Update README.md

README.md

@@ -3,8 +3,10 @@
 Next.js On-Demand Revalidation for Wordpress on the post update, revalidate specific paths on the post update.
 
 ## Installation
+
+### Pages Router
 - In your Next.js project add new file `/pages/api/revalidate.ts` with this code:
-```
+```ts
 import { NextApiRequest, NextApiResponse } from "next"
 
 export default async function handler(req: NextApiRequest, res: NextApiResponse) {
@@ -49,6 +51,110 @@ export default async function handler(req: NextApiRequest, res: NextApiResponse)
     }
 }
 ```
+### App Router (with tags support)
+- In your Next.js project add new file `/app/api/revalidate/route.ts` with this code:
+```ts
+import { revalidatePath, revalidateTag } from 'next/cache';
+import { headers } from 'next/headers';
+import { NextRequest } from 'next/server';
+
+/**
+ * Constants for HTTP Status codes.
+ */
+const STATUS_CODES = {
+	UNAUTHORIZED: 401,
+	PRECONDITION_FAILED: 412,
+	INTERNAL_SERVER_ERROR: 500,
+};
+
+const { REVALIDATE_SECRET_KEY } = process.env;
+
+if (!REVALIDATE_SECRET_KEY) {
+	throw new Error('Missing REVALIDATE_SECRET_KEY environment variable');
+}
+
+export async function PUT(request: NextRequest) {
+	const { paths, tags }: { paths?: string[]; tags?: string[] } =
+		await request.json();
+
+	console.log('Received paths:', paths);
+	console.log('Received tags:', tags);
+
+	const headersList = headers();
+	const authorizationHeader = headersList.get('authorization');
+
+	console.log('Authorization header:', authorizationHeader);
+
+	if (authorizationHeader !== `Bearer ${REVALIDATE_SECRET_KEY}`) {
+		console.error(`Invalid token: ${authorizationHeader}`);
+		return new Response(`Invalid token`, { status: STATUS_CODES.UNAUTHORIZED });
+	}
+
+	if (!paths && !tags) {
+		console.error(`Precondition Failed: Missing paths and tags`);
+		return new Response(`Precondition Failed: Missing paths and tags`, {
+			status: STATUS_CODES.PRECONDITION_FAILED,
+		});
+	}
+
+	let revalidatePaths: string[] = [];
+	let correctTags: string[] = [];
+
+	if (paths) {
+		revalidatePaths = paths.filter((path) => path.startsWith('/'));
+
+		console.log('Filtered correct paths:', revalidatePaths);
+	}
+
+	if (tags) {
+		correctTags = tags.filter((tag) => typeof tag === 'string');
+		console.log('Filtered correct tags:', correctTags);
+	}
+
+	try {
+		revalidatePaths.forEach((path) => {
+			revalidatePath(path);
+		});
+
+		correctTags.forEach((tag) => {
+			revalidateTag(tag);
+		});
+
+		console.log(
+			`${new Date().toJSON()} - Paths and tags revalidated: ${revalidatePaths.join(
+				', '
+			)} and ${correctTags.join(', ')}`
+		);
+
+		return new Response(
+			JSON.stringify({
+				revalidated: true,
+				message: `Paths and tags revalidated: ${revalidatePaths.join(
+					', '
+				)} and ${correctTags.join(', ')}`,
+			}),
+			{
+				status: 200,
+				headers: {
+					'Content-Type': 'application/json',
+				},
+			}
+		);
+	} catch (err: unknown) {
+		let message: string;
+
+		if (err instanceof Error) {
+			message = err.message;
+		} else {
+			message = 'An error occurred';
+		}
+		console.error('Revalidation error:', message);
+		return new Response(message, {
+			status: STATUS_CODES.INTERNAL_SERVER_ERROR,
+		});
+	}
+}
+```
 - Add `REVALIDATE_SECRET_KEY` env variable to your Next.js with Revalidate Secret Key value you added in the Plugin Settings.
 ___