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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;
},
};