Web Scraping With Node-Unblocker
Tutorial on using Node-Unblocker - a nodejs library - to avoid blocking while web scraping and using it to optimize web scraping stacks.
CSS selectors are much more widely used in NodeJS and Javascript ecosystems though for web scraping we might need more powerful features of XPath selectors.
There are few options available for XPath selectors. Most popular one in web scraping is the osmosis library:
const osmosis = require("osmosis");
const html = `
<a href="http://scrapfly.io/">link 1</a>
<a href="http://scrapfly.blog/">link 2</a>
`
osmosis
.parse(html)
.find('//a/@href')
.log(console.log);
Another alternative is the xmldom library:
import xpath from 'xpath';
import { DOMParser } from '@xmldom/xmldom'
const tree = new DOMParser().parseFromString(`
<body>
<h1>Page title</h1>
<p>some paragraph</p>
<a href="http://scrapfly.io/blog">some link</a>
</body>
`);
console.log({
// we can extract text of the node, which returns `Text` object:
title: xpath.select('//h1/text()', tree)[0].data,
// or a specific attribute value, which return `Attr` object:
url: xpath.select('//a/@href', tree)[0].value,
});