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Use the Cache API

Use the Cache API to store R2 objects in Cloudflare’s cache.

export default {
async fetch(request, env, context) {
try {
const url = new URL(request.url);
// Construct the cache key from the cache URL
const cacheKey = new Request(url.toString(), request);
const cache = caches.default;
// Check whether the value is already available in the cache
// if not, you will need to fetch it from R2, and store it in the cache
// for future access
let response = await cache.match(cacheKey);
if (response) {
console.log(`Cache hit for: ${request.url}.`);
return response;
}
console.log(
`Response for request url: ${request.url} not present in cache. Fetching and caching request.`
);
// If not in cache, get it from R2
const objectKey = url.pathname.slice(1);
const object = await env.MY_BUCKET.get(objectKey);
if (object === null) {
return new Response('Object Not Found', { status: 404 });
}
// Set the appropriate object headers
const headers = new Headers();
object.writeHttpMetadata(headers);
headers.set('etag', object.httpEtag);
// Cache API respects Cache-Control headers. Setting s-max-age to 10
// will limit the response to be in cache for 10 seconds max
// Any changes made to the response here will be reflected in the cached value
headers.append('Cache-Control', 's-maxage=10');
response = new Response(object.body, {
headers,
});
// Store the fetched response as cacheKey
// Use waitUntil so you can return the response without blocking on
// writing to cache
context.waitUntil(cache.put(cacheKey, response.clone()));
return response;
} catch (e) {
return new Response('Error thrown ' + e.message);
}
},
};