50 stable releases (4 major)

5.0.0	Dec 15, 2023
4.0.0	Nov 13, 2022
3.0.17	~~Nov 2, 2022~~
3.0.15	Mar 17, 2022
1.1.3	Nov 14, 2018

#134 in Encoding

1,086 downloads per month
Used in 36 crates (17 directly)

MIT license

67KB
1K SLoC

HTML Minifier

This library can help you generate and minify your HTML code at the same time. It also supports to minify JS and CSS in <style>, <script> elements, and ignores the minification of <pre>, <code> and <textarea> elements.

HTML is minified by the following rules:

ASCII control characters (0x00-0x08, 0x11-0x1F, 0x7F) are always removed.
Comments can be optionally removed. (removed by default)
Useless whitespaces (spaces, tabs and newlines) are removed.
Whitespaces (spaces, tabs and newlines) are converted to a single '\x20' or a single '\n', if possible.
Empty attribute values are collapsed. (e.g <input readonly=""> => <input readonly> )
The inner HTML of all elements is minified except for the following elements:
- <pre>
- <textarea>
- <code> (optionally, minified by default)
- <style> (if the type attribute is unsupported)
- <script> (if the type attribute is unsupported)
JS code and CSS code in <script> and <style> elements are minified by minifier.

The original (non-minified) HTML doesn't need to be completely generated before using this library because this library doesn't do any deserialization to create DOMs.

Examples

use html_minifier::HTMLMinifier;

let mut html_minifier = HTMLMinifier::new();

html_minifier.digest("<!DOCTYPE html>   <html  ").unwrap();
html_minifier.digest("lang=  en >").unwrap();
html_minifier.digest("
<head>
    <meta name=viewport>
</head>
").unwrap();
html_minifier.digest("
<body class=' container   bg-light '>
    <input type='text' value='123   456' readonly=''  />

    123456
    <b>big</b> 789
    ab
    c
    中文
    字
</body>
").unwrap();
html_minifier.digest("</html  >").unwrap();

assert_eq!("<!DOCTYPE html> <html lang=en>
<head>
<meta name=viewport>
</head>
<body class='container bg-light'>
<input type='text' value='123   456' readonly/>
123456
<b>big</b> 789
ab
c
中文
字
</body>
</html>".as_bytes(), html_minifier.get_html());

use html_minifier::HTMLMinifier;

let mut html_minifier = HTMLMinifier::new();

html_minifier.digest("<pre  >   Hello  world!   </pre  >").unwrap();

assert_eq!(b"<pre>   Hello  world!   </pre>", html_minifier.get_html());

use html_minifier::HTMLMinifier;

let mut html_minifier = HTMLMinifier::new();

html_minifier.digest("<script type='  application/javascript '>   alert('Hello!')    ;   </script>").unwrap();

assert_eq!("<script type='application/javascript'>alert('Hello!')</script>".as_bytes(), html_minifier.get_html());

Write HTML to a Writer

If you don't want to store your HTML in memory (e.g. writing to a file instead), you can use the HTMLMinifierHelper struct which provides a low-level API that allows you to pass your output instance when invoking the digest method.

use html_minifier::HTMLMinifierHelper;

use std::fs::File;
use std::io::Read;

let mut input_file = File::open("tests/data/w3schools.com_tryhow_css_example_website.htm").unwrap();
let mut output_file = File::create("tests/data/index.min.html").unwrap();

let mut buffer = [0u8; 256];

let mut html_minifier_helper = HTMLMinifierHelper::new();

loop {
    let c = input_file.read(&mut buffer).unwrap();

    if c == 0 {
        break;
    }

    html_minifier_helper.digest(&buffer[..c], &mut output_file).unwrap();
}

Crates.io

https://crates.io/crates/html-minifier

Documentation

https://docs.rs/html-minifier

License

MIT

Dependencies

~1.4–2MB
~40K SLoC