add documentation for cache api on deploy

deploy/manual/edge-cache.md

@@ -0,0 +1,37 @@
+# Edge Cache
+
+:::caution Beta feature
+
+Cache API support on Deno Deploy is currently in beta.
+
+:::
+
+The [Web Cache API](https://developer.mozilla.org/en-US/docs/Web/API/Cache) is
+supported on Deno Deploy. The cache is designed to provide microsecond-level
+read latency, multi-GB/s write throughput and unbounded storage, with the
+tradeoff of best-effort consistency and durability.
+
+```ts
+const cache = await caches.open("my-cache");
+
+Deno.serve(async (req) => {
+ const cached = await cache.match(req);
+ if (cached) {
+ return cached;
+ }
+
+ const res = new Response("cached at " + new Date().toISOString());
+ await cache.put(req, res.clone());
+ return res;
+});
+```
+
+Cached data is stored in the same Deno Deploy region that runs your code.
+Usually your isolate observes read-after-write (RAW) and write-after-write (WAW)
+consistency within the same region; however, in rare cases recent writes can be
+lost, out-of-order or temporarily invisible.
+
+## Limitations
+
+- The `Content-Length` header is required for cached requests.
+- Deletion is not yet supported.

sidebars/deploy.js

@@ -84,6 +84,11 @@ const sidebars = {
  "kv/manual/cron",
  ],
  },
+ {
+ type: "doc",
+ id: "manual/edge-cache",
+ label: "Edge Cache",
+ },
  {
  type: "html",
  value: "<div>Connecting to Databases</div>",