Edge Developer Platform
  • Edge Functions
    • Overview
    • Getting Started
    • Operation Guide
      • Function Management
      • Function Trigger
    • Runtime APIs
      • addEventListener
      • Cache
      • Cookies
      • Encoding
      • Fetch
      • FetchEvent
      • Headers
      • Request
      • Response
      • Streams
        • ReadableStream
        • ReadableStreamBYOBReader
        • ReadableStreamDefaultReader
        • TransformStream
        • WritableStream
        • WritableStreamDefaultWriter
      • Web Crypto
      • Web standards
      • Images
        • ImageProperties
    • Sample Functions
      • Returning an HTML Page
      • Returning a JSON Object
      • Fetch Remote Resources
      • Authenticating a Request Header
      • Modifying a Response Header
      • Performing an A/B Test
      • Setting Cookies
      • Performing Redirect Based on the Request Location
      • Using the Cache API
      • Caching POST Requests
      • Responding in Streaming Mode
      • Merging Resources and Responding in Streaming Mode
      • Protecting Data from Tampering
      • Rewriting a m3u8 File and Configuring Authentication
      • Adaptive Image Resize
      • Image Adaptive WebP
      • Customize Referer restriction rules
      • Remote Authentication
      • HMAC Digital Signature
      • Naming a Downloaded File
      • Obtaining Client IP Address
    • Best Practices
      • Adaptive Image Format Conversion via Edge Functions
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Sample Functions/
Authenticating a Request Header/

Authenticating a Request Header

This example demonstrates how to use an edge function to perform simple permission control by verifying the value of the x-custom-token request header. If the value is token-123456, access is allowed. Otherwise, access is denied.

Sample Code

async function handleRequest(request) {
  const token = request.headers.get('x-custom-token');

  if (token === 'token-123456') {
    return new Response('hello world');
  }

  // Incorrect key supplied. Reject the request.
  return new Response('Sorry, you have supplied an invalid token.', {
    status: 403,
  });
}

addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request));
});

Sample Preview

In the address bar of the browser, enter a URL that matches a trigger rule of the edge function to preview the effect of the sample code.
If authentication fails, access is denied.

If authentication is successful, access is allowed.


References

Runtime APIs: Headers
Runtime APIs: Response