use R2 CRUD example

Signed-off-by: Jason Hall <jason@chainguard.dev>

cf-worker/script.js

@@ -1,16 +1,38 @@
+// https://developers.cloudflare.com/r2/api/workers/workers-api-usage/#4-access-your-r2-bucket-from-your-worker
 export default {
-    async fetch(request, env, ctx) {
-        let value = await env.KV.get("foo");
-        await env.KV.put("foo", value + "r");
+    async fetch(request, env) {
+        const url = new URL(request.url);
+        const key = url.pathname.slice(1);
 
-        let obj = await env.R2.get("foo");
-        if (!obj) {
-            obj = "ba";
-        } else {
-            obj = await obj.text();
+        switch (request.method) {
+            case 'PUT':
+                await env.R2.put(key, request.body);
+                return new Response(`Put ${key} successfully!`);
+            case 'GET':
+                const object = await env.R2.get(key);
+
+                if (object === null) {
+                    return new Response('Object Not Found', { status: 404 });
+                }
+
+                const headers = new Headers();
+                object.writeHttpMetadata(headers);
+                headers.set('etag', object.httpEtag);
+
+                return new Response(object.body, {
+                    headers,
+                });
+            case 'DELETE':
+                await env.R2.delete(key);
+                return new Response('Deleted!');
+
+            default:
+                return new Response('Method Not Allowed', {
+                    status: 405,
+                    headers: {
+                        Allow: 'PUT, GET, DELETE',
+                    },
+                });
         }
-        await env.R2.put("foo", obj + "r");
-
-        return new Response(`${value} / ${obj}`);
     },
 };