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Define CORS headers

Adjust Cross-Origin Resource Sharing (CORS) headers and handle preflight requests.

// Define CORS headers
const corsHeaders = {
  "Access-Control-Allow-Origin": "*", // Replace * with your allowed origin(s)
  "Access-Control-Allow-Methods": "GET, POST, PUT, DELETE, OPTIONS", // Adjust allowed methods as needed
  "Access-Control-Allow-Headers": "Content-Type, Authorization", // Adjust allowed headers as needed
  "Access-Control-Max-Age": "86400", // Adjust max age (in seconds) as needed
};


export default {
  async fetch(request) {
    // Make a copy of the request to modify its headers
    const modifiedRequest = new Request(request);


    // Handle preflight requests (OPTIONS)
    if (request.method === "OPTIONS") {
      return new Response(null, {
        headers: {
          ...corsHeaders,
        },
        status: 200, // Respond with OK status for preflight requests
      });
    }


    // Pass the modified request through to the origin
    const response = await fetch(modifiedRequest);


    // Make a copy of the response to modify its headers
    const modifiedResponse = new Response(response.body, response);


    // Set CORS headers on the response
    Object.keys(corsHeaders).forEach((header) => {
      modifiedResponse.headers.set(header, corsHeaders[header]);
    });


    return modifiedResponse;
  },
};
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