Web Application Testing

To test local web applications, write native Python Playwright scripts.

Helper Scripts Available:

• scripts/with_server.py – Manages server lifecycle (supports multiple servers)

Always run scripts with --help first to see usage. DO NOT read the source until you try running the script first and find that a customized solution is abslutely necessary. These scripts can be very large and thus pollute your context window. They exist to be called directly as black-box scripts rather than ingested into your context window.

Decision Tree: Choosing Your Approach

User task → Is it static HTML?
    ├─ Yes → Read HTML file directly to identify selectors
    │         ├─ Success → Write Playwright script using selectors
    │         └─ Fails/Incomplete → Treat as dynamic (below)
    │
    └─ No (dynamic webapp) → Is the server already running?
        ├─ No → Run: python scripts/with_server.py --help
        │        Then use the helper + write simplified Playwright script
        │
        └─ Yes → Reconnaissance-then-action:
            1. Navigate and wait for networkidle
            2. Take screenshot or inspect DOM
            3. Identify selectors from rendered state
            4. Execute actions with discovered selectors

Example: Using with_server.py

To start a server, run --help first, then use the helper:

Single server:

python scripts/with_server.py --server "npm run dev" --port 5173 -- python your_automation.py

Multiple servers (e.g., backend + frontend):

python scripts/with_server.py \
  --server "cd backend && python server.py" --port 3000 \
  --server "cd frontend && npm run dev" --port 5173 \
  -- python your_automation.py

To create an automation script, include only Playwright logic (servers are managed automatically):

from playwright.sync_api import sync_playwright

with sync_playwright() as p:
    browser = p.chromium.launch(headless=True) # Always launch chromium in headless mode
    page = browser.new_page()
    page.goto('http://localhost:5173') # Server already running and ready
    page.wait_for_load_state('networkidle') # CRITICAL: Wait for JS to execute
    # ... your automation logic
    browser.close()

Reconnaissance-Then-Action Pattern

1. Inspect rendered DOM:

   page.screenshot(path='/tmp/inspect.png', full_page=True)
   content = page.content()
   page.locator('button').all()
   

2. Identify selectors from inspection results

3. Execute actions using discovered selectors

Common Pitfall

❌ Don’t inspect the DOM before waiting for networkidle on dynamic apps ✅ Do wait for page.wait_for_load_state('networkidle') before inspection

🔄 Workflow

Kaynak: Playwright Python Documentation & Testing Hybrid Web Apps (2025)

Aşama 1: Environment & Reconnaissance

• Server Management: scripts/with_server.py --server "..." kullanarak test ortamını (Frontend/Backend) otomatik ayağa kaldır.
• DOM Inspection: networkidle state’ine ulaştıktan sonra page.content() ve screenshot ile selector analizi yap.
• Selector Strategy: Kararlı testler için role, text veya test-id bazlı selector’ları belirle.

Aşama 2: Scripting & Automation

• Action Chain: Playwright API kullanarak tıklama, form doldurma ve navigasyon adımlarını kodla.
• Assertion Logic: expect() metodlarıyla sayfa başlığı, element görünürlüğü veya URL doğruluğunu kontrol et.
• Visual Testing: Arayüz tutarlılığı için Snapshot karşılaştırmaları (screenshot audit) yap.

Aşama 3: Debug & Reporting

• Log Audit: Tarayıcı konsol çıktılarını (Console logs) ve ağ hatalarını (Failed requests) incele.
• Trace Analysis: Başarısız testler için Playwright Trace Viewer kullanarak adım adım hata ayıklama yap.
• CI/CD Alignment: Testlerin headless modda ve sürekli entegrasyon hattında sorunsuz çalıştığını doğrula.

Kontrol Noktaları

Webapp Testing v2.0 – With Workflow