parse5vscssselect
parse5 is a Node.js library for parsing and manipulating HTML and XML documents. It is designed to be fast and flexible, and it is commonly used in web scraping and web development projects.
parse5 is used by popular libraries such as Angular, Lit, Cheerio and many more. Unlike Cheerio parse5 is a low level html parsing library that might be useful directly in web scraping without higher level abstraction.
cssselect is a BSD-licensed Python library to parse CSS3 selectors and translate them to XPath 1.0 expressions.
XPath 1.0 expressions can be used in lxml or another XPath engine to find the matching elements in an XML or HTML document.
cssselect is used by other popular Python packages like parsel and scrapy but can also be used on it's own to generate
valid XPath 1.0 expressions for parsing HTML and XML documents in other tools.
Note that because XPath selectors are more powerful than CSS selectors this translation is only possible one way. Converting XPath to CSS selectors is impractical and not supported by cssselect.
Example Use
const parse5 = require("parse5");
// parse string
const document = parse5.parse('<html><body>Hello World!</body></html>');
console.log(document);
// html tree can be traversed as javascript object:
const body = document.childNodes[1];
console.log(body.childNodes[0].value); // "Hello World!"
// and modified
const newElement = parse5.parseFragment('<p>New Element</p>');
body.appendChild(newElement.childNodes[0]);
console.log(parse5.serialize(document));
from cssselect import GenericTranslator, SelectorError
translator = GenericTranslator()
try:
expression = translator.css_to_xpath('div.content')
print(expression)
'descendant-or-self::div[@class and contains(concat(' ', normalize-space(@class), ' '), ' content ')]'
except SelectorError as e:
print(f'Invalid selector {e}')