How do I analyze HTTP requests for web scraping?

Analyzing HTTP requests is crucial for successful web scraping because you need to replicate how real browsers communicate with servers.

Step-by-step process:

1. Open browser DevTools (F12)
2. Navigate to the Network tab
3. Perform the action you want to scrape (load a page, submit a form, etc.)
4. Click on the relevant request to view detailed information

What to examine:

• Request headers
• Response headers
• Cookies
• Request payload (for POST requests)
• Response body

Pay special attention to:

Required headers that many sites need:

• User-Agent
• Accept
• Accept-Language
• Referer

Authentication headers:

• Authorization
• X-API-Key
• Custom authentication tokens

Handling dynamic content:

For AJAX-heavy sites, identify XHR or Fetch requests that load data dynamically:

• These often return JSON data that's easier to parse than HTML
• Look for API endpoints that return structured data
• Check request payloads for parameters that control data fetching

Cookies and CSRF tokens:

Check if requests include:

• Cookies that must be obtained from previous requests
• CSRF tokens embedded in forms or headers
• Session IDs that need to be maintained

Export and convert:

Use the "Copy as cURL" feature to export the request, then convert it to your programming language using a cURL converter.

Using our tool:

Our HTTP Request Analyzer shows you what headers your current browser sends, which you can use as a reference for your scraper.

Common mistakes:

• Missing the Referer header (which some sites require)
• Sending requests too fast (triggering rate limiting)
• Failing to handle cookies across multiple requests
• Not maintaining session state
• Using default library user agents