Add migrate command for initializing open-next for existing Next.js projects

.changeset/add-init-command.md

@@ -0,0 +1,9 @@
+---
+"@opennextjs/cloudflare": minor
+---
+
+feature: add `migrate` command to set up OpenNext for Cloudflare adapter
+
+This command helps users migrate existing Next.js applications to the OpenNext Cloudflare adapter by automatically setting up all necessary configuration files, dependencies, and scripts.
+
+To use the command simply run: `npx opennextjs-cloudflare migrate`

packages/cloudflare/src/cli/build/utils/create-config-files.ts

@@ -1,9 +1,7 @@
-import { cpSync, existsSync, readFileSync, writeFileSync } from "node:fs";
-import { join } from "node:path";
-
-import { getPackageTemplatesDirPath } from "../../../utils/get-package-templates-dir-path.js";
 import type { ProjectOptions } from "../../project-options.js";
 import { askConfirmation } from "../../utils/ask-confirmation.js";
+import { createOpenNextConfigFile, findOpenNextConfig } from "../../utils/open-next-config.js";
+import { createWranglerConfigFile, findWranglerConfig } from "../../utils/wrangler-config.js";
 
 /**
  * Creates a `wrangler.jsonc` file for the user if a wrangler config file doesn't already exist,
@@ -13,12 +11,8 @@ import { askConfirmation } from "../../utils/ask-confirmation.js";
  *
  * @param projectOpts The options for the project
  */
-export async function createWranglerConfigIfNotExistent(projectOpts: ProjectOptions): Promise<void> {
-	const possibleExts = ["toml", "json", "jsonc"];
-
-	const wranglerConfigFileExists = possibleExts.some((ext) =>
-		existsSync(join(projectOpts.sourceDir, `wrangler.${ext}`))
-	);
+export async function createWranglerConfigIfNonExistent(projectOpts: ProjectOptions): Promise<void> {
+	const wranglerConfigFileExists = Boolean(findWranglerConfig(projectOpts.sourceDir));
 	if (wranglerConfigFileExists) {
 		return;
 	}
@@ -36,54 +30,7 @@ export async function createWranglerConfigIfNotExistent(projectOpts: ProjectOpti
 		return;
 	}
 
-	let wranglerConfig = readFileSync(join(getPackageTemplatesDirPath(), "wrangler.jsonc"), "utf8");
-
-	const appName = getAppNameFromPackageJson(projectOpts.sourceDir) ?? "app-name";
-
-	wranglerConfig = wranglerConfig.replaceAll('"<WORKER_NAME>"', JSON.stringify(appName.replaceAll("_", "-")));
-
-	const compatDate = await getLatestCompatDate();
-	if (compatDate) {
-		wranglerConfig = wranglerConfig.replace(
-			/"compatibility_date": "\d{4}-\d{2}-\d{2}"/,
-			`"compatibility_date": ${JSON.stringify(compatDate)}`
-		);
-	}
-
-	writeFileSync(join(projectOpts.sourceDir, "wrangler.jsonc"), wranglerConfig);
-}
-
-function getAppNameFromPackageJson(sourceDir: string): string | undefined {
-	try {
-		const packageJsonStr = readFileSync(join(sourceDir, "package.json"), "utf8");
-		const packageJson: Record<string, string> = JSON.parse(packageJsonStr);
-		if (typeof packageJson.name === "string") return packageJson.name;
-	} catch {
-		/* empty */
-	}
-}
-
-export async function getLatestCompatDate(): Promise<string | undefined> {
-	try {
-		const resp = await fetch(`https://registry.npmjs.org/workerd`);
-		const latestWorkerdVersion = (
-			(await resp.json()) as {
-				"dist-tags": { latest: string };
-			}
-		)["dist-tags"].latest;
-
-		// The format of the workerd version is `major.yyyymmdd.patch`.
-		const match = latestWorkerdVersion.match(/\d+\.(\d{4})(\d{2})(\d{2})\.\d+/);
-
-		if (match) {
-			const [, year, month, date] = match;
-			const compatDate = `${year}-${month}-${date}`;
-
-			return compatDate;
-		}
-	} catch {
-		/* empty */
-	}
+	await createWranglerConfigFile(projectOpts.sourceDir);
 }
 
 /**
@@ -95,9 +42,8 @@ export async function getLatestCompatDate(): Promise<string | undefined> {
  * @return The path to the created source file
  */
 export async function createOpenNextConfigIfNotExistent(sourceDir: string): Promise<string> {
-	const openNextConfigPath = join(sourceDir, "open-next.config.ts");
-
-	if (!existsSync(openNextConfigPath)) {
+	const openNextConfigPath = findOpenNextConfig(sourceDir);
+	if (!openNextConfigPath) {
 		const answer = await askConfirmation(
 			"Missing required `open-next.config.ts` file, do you want to create one?"
 		);
@@ -106,7 +52,7 @@ export async function createOpenNextConfigIfNotExistent(sourceDir: string): Prom
 			throw new Error("The `open-next.config.ts` file is required, aborting!");
 		}
 
-		cpSync(join(getPackageTemplatesDirPath(), "open-next.config.ts"), openNextConfigPath);
+		return createOpenNextConfigFile(sourceDir);
 	}
 
 	return openNextConfigPath;

packages/cloudflare/src/cli/build/utils/files.ts

@@ -0,0 +1,23 @@
+import fs from "node:fs";
+
+/**
+ * Appends text to a file
+ *
+ * When the file does not exists, it is always created with the text content.
+ * When the file exists, the text is appended only when the predicate return `true`.
+ *
+ * @param filepath The path to the file.
+ * @param text The text to append to the file.
+ * @param condition A function that receives the current file content and returns `true` if the text should be appended to it, the condition is skipped when the file is being created.
+ */
+export function conditionalAppendFileSync(
+	filepath: string,
+	text: string,
+	condition: (fileContent: string) => boolean
+): void {
+	const fileExists = fs.existsSync(filepath);
+
+	if (!fileExists || condition(fs.readFileSync(filepath, "utf8"))) {
+		fs.appendFileSync(filepath, text);
+	}
+}

packages/cloudflare/src/cli/commands/build.ts

@@ -1,7 +1,7 @@
 import type yargs from "yargs";
 
 import { build as buildImpl } from "../build/build.js";
-import { createWranglerConfigIfNotExistent } from "../build/utils/index.js";
+import { createWranglerConfigIfNonExistent } from "../build/utils/index.js";
 import type { WithWranglerArgs } from "./utils.js";
 import {
 	compileConfig,
@@ -38,7 +38,7 @@ async function buildCommand(
 	// Note: We don't ask when a custom config file is specified via `--config`
 	//       nor when `--skipWranglerConfigCheck` is used.
 	if (!projectOpts.wranglerConfigPath && !args.skipWranglerConfigCheck) {
-		await createWranglerConfigIfNotExistent(projectOpts);
+		await createWranglerConfigIfNonExistent(projectOpts);
 	}
 
 	const wranglerConfig = await readWranglerConfig(args);