html5libvscascadia
html5lib is a pure-python library for parsing HTML. It is designed to conform to the WHATWG HTML specification, as is implemented by all major web browsers.
As html5lib is implemented in pure-python it is significantly slower than alternatives powered by lxml
(like parsel
or beautifulsoup
).
However, html5lib implements a more true html5 parsing which can represent HTML tree more correctly than alternatives.
cascadia is a library for Go that provides a CSS selector engine, allowing you to use CSS selectors to select elements from an HTML document.
It is built on top of the html package in the Go standard library, and provides a more efficient and powerful way to select elements from an HTML document.
Example Use
import html5lib
from html5lib import parse
html_doc = "<html><head><title>My Title</title></head><body></body></html>"
parsed = parse(html_doc)
title = parsed.getElementsByTagName("title")[0]
print(title.childNodes[0].nodeValue)
package main
import (
"fmt"
"github.com/andybalholm/cascadia"
"golang.org/x/net/html"
"strings"
)
func main() {
// Create an HTML string
html := `<html>
<body>
<div id="content">
<p>Hello, World!</p>
<a href="http://example.com">Example</a>
</div>
</body>
</html>`
// Parse the HTML string into a node tree
doc, err := html.Parse(strings.NewReader(html))
if err != nil {
fmt.Println("Error:", err)
return
}
// Compile the CSS selector
sel, err := cascadia.Compile("p")
if err != nil {
fmt.Println("Error:", err)
return
}
// Use the Selector.Match method to select elements from the document
matches := sel.Match(doc)
if len(matches) > 0 {
fmt.Println(matches[0].FirstChild.Data)
// > Hello, World!
}
}