[C3] fix: use a valid compatibility date for worker templates

Previously, we changed wrangler.toml to use the current date for the
compatibility_date setting in wrangler.toml when generating workers.
But this is almost always going to be new recent and results in a warning.

Now we look up the most recent compatibility date via npm on the workerd
package and use that instead.

Fixes #2385

.changeset/small-lies-thank.md

@@ -0,0 +1,14 @@
+---
+"create-cloudflare": patch
+---
+
+fix: use a valid compatibility date for worker templates
+
+Previously, we changed wrangler.toml to use the current date for the
+compatibility_date setting in wrangler.toml when generating workers.
+But this is almost always going to be new recent and results in a warning.
+
+Now we look up the most recent compatibility date via npm on the workerd
+package and use that instead.
+
+Fixes https://github.com/cloudflare/workers-sdk/issues/2385

.vscode/settings.json

@@ -37,6 +37,7 @@
 		"weakset",
 		"webassemblymemory",
 		"websockets",
+		"workerd",
 		"xxhash"
 	],
 	"cSpell.ignoreWords": [

packages/create-cloudflare/src/helpers/__tests__/command.test.ts

@@ -1,6 +1,7 @@
 import { spawn } from "cross-spawn";
 import { beforeEach, afterEach, describe, expect, test, vi } from "vitest";
 import whichPMRuns from "which-pm-runs";
+import { getWorkerdCompatibilityDate } from "../../workers";
 import {
 	detectPackageManager,
 	installPackages,
@@ -105,4 +106,9 @@ describe("Command Helpers", () => {
 		expect(pm.npm).toBe("yarn");
 		expect(pm.npx).toBe("npx");
 	});
+
+	test("getWorkerdCompatibilityDate()", async () => {
+		await getWorkerdCompatibilityDate();
+		expectSpawnWith("npm info workerd dist-tags.latest");
+	});
 });

packages/create-cloudflare/src/helpers/command.ts

@@ -9,11 +9,12 @@ import type { PagesGeneratorContext } from "types";
 
 type RunOptions = {
 	startText?: string;
-	doneText?: string;
+	doneText?: string | ((result: string) => string);
 	silent?: boolean;
 	captureOutput?: boolean;
 	env?: NodeJS.ProcessEnv;
 	cwd?: string;
+	transform?: (output: string) => string;
 };
 
 export const runCommand = async (
@@ -55,10 +56,16 @@ export const runCommand = async (
 	return await new Promise((resolve, reject) => {
 		cmd.on("close", (code) => {
 			if (code === 0) {
+				const transformedOutput =
+					opts?.transform?.(stripAnsi(output)) ?? stripAnsi(output);
 				if (opts?.doneText && !process.env.VITEST) {
-					s.stop(opts?.doneText);
+					const doneText =
+						typeof opts.doneText === "function"
+							? opts.doneText(transformedOutput)
+							: opts.doneText;
+					s.stop(doneText);
 				}
-				resolve(stripAnsi(output));
+				resolve(transformedOutput);
 			} else {
 				logRaw(output);
 				reject(code);

packages/create-cloudflare/src/workers.ts

@@ -147,8 +147,8 @@ async function updateFiles(ctx: Context) {
 	contents.wranglertoml = contents.wranglertoml
 		.replace(/^name = .+$/m, `name = "${ctx.project.name}"`)
 		.replace(
-			/^compatibility_date = .+$/m,
-			`compatibility_date = "${new Date().toISOString().substring(0, 10)}"`
+			/^compatibility_date\s=\s"<TBD>"$/m,
+			`compatibility_date = "${await getWorkerdCompatibilityDate()}"`
 		);
 
 	// write files
@@ -158,3 +158,28 @@ async function updateFiles(ctx: Context) {
 	);
 	await writeFile(paths.wranglertoml, contents.wranglertoml);
 }
+
+/**
+ * Look up the latest release of workerd and use its date as the compatibility_date
+ * configuration value for wrangler.toml.
+ *
+ * If the look up fails then we fall back to a well known date.
+ *
+ * @returns The latest compatibility date for workerd in the form "YYYY-MM-DD"
+ */
+export async function getWorkerdCompatibilityDate() {
+	return runCommand("npm info workerd dist-tags.latest", {
+		silent: true,
+		captureOutput: true,
+		startText: "Retrieving current workerd compatibility date",
+		transform: (result) => {
+			try {
+				const date = result.split(".")[1];
+				return `${date.slice(0, 4)}-${date.slice(4, 6)}-${date.slice(6, 8)}`;
+			} catch {
+				return "2023-05-18";
+			}
+		},
+		doneText: (output) => `${brandColor("compatibility date")} ${dim(output)}`,
+	}).then();
+}

packages/create-cloudflare/templates/chatgptPlugin/ts/wrangler.toml

@@ -1,3 +1,3 @@
-name = "cloudflare-workers-chatgpt-plugin-example"
+name = "<TBD>"
 main = "src/index.ts"
-compatibility_date = "2023-04-07"
+compatibility_date = "<TBD>"

packages/create-cloudflare/templates/common/js/wrangler.toml

@@ -1,6 +1,6 @@
 name = "<TBD>"
 main = "src/worker.js"
-compatibility_date = "2023-04-21"
+compatibility_date = "<TBD>"
 
 # # KV Namespace binding - For more information: https://developers.cloudflare.com/workers/runtime-apis/kv
 # [[kv_namespaces]]

packages/create-cloudflare/templates/common/ts/wrangler.toml

@@ -1,6 +1,6 @@
 name = "<TBD>"
 main = "src/worker.ts"
-compatibility_date = "2023-04-21"
+compatibility_date = "<TBD>"
 
 # # KV Namespace binding - For more information: https://developers.cloudflare.com/workers/runtime-apis/kv
 # [[kv_namespaces]]

packages/create-cloudflare/templates/simple/js/wrangler.toml

@@ -1,6 +1,6 @@
 name = "<TBD>"
 main = "src/worker.js"
-compatibility_date = "2023-04-21"
+compatibility_date = "<TBD>"
 
 # # KV Namespace binding - For more information: https://developers.cloudflare.com/workers/runtime-apis/kv
 # [[kv_namespaces]]

packages/create-cloudflare/templates/simple/ts/wrangler.toml

@@ -1,6 +1,6 @@
 name = "<TBD>"
 main = "src/worker.ts"
-compatibility_date = "2023-04-21"
+compatibility_date = "<TBD>"
 
 # # KV Namespace binding - For more information: https://developers.cloudflare.com/workers/runtime-apis/kv
 # [[kv_namespaces]]