Building a Scalable Web Scraper with Python and Scrapy
In one of my recent backend projects, I needed to extract structured data from multiple e-commerce sites at scale. After evaluating several tools, I chose Scrapy — a powerful Python framework for web scraping — and combined it with Docker and MongoDB for reliability and scalability.
This is how I built a maintainable, fault-tolerant scraper pipeline.
Why Scrapy?
While requests
+ BeautifulSoup
works for simple scripts, Scrapy offers:
- Built-in request throttling
- Middleware support (proxies, retries)
- Async crawling via Twisted
- Extensible pipelines
- Stats collection and logging
import scrapy
class ProductSpider(scrapy.Spider):
name = "product_spider"
start_urls = [
"https://example-shop.com/products?page=1"
]
def parse(self, response):
for product in response.css('.product-item'):
yield {
'name': product.css('.title::text').get(),
'price': product.css('.price::text').get(),
'url': product.css('a::attr(href)').get(),
}
# Follow pagination
next_page = response.css('.next-page::attr(href)').get()
if next_page:
yield response.follow(next_page, self.parse)