rubocop', require: false
   gem 'rubocop-performance', require: false

frontend/src/__tests__/App.contract.test.tsx

@@ -30,7 +30,7 @@ describe('App contract', () => {
           })
         );
       }),
-      http.get('/api/v1/feeds/generated-token', ({ request }) => {
+      http.get('/api/v1/feeds/generated-token.json', ({ request }) => {
         expect(request.headers.get('accept')).toBe('application/feed+json');
 
         return HttpResponse.json(

frontend/src/__tests__/App.test.tsx

@@ -206,21 +206,22 @@ describe('App', () => {
   });
 
   it('renders the result panel when a feed is available', async () => {
-    vi.spyOn(window, 'fetch').mockResolvedValue({
-      ok: true,
-      json: async () => ({ items: [] }),
-    } as Response);
-
     mockUseFeedConversion.mockReturnValue({
       isConverting: false,
       result: {
-        id: 'feed-123',
-        name: 'Example Feed',
-        url: 'https://example.com/articles',
-        strategy: 'faraday',
-        feed_token: 'example-token',
-        public_url: '/api/v1/feeds/example-token',
-        json_public_url: '/api/v1/feeds/example-token.json',
+        feed: {
+          id: 'feed-123',
+          name: 'Example Feed',
+          url: 'https://example.com/articles',
+          strategy: 'faraday',
+          feed_token: 'example-token',
+          public_url: '/api/v1/feeds/example-token',
+          json_public_url: '/api/v1/feeds/example-token.json',
+        },
+        preview: {
+          items: [],
+          error: 'Preview unavailable right now.',
+        },
       },
       error: null,
       convertFeed: mockConvertFeed,
@@ -233,6 +234,7 @@ describe('App', () => {
     expect(screen.getByRole('button', { name: 'Create another feed' })).toBeInTheDocument();
     expect(screen.queryByRole('link', { name: 'Bookmarklet' })).not.toBeInTheDocument();
     expect(screen.getByText('Example Feed')).toBeInTheDocument();
+    expect(screen.getByText('Preview unavailable right now.')).toBeInTheDocument();
   });
 
   it('surfaces conversion errors to the user', () => {
@@ -250,6 +252,24 @@ describe('App', () => {
     expect(screen.getByText('Access denied')).toBeInTheDocument();
   });
 
+  it('shows an explicit loading notice while feed creation is still resolving preview state', () => {
+    mockUseFeedConversion.mockReturnValue({
+      isConverting: true,
+      result: null,
+      error: null,
+      convertFeed: mockConvertFeed,
+      clearError: mockClearConversionError,
+      clearResult: mockClearResult,
+    });
+
+    render(<App />);
+
+    expect(screen.getByText('Preparing feed')).toBeInTheDocument();
+    expect(
+      screen.getByText('Creating the feed and loading its preview before showing the result.')
+    ).toBeInTheDocument();
+  });
+
   it('clears stored token from instance info', () => {
     mockUseAccessToken.mockReturnValue({
       token: 'saved-token',

frontend/src/__tests__/ResultDisplay.test.tsx

@@ -6,39 +6,41 @@ import { ResultDisplay } from '../components/ResultDisplay';
 describe('ResultDisplay', () => {
   const mockOnCreateAnother = vi.fn();
   const mockResult = {
-    id: 'test-id',
-    name: 'Test Feed',
-    url: 'https://example.com',
-    strategy: 'faraday',
-    feed_token: 'test-feed-token',
-    public_url: 'https://example.com/feed.xml',
-    json_public_url: 'https://example.com/feed.json',
+    feed: {
+      id: 'test-id',
+      name: 'Test Feed',
+      url: 'https://example.com',
+      strategy: 'faraday',
+      feed_token: 'test-feed-token',
+      public_url: 'https://example.com/feed.xml',
+      json_public_url: 'https://example.com/feed.json',
+    },
+    preview: {
+      items: [
+        {
+          title: 'Item One',
+          excerpt: 'First preview item with markup.',
+          url: 'https://example.com/item-one',
+          publishedLabel: 'Jan 1, 2024',
+        },
+        {
+          title: '56 points by canpan 1 hour ago | hide | 18 comments',
+          excerpt: '',
+          publishedLabel: 'Jan 2, 2024',
+        },
+        {
+          title: 'Item Two',
+          excerpt: '',
+          url: 'https://example.com/item-two',
+          publishedLabel: 'Jan 3, 2024',
+        },
+      ],
+      error: null,
+    },
   };
 
   beforeEach(() => {
     vi.clearAllMocks();
-    vi.spyOn(window, 'fetch').mockResolvedValue({
-      ok: true,
-      json: async () => ({
-        items: [
-          {
-            title: 'Item One',
-            content_text: '<p>First preview item with <strong>markup</strong>.</p>',
-            url: 'https://example.com/item-one',
-            date_published: '2024-01-01T00:00:00Z',
-          },
-          {
-            content_text: '56 points by canpan 1 hour ago | hide | 18&nbsp;comments',
-            date_published: '2024-01-02T00:00:00Z',
-          },
-          {
-            content_text: '2. Item Two ( example.com )',
-            url: 'https://example.com/item-two',
-            date_published: '2024-01-03T00:00:00Z',
-          },
-        ],
-      }),
-    } as Response);
   });
 
   it('renders the success state actions and richer preview cards', async () => {
@@ -60,18 +62,15 @@ describe('ResultDisplay', () => {
       expect(screen.getByText('Item Two')).toBeInTheDocument();
       expect(screen.getByText('Latest items from this feed')).toBeInTheDocument();
     });
-    expect(window.fetch).toHaveBeenCalledWith('https://example.com/feed.xml', {
-      headers: { Accept: 'application/feed+json' },
-    });
   });
 
