jsdomvsselectolax
jsdom is a pure JavaScript implementation of web standards, notably the WHATWG DOM and HTML standards, for use with Node.js. It simulates a browser environment in Node.js, allowing you to parse HTML, manipulate the DOM, and interact with web pages using the same APIs available in web browsers.
Key features for web scraping:
- Full DOM implementation Provides document.querySelector, document.querySelectorAll, and other standard DOM methods for traversing and manipulating parsed HTML.
- Browser-like environment Simulates window, document, navigator, and other browser globals, enabling code that was written for browsers to run in Node.js.
- JavaScript execution Can execute JavaScript embedded in HTML pages, including external scripts, making it possible to process pages that generate content dynamically (though much slower than a real browser).
- Standards-compliant parsing Uses the same HTML parsing algorithm as web browsers (the WHATWG HTML specification), ensuring accurate handling of malformed HTML.
- Cookie support Implements the tough-cookie library for cookie handling across requests.
For web scraping, jsdom is useful when you need more than simple CSS selector matching (what cheerio provides) but don't need a full browser. It's ideal for parsing complex HTML and running simple inline scripts without the overhead of Playwright or Puppeteer. However, for heavy JavaScript-rendered pages, a real browser automation tool is recommended.
selectolax is a fast and lightweight library for parsing HTML and XML documents in Python. It is designed to be a drop-in replacement for the popular BeautifulSoup library, with significantly faster performance.
selectolax uses a Cython-based parser to quickly parse and navigate through HTML and XML documents. It provides a simple and intuitive API for working with the document's structure, similar to BeautifulSoup.
To use selectolax, you first need to install it via pip by running pip install selectolax``.
Once it is installed, you can use theselectolax.html.fromstring()` function to parse an HTML document and create a selectolax object.
For example:
```
from selectolax.parser import HTMLParser
html_string = "
Hello, World!" root = HTMLParser(html_string).root print(root.tag) # html`
You can also use `selectolax.html.fromstring()` with file-like objects, bytes or file paths,
as well as `selectolax.xml.fromstring() for parsing XML documents.
Once you have a selectolax object, you can use the select() method to search for elements in the document using CSS selectors,
similar to BeautifulSoup. For example:
body = root.select("body")[0]
print(body.text()) # "Hello, World!"
Like BeautifulSoups find and find_all methods selectolax also supports searching using the search()`` method, which returns the first matching element,
and thesearch_all()`` method, which returns all matching elements.
Highlights
Example Use
Product A
$10.99Product B
$24.99
</body>
`;
const dom = new JSDOM(html); const document = dom.window.document;
// Use standard DOM APIs to extract data
const products = document.querySelectorAll('.product');
products.forEach(product => {
const name = product.querySelector('h2').textContent;
const price = product.querySelector('.price').textContent;
console.log(${name}: ${price});
});
// Fetch and parse a remote page JSDOM.fromURL('https://example.com').then(dom => { const title = dom.window.document.title; console.log('Page title:', title); }); ```
```python from selectolax.parser import HTMLParser
html_string = "
Hello, World!" root = HTMLParser(html_string).root print(root.tag) # htmluse css selectors:
body = root.select("body")[0] print(body.text()) # "Hello, World!"
find first matching element:
body = root.search("body") print(body.text()) # "Hello, World!"
or all matching elements:
html_string = "
paragraph1
paragraph2
" root = HTMLParser(html_string).root for el in root.search_all("p"): print(el.text())will print:
paragraph 1
paragraph 2
```