How to Build a Price Comparison Website with Web Scraping

#javascript #ecommerce #webdev #tutorial

Price comparison sites make money through affiliate links. Here is how to build one.

Architecture

Cron Job → Scrapers → Database → Frontend
              ↓
    [Amazon, Walmart, eBay, etc.]

Multi-Store Scraper

async function comparePrice(product) {
  const [amazon, walmart, ebay] = await Promise.allSettled([
    scrapeAmazon(product),
    scrapeWalmart(product),
    scrapeEbay(product)
  ]);

  return [
    amazon.status === "fulfilled" ? amazon.value : null,
    walmart.status === "fulfilled" ? walmart.value : null,
    ebay.status === "fulfilled" ? ebay.value : null
  ].filter(Boolean).sort((a, b) => a.price - b.price);
}