-  it('surfaces preview fetch failures as a result-state message', async () => {
-    vi.mocked(window.fetch).mockResolvedValueOnce({
-      ok: false,
-      json: async () => ({}),
-    } as Response);
-
-    render(<ResultDisplay result={mockResult} onCreateAnother={mockOnCreateAnother} />);
+  it('surfaces preview failures as a result-state message', async () => {
+    render(
+      <ResultDisplay
+        result={{ ...mockResult, preview: { items: [], error: 'Preview unavailable right now.' } }}
+        onCreateAnother={mockOnCreateAnother}
+      />
+    );
 
     await waitFor(() => {
       expect(screen.getByText('Preview unavailable right now.')).toBeInTheDocument();

frontend/src/__tests__/setup.ts

@@ -1,7 +1,8 @@
 import '@testing-library/jest-dom';
 import { afterAll, afterEach, beforeAll, beforeEach, vi } from 'vitest';
 import { cleanup } from '@testing-library/preact';
-import { server } from './mocks/server';
+
+let server: typeof import('./mocks/server').server;
 
 // Mock window and document for tests
 Object.defineProperty(window, 'matchMedia', {
@@ -49,10 +50,16 @@ const session = createStorageMock();
 Object.defineProperty(window, 'localStorage', {
   value: local.api,
 });
+Object.defineProperty(globalThis, 'localStorage', {
+  value: local.api,
+});
 
 Object.defineProperty(window, 'sessionStorage', {
   value: session.api,
 });
+Object.defineProperty(globalThis, 'sessionStorage', {
+  value: session.api,
+});
 
 beforeEach(() => {
   local.store.clear();
@@ -80,7 +87,10 @@ Object.assign(navigator, {
 Element.prototype.scrollIntoView = vi.fn();
 
 // Wire up MSW in node environment
-beforeAll(() => server.listen({ onUnhandledRequest: 'error' }));
+beforeAll(async () => {
+  ({ server } = await import('./mocks/server'));
+  server.listen({ onUnhandledRequest: 'error' });
+});
 afterEach(() => {
   server.resetHandlers();
   cleanup();

frontend/src/__tests__/useFeedConversion.contract.test.ts

@@ -24,6 +24,20 @@ describe('useFeedConversion contract', () => {
           }),
           { status: 201 }
         );
+      }),
+      http.get('/api/v1/feeds/generated-token.json', ({ request }) => {
+        expect(request.headers.get('accept')).toBe('application/feed+json');
+
+        return HttpResponse.json({
+          items: [
+            {
+              title: 'Generated item',
+              content_text: 'Contract preview',
+              url: 'https://example.com/items/generated',
+              date_published: '2024-01-02T00:00:00Z',
+            },
+          ],
+        });
       })
     );
 
@@ -35,9 +49,11 @@ describe('useFeedConversion contract', () => {
 
     expect(receivedAuthorization).toBe('Bearer test-token-123');
     expect(result.current.error).toBeNull();
-    expect(result.current.result?.feed_token).toBe('generated-token');
-    expect(result.current.result?.public_url).toBe('/api/v1/feeds/generated-token');
-    expect(result.current.result?.json_public_url).toBe('/api/v1/feeds/generated-token.json');
+    expect(result.current.result?.feed.feed_token).toBe('generated-token');
+    expect(result.current.result?.feed.public_url).toBe('/api/v1/feeds/generated-token');
+    expect(result.current.result?.feed.json_public_url).toBe('/api/v1/feeds/generated-token.json');
+    expect(result.current.result?.preview.error).toBeNull();
+    expect(result.current.result?.preview.items).toHaveLength(1);
   });
 
   it('propagates API validation errors', async () => {
@@ -83,4 +99,31 @@ describe('useFeedConversion contract', () => {
     expect(result.current.result).toBeNull();
     expect(result.current.error).toBe('Invalid response format from feed creation API');
   });
+
+  it('preserves the created feed when preview loading fails', async () => {
+    server.use(
+      http.post('/api/v1/feeds', async () =>
+        HttpResponse.json(
+          buildFeedResponse({
+            feed_token: 'generated-token',
+            public_url: '/api/v1/feeds/generated-token',
+            json_public_url: '/api/v1/feeds/generated-token.json',
+          }),
+          { status: 201 }
+        )
+      ),
+      http.get('/api/v1/feeds/generated-token.json', async () => new HttpResponse(null, { status: 502 }))
+    );
+
+    const { result } = renderHook(() => useFeedConversion());
+
+    await act(async () => {
+      await result.current.convertFeed('https://example.com/articles', 'faraday', 'token');
+    });
+
+    expect(result.current.error).toBeNull();
+    expect(result.current.result?.feed.feed_token).toBe('generated-token');
+    expect(result.current.result?.preview.items).toEqual([]);
+    expect(result.current.result?.preview.error).toBe('Preview unavailable right now.');
+  });
 });