SERA integration on Node

const express = require('express');
const app = express();
const port = 3000;


const seraEndpoint = 'SERA_ENDPOINT';
const seraToken = 'YOUR_TOKEN';
const n7AccessKey = 'N7_ACCESS_KEY';
//USE THIS - DURING POC PHASE for bot User-Agent regex :
const seraUserAgentPattern = /(n7TestUserAgent|google page speed|chrome-lighthouse|google-inspectiontool|PTST|GTmetrix|n7ua)/i;
//USE THIS - ON GOING LIVE ON SERA for bot User-Agent regex :
//const seraUserAgentPattern = /(n7TestUserAgent|google page speed|chrome-lighthouse|google-inspectiontool|PTST|GTmetrix|n7ua|googlebot|facebookexternalhit|bingbot)/i;
//USE THIS - ON GOING LIVE ON SERA for AI bots for bot User-Agent regex :
//const seraUserAgentPattern = /(openai|gptbot|claudebot|claude-user|perplexity-user|perplexity-bot|google-extended|google-cloudvertexbot|google-notebooklm|amazonbot|duckassistbot|metaai|metabotic|meta-externalagent|copilot|baiduspider)/i;
const seraAllowedExtnPattern = /^(|.+\.html|.+\.aspx|.+\.php)($|\?.*)/i;
const seraExludeQryPrmPattern = /\?(.*&)*(nsbp)=.*/i;
const seraExludePagePattern = /.*(\/static/|\/_next\/|\/api\/|\/login|\/logout|\/account\/|\/wishlist\/|\/cart\/|\/checkout\/|\/payment\/).*/i;

const sera = async (req, res, next) => {
	const { "user-agent": userAgent, "accept-encoding": acceptEncoding, accept, referer } = req.headers;

	if (req.method === "GET"
		&& seraUserAgentPattern.test(userAgent) 
		&& seraAllowedExtnPattern.test(req.url)
		&& !seraExludeQryPrmPattern.test(req.url)
		&& !seraExludePagePattern.test(req.url)
		&& !req.headers['x-nv-app']
		&& !req.headers['x-nv-sera-bypass']) {
		
		const headers = {
			'x-nv-sera-token': seraToken,
			'x-nv-access-key': n7AccessKey,
			'user-agent': userAgent || '',
			'accept-encoding': acceptEncoding || '',
			'accept': accept || '',
			'referer': referer || '',
		};

		const remoteUrl = `${seraEndpoint}${req.url.pathname}`; //USE THIS IF YOUR SITEMAP PAGE URLS DO NOT HAVE QUERYSTRING
		const remoteUrl = `${seraEndpoint}${req.url}`; //USE THIS IF YOUR SITEMAP PAGE URLS HAVE QUERYSTRING

		try {
			const response = await fetch(remoteUrl, { headers });
			if ((response.status === 200 || response.status === 410) && response.data) {
				res.status(response.status).send(response.data);
			}
			else {
				next();
			}
		} catch (error) {
			console.error('error downloading page:', error.message);
			next();
		}
	}
	else {
		next();
	}
}

app.use(sera);

app.get('/', (req, res) => {
	res.send('Hello World!')
})

app.listen(port, () => {
	console.log(`example app listening on port ${port}`)
})