Kanna is a Swift library for parsing HTML and XML documents. It is primarily used in iOS and macOS development to extract data from webpages or XML documents. Unfortunately, Kanna by itself does not have the capability to handle JavaScript or AJAX-loaded content, as it does not include a JavaScript engine to execute scripts or dynamically load content after the initial page load.
To scrape AJAX-loaded content, you would need to use a tool or library that can run a browser engine or simulate it to allow for the execution of JavaScript and the loading of content dynamically. Here are a few approaches to scrape AJAX-loaded content:
1. Use a headless browser
You can use a headless browser such as Puppeteer (for Node.js), Selenium, or Playwright. These tools can control a browser programmatically, allowing you to render JavaScript and scrape the resulting DOM.
Example using Python with Selenium:
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
from webdriver_manager.chrome import ChromeDriverManager
# Initialize a headless Chrome browser
options = webdriver.ChromeOptions()
options.add_argument('--headless')
driver = webdriver.Chrome(service=Service(ChromeDriverManager().install()), options=options)
# Navigate to the page with AJAX content
driver.get('http://example.com/ajax-content')
# Wait for the content to load (could also use explicit waits)
driver.implicitly_wait(10)
# Now you can use Kanna or BeautifulSoup to parse the page source
html_content = driver.page_source
# Close the browser
driver.quit()
# Use the html_content with Kanna or BeautifulSoup
2. Use an HTTP client with JavaScript rendering
An HTTP client that can interpret and execute JavaScript such as Splash can be used to retrieve AJAX-loaded content.
Example using Python with requests to interact with Splash:
import requests
# Splash must be running as a service
splash_url = 'http://localhost:8050/render.html'
target_url = 'http://example.com/ajax-content'
# Make a request to Splash to process the JavaScript on the page
response = requests.get(splash_url, params={'url': target_url, 'wait': 2})
# The response will contain the HTML after JavaScript execution
html_content = response.text
# Use the html_content with Kanna or BeautifulSoup
3. Analyze network requests
Sometimes, you can analyze the network requests made by the webpage to load AJAX content and directly make those requests using an HTTP client to get the data without executing JavaScript.
Example using Python with requests:
import requests
# The URL for the AJAX request (found by analyzing network traffic)
ajax_url = 'http://example.com/ajax-endpoint'
# Make a request directly to the AJAX endpoint
response = requests.get(ajax_url)
# Process the JSON or HTML response
data = response.json() # or response.text if the response is HTML
Conclusion
While Kanna itself is not suitable for scraping AJAX-loaded content, you can use it in conjunction with other tools that provide JavaScript execution capabilities. The typical approach is to fetch the fully rendered HTML after JavaScript execution using a headless browser or similar tool and then parse it using Kanna or another parsing library.
