chore(cloudflare): optimize Cache usage; strict TS source (#4453)

* chore(cloudflare): optimize Cache usage; strict TS source

* chore: add changeset

* skip lib check for conflicts

* bundle worktop (#4473)

* bundle worktop

* build on prepublishOnly

* Update packages/adapter-cloudflare/tsconfig.json

* update builder file paths

Co-authored-by: Luke Edwards <[email protected]>

* convert to JS (#4474)

* Update .changeset/empty-falcons-run.md

Co-authored-by: Rich Harris <[email protected]>

.changeset/empty-falcons-run.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/adapter-cloudflare': patch
+---
+
+Check for Cache match sooner; use `worktop` for types & Cache operations

packages/adapter-cloudflare/.gitignore

@@ -1,3 +1 @@
-.DS_Store
-node_modules
-target
+/files

packages/adapter-cloudflare/package.json

@@ -23,13 +23,16 @@
 	],
 	"main": "index.js",
 	"scripts": {
+		"build": "esbuild src/worker.js --bundle --outfile=files/worker.js --external:SERVER --external:MANIFEST --format=esm",
 		"lint": "eslint --ignore-path .gitignore \"**/*.{ts,js,svelte}\" && npm run check-format",
 		"format": "npm run check-format -- --write",
-		"check": "tsc",
-		"check-format": "prettier --check . --config ../../.prettierrc --ignore-path .gitignore"
+		"check": "tsc --skipLibCheck",
+		"check-format": "prettier --check . --config ../../.prettierrc --ignore-path .gitignore",
+		"prepublishOnly": "npm run build"
 	},
 	"dependencies": {
-		"esbuild": "^0.14.21"
+		"esbuild": "^0.14.21",
+		"worktop": "0.8.0-next.12"
 	},
 	"devDependencies": {
 		"@types/ws": "^8.5.3",

packages/adapter-cloudflare/src/worker.js

@@ -0,0 +1,68 @@
+import { Server } from 'SERVER';
+import { manifest, prerendered } from 'MANIFEST';
+import * as Cache from 'worktop/cfw.cache';
+
+const server = new Server(manifest);
+
+const prefix = `/${manifest.appDir}/`;
+
+/** @type {import('worktop/cfw').Module.Worker<{ ASSETS: import('worktop/cfw.durable').Durable.Object }>} */
+const worker = {
+	async fetch(req, env, context) {
+		try {
+			let res = await Cache.lookup(req);
+			if (res) return res;
+
+			let { pathname } = new URL(req.url);
+
+			// static assets
+			if (pathname.startsWith(prefix)) {
+				res = await env.ASSETS.fetch(req);
+
+				res = new Response(res.body, {
+					headers: {
+						// include original cache headers, minus cache-control which
+						// is overridden, and etag which is no longer useful
+						'cache-control': 'public, immutable, max-age=31536000',
+						'content-type': res.headers.get('content-type'),
+						'x-robots-tag': 'noindex'
+					}
+				});
+			} else {
+				// prerendered pages and index.html files
+				pathname = pathname.replace(/\/$/, '') || '/';
+
+				let file = pathname.substring(1);
+
+				try {
+					file = decodeURIComponent(file);
+				} catch (err) {
+					// ignore
+				}
+
+				if (
+					manifest.assets.has(file) ||
+					manifest.assets.has(file + '/index.html') ||
+					prerendered.has(pathname)
+				) {
+					res = await env.ASSETS.fetch(req);
+				} else {
+					// dynamically-generated pages
+					res = await server.respond(req, {
+						platform: { env, context },
+						getClientAddress() {
+							return req.headers.get('cf-connecting-ip');
+						}
+					});
+				}
+			}
+
+			// Writes to Cache only if allowed
+			return Cache.save(req, res, context);
+		} catch (e) {
+			return new Response('Error rendering route: ' + (e.message || e.toString()), { status: 500 });
+		}
+	}
+};
+
+export default worker;

packages/adapter-cloudflare/tsconfig.json

@@ -11,5 +11,5 @@
 			"@sveltejs/kit": ["../kit/types/index"]
 		}
 	},
-	"include": ["**/*.js", "ambient.d.ts"]
+	"include": ["index.js", "ambient.d.ts", "src/worker.ts"]
 }