How does Chrome browser solve cross-origin issues?

Chrome Cross-Origin Problem Solutions

Cross-origin issues are common in web development, and Chrome browser provides multiple solutions.

Causes of Cross-Origin Issues

Browser's same-origin policy restricts resource access between different origins. Origin is determined by protocol, domain, and port.

Solutions

1. CORS (Cross-Origin Resource Sharing)

   • Server sets Access-Control-Allow-Origin header
   • Supports simple requests and preflight requests
   • Can specify allowed HTTP methods and headers

2. JSONP (JSON with Padding)

   • Uses script tag which is not restricted by same-origin policy
   • Only supports GET requests
   • Requires server cooperation

3. Proxy Server

   • Use same-origin server as proxy
   • Proxy server forwards requests to target server
   • Commonly used webpack devServer proxy in development

4. PostMessage

   • Used for communication between different windows
   • Supports cross-origin iframe communication
   • Need to explicitly specify message source

5. WebSocket

   • WebSocket is not restricted by same-origin policy
   • Suitable for real-time communication scenarios
   • Requires server support

Development Environment Configuration

• Add --disable-web-security parameter when starting Chrome (development only)
• Use CORS plugin (development only)
• Configure webpack devServer proxy

Best Practices

• Use CORS in production
• Sensitive operations require additional security verification
• Avoid using JSONP, has security risks
• Set CORS headers appropriately, avoid over-opening