Web Application Testing

Write native Python Playwright scripts to test local webapps.

Helper: scripts/with_server.py manages server lifecycle. Run with --help first.

Approach

Static HTML: Read file → identify selectors → write script

Dynamic webapp:

• Server not running: Use with_server.py
• Server running: Navigate → wait networkidle → inspect → act

Server Management

# Single server
python scripts/with_server.py --server "npm run dev" --port 5173 -- python automation.py

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

Script Patterns

Automation:

from playwright.sync_api import sync_playwright

with sync_playwright() as p:
    browser = p.chromium.launch(headless=True)
    page = browser.new_page()
    page.goto('http://localhost:5173')
    page.wait_for_load_state('networkidle') # CRITICAL for dynamic apps
    # automation logic here
    browser.close()

Reconnaissance:

page.screenshot(path='/tmp/inspect.png', full_page=True)
page.content() # Get HTML
page.locator('button').all() # Find elements

Critical Rules

• Always page.wait_for_load_state('networkidle') before DOM inspection
• Use descriptive selectors: text=, role=, CSS, IDs
• Close browser when done
• See examples/ for more patterns