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Using the Cache API

Use the Cache API to store responses in Cloudflare's cache.

async function handleRequest(event) {
const request = event.request
const cacheUrl = new URL(request.url)
// Construct the cache key from the cache URL
const cacheKey = new Request(cacheUrl.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 origin, and store it in the cache
// for future access
let response = await cache.match(cacheKey)
if (!response) {
// If not in cache, get it from origin
response = await fetch(request)
// Must use Response constructor to inherit all of response's fields
response = new Response(response.body, response)
// 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
response.headers.append("Cache-Control", "s-maxage=10")
// Store the fetched response as cacheKey
// Use waitUntil so you can return the response without blocking on
// writing to cache
event.waitUntil(cache.put(cacheKey, response.clone()))
return response
addEventListener("fetch", event => {
try {
const request = event.request
return event.respondWith(handleRequest(event))
} catch (e) {
return event.respondWith(new Response("Error thrown " + e.message))