feat: SSE client + hello page + CSS palette + component test (#22, #23)

frontend/src/App.css

@@ -1,182 +1,59 @@
-.counter {
-  font-size: 16px;
-  padding: 5px 10px;
-  border-radius: 5px;
-  color: var(--accent);
-  background: var(--accent-bg);
-  border: 2px solid transparent;
-  transition: border-color 0.3s;
-  margin-bottom: 24px;
-
-  &:hover {
-    border-color: var(--accent-border);
-  }
-  &:focus-visible {
-    outline: 2px solid var(--accent);
-    outline-offset: 2px;
-  }
+.app {
+  max-width: 56rem;
+  margin: 0 auto;
+  padding: var(--space-2xl) var(--space-xl);
 }
 
-.hero {
-  position: relative;
-
-  .base,
-  .framework,
-  .vite {
-    inset-inline: 0;
-    margin: 0 auto;
-  }
-
-  .base {
-    width: 170px;
-    position: relative;
-    z-index: 0;
-  }
-
-  .framework,
-  .vite {
-    position: absolute;
-  }
-
-  .framework {
-    z-index: 1;
-    top: 34px;
-    height: 28px;
-    transform: perspective(2000px) rotateZ(300deg) rotateX(44deg) rotateY(39deg) scale(1.4);
-  }
-
-  .vite {
-    z-index: 0;
-    top: 107px;
-    height: 26px;
-    width: auto;
-    transform: perspective(2000px) rotateZ(300deg) rotateX(40deg) rotateY(39deg) scale(0.8);
-  }
+.app h1 {
+  margin: 0 0 var(--space-sm);
+  color: var(--text-primary);
 }
 
-#center {
-  display: flex;
-  flex-direction: column;
-  gap: 25px;
-  place-content: center;
-  place-items: center;
-  flex-grow: 1;
-
-  @media (max-width: 1024px) {
-    padding: 32px 20px 24px;
-    gap: 18px;
-  }
+.app .subtitle {
+  margin: 0 0 var(--space-2xl);
+  color: var(--text-secondary);
 }
 
-#next-steps {
-  display: flex;
-  border-top: 1px solid var(--border);
-  text-align: left;
-
-  & > div {
-    flex: 1 1 0;
-    padding: 32px;
-    @media (max-width: 1024px) {
-      padding: 24px 20px;
-    }
-  }
-
-  .icon {
-    margin-bottom: 16px;
-    width: 22px;
-    height: 22px;
-  }
-
-  @media (max-width: 1024px) {
-    flex-direction: column;
-    text-align: center;
-  }
+.health {
+  border: 1px solid var(--border-default);
+  border-radius: var(--radius-md);
+  padding: var(--space-lg) var(--space-xl);
+  background: var(--bg-secondary);
 }
 
-#docs {
-  border-right: 1px solid var(--border);
-
-  @media (max-width: 1024px) {
-    border-right: none;
-    border-bottom: 1px solid var(--border);
-  }
+.health h2 {
+  margin: 0 0 var(--space-md);
+  font-size: 1.05rem;
+  color: var(--text-secondary);
 }
 
-#next-steps ul {
-  list-style: none;
-  padding: 0;
-  display: flex;
-  gap: 8px;
-  margin: 32px 0 0;
-
-  .logo {
-    height: 18px;
-  }
-
-  a {
-    color: var(--text-h);
-    font-size: 16px;
-    border-radius: 6px;
-    background: var(--social-bg);
-    display: flex;
-    padding: 6px 12px;
-    align-items: center;
-    gap: 8px;
-    text-decoration: none;
-    transition: box-shadow 0.3s;
-
-    &:hover {
-      box-shadow: var(--shadow);
-    }
-    .button-icon {
-      height: 18px;
-      width: 18px;
-    }
-  }
-
-  @media (max-width: 1024px) {
-    margin-top: 20px;
-    flex-wrap: wrap;
-    justify-content: center;
-
-    li {
-      flex: 1 1 calc(50% - 8px);
-    }
-
-    a {
-      width: 100%;
-      justify-content: center;
-      box-sizing: border-box;
-    }
-  }
+.health p {
+  margin: 0;
 }
 
-#spacer {
-  height: 88px;
-  border-top: 1px solid var(--border);
-  @media (max-width: 1024px) {
-    height: 48px;
-  }
+.badge {
+  display: inline-block;
+  padding: var(--space-xs) var(--space-md);
+  border-radius: var(--radius-sm);
+  font-size: 0.85rem;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.04em;
 }
 
-.ticks {
-  position: relative;
-  width: 100%;
+.badge--ok {
+  background: var(--accent-success);
+  color: var(--bg-primary);
+}
 
-  &::before,
-  &::after {
-    content: '';
-    position: absolute;
-    top: -4.5px;
-    border: 5px solid transparent;
-  }
+.badge--error {
+  background: var(--accent-error);
+  color: var(--bg-primary);
+}
 
-  &::before {
-    left: 0;
-    border-left-color: var(--border);
-  }
-  &::after {
-    right: 0;
-    border-right-color: var(--border);
-  }
+code {
+  background: var(--bg-tertiary);
+  padding: 0 var(--space-xs);
+  border-radius: var(--radius-sm);
+  font-size: 0.95em;
 }

frontend/src/App.test.tsx

@@ -0,0 +1,49 @@
+import { describe, expect, it, beforeEach, afterEach, vi } from 'vitest'
+import { render, screen, waitFor } from '@testing-library/react'
+import App from './App'
+
+describe('App health probe', () => {
+  beforeEach(() => {
+    vi.restoreAllMocks()
+  })
+  afterEach(() => {
+    vi.restoreAllMocks()
+  })
+
+  it('renders the loading state, then the health badge once /api/v1/health resolves', async () => {
+    const fetchSpy = vi.spyOn(globalThis, 'fetch').mockResolvedValueOnce({
+      ok: true,
+      status: 200,
+      json: async () => ({ status: 'ok', version: '0.1.0' }),
+    } as Response)
+
+    render(<App />)
+
+    expect(screen.getByRole('status')).toHaveTextContent(/Checking/i)
+
+    await waitFor(() => {
+      expect(screen.getByTestId('health-ok')).toBeInTheDocument()
+    })
+    expect(screen.getByTestId('health-ok')).toHaveTextContent(/ok/i)
+    expect(screen.getByTestId('health-ok')).toHaveTextContent(/v0\.1\.0/)
+    expect(fetchSpy).toHaveBeenCalledWith(
+      '/api/v1/health',
+      expect.objectContaining({ signal: expect.any(AbortSignal) })
+    )
+  })
+
+  it('renders the error state when /api/v1/health 500s', async () => {
+    vi.spyOn(globalThis, 'fetch').mockResolvedValueOnce({
+      ok: false,
+      status: 500,
+      json: async () => ({}),
+    } as Response)
+
+    render(<App />)
+
+    await waitFor(() => {
+      expect(screen.getByTestId('health-error')).toBeInTheDocument()
+    })
+    expect(screen.getByTestId('health-error')).toHaveTextContent(/HTTP 500/)
+  })
+})