How to Wait for Page to Load in Playwright?

Best practices

Use wait_until='networkidle' in the page.goto() method to ensure all network requests have finished and all data has loaded before proceeding.
Set wait_until='domcontentloaded' to wait only for the HTML document to be fully loaded and parsed, which is faster when you don't need to wait for stylesheets, images, and subframes to finish loading.
Opt for wait_until='load' when you need to ensure that the whole page, including all dependent resources, is fully loaded.
Regularly update Playwright to leverage improvements and new features in handling page load strategies.

# pip install playwright
from playwright.sync_api import sync_playwright


url = 'https://sandbox.oxylabs.io/products'

with sync_playwright() as p:
    browser = p.chromium.launch()
    page = browser.new_page()

    # Navigate to the URL and wait until network is idle
    page.goto(url, wait_until='networkidle')
    print(page.title())

    # Alternative: wait until DOM is fully loaded
    page.goto(url, wait_until='domcontentloaded')
    print(page.title())

    # Another method: wait until everything is loaded
    page.goto(url, wait_until='load')
    print(page.title())
    
    browser.close()

Common issues

Ensure that your network conditions are stable and fast enough to avoid timeouts during page loads in Playwright.
If the page consistently takes longer to load, increase the default timeout in page.goto() to prevent premature termination.
Utilize page.wait_for_selector('your-selector') to wait for specific elements to appear on the page, ensuring that dynamic content is fully loaded.
Check for any JavaScript errors in the console after the page load that might indicate issues with complete page rendering.

# Incorrect: Using a very short timeout might lead to errors if the page takes longer to load
try:
    page.goto(url, timeout=10)
    print(page.title())
except:
    print('Timeout exceeded')

# Correct: Increasing the timeout to handle slow page loads
page.goto(url, timeout=10000)
print(page.title())


# Incorrect: Assuming page elements are available immediately after page.goto
page.goto(url)
# Might be None if the element loads dynamically
print(page.query_selector('.in-stock, .out-of-stock'))

# Correct: Waiting for a specific element to ensure it's loaded
page.goto(url)
page.wait_for_selector('.in-stock, .out-of-stock')
print(page.query_selector('.in-stock, .out-of-stock').text_content())


# Incorrect: Not checking for JavaScript errors which might affect page functionality
page.goto(url)

# Correct: Checking for JavaScript errors after loading the page
page.goto(url)
errors = page.evaluate('() => {return window.console.errors || [];}')
if errors:
    print('JavaScript errors found:', errors)


# Incorrect: Ignoring network conditions that might affect loading times
page.goto(url)
print(page.title())

# Correct: Adjusting settings based on network speed assumptions
slow_network = True
if slow_network:
    print('Slow network, adjusting settings.')
    page.set_extra_http_headers({'Cache-Control': 'no-cache'})
    page.goto(url, timeout=30000)
    print(page.title())
else:
    page.goto(url)
    print(page.title())