Question

So I have been using Minify to compress my JS and CSS which had all been going nicely until I needed to compress some dynamic php stylesheets.

I tried to use htaccess to fool it into thinking it was a css file, but I then realised it uses absolute file paths which would not be effected by mod_rewrite

Anyways whenever I point it at a php file, it always returns ‘400 Bad Request’. Any idea on how to solve this other than writing my own compression script?

Answer 1

I find the best way to deal with minifying and compressing stylesheets is to do it yourself. Check out this code:

<?php
header("Content-Type: text/css");
header("Last-Modified: ".gmdate('D, d M Y H:i:s', filemtime($_SERVER['DOCUMENT_ROOT'].$_SERVER['PHP_SELF']))." GMT");
header("Expires: ".gmdate('D, d M Y H:i:s', (filemtime($_SERVER['DOCUMENT_ROOT'].$_SERVER['PHP_SELF']) + 691200))." GMT");

//This GZIPs the CSS for transmission to the user
//making file size smaller and transfer rate quicker
ob_start("ob_gzhandler");
ob_start("compress");

//Function for compressing the CSS as tightly as possible
function compress($buffer) {
    //Remove CSS comments
    $buffer = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!', '', $buffer);
    //Remove tabs, spaces, newlines, etc.
    $buffer = str_replace(array("\r\n", "\r", "\n", "\t", '  ', '    ', '    '), '', $buffer);
    return $buffer;
}

//Main style
require_once($_SERVER['DOCUMENT_ROOT']."/templates/style/style.css");

//Other style
if($php_variable) {
    require_once($_SERVER['DOCUMENT_ROOT']."/templates/style/other.css");
}

ob_end_flush();
ob_end_flush();
?>

There’s a lot of things going on here, so let me explain.

Headers

• Setting the file type as being CSS.
• Setting the Last-Modified and Expires header for cache control (Setting at slightly over a week, you can change this).

Minify and GZIP

• Using ob_start, we tell it to GZIP this file as well as run a custom function compress.
• compress removes all CSS comments and white space when sending to to the browser. This means you can keep all your comments and spacing the way you like it in your source files for easier editing, but only send the bare minimum to the browser.

Style

• Using require to import the stylesheets. Do this for as many stylesheets as you’d like; They’ll all get delivered in a single HTTP request to the user.

Using Your New File

You’ll call on the file just as you would a normal CSS file.

<style type="text/css" src="/path/to/css-script.php"></style>

Conclusion

Using this method, you’re doing several awesome things.

• Provides the correct headers for cache’ing, making return visits to your site quick.
• Minifys all the contents to contain no extra white space or comments.
• Compresses the file using GZIP for smaller file size.
• Includes all your stylesheets in one HTTP request, great for optimization.
• Avoids using @import statements…which in itself is awesome.
• Allows you to keep multiple stylesheets and use PHP logic to include or not include them.
• Allows you to keep your source stylesheets spaced and commented as you like with no consequence to the visitors.

You can use this same method for JavaScript as well, though the compress function above is strictly for CSS so I would omit it.

Use this technique in combination with this cache control technique, and you’ve built yourself an awesome CSS/JS handler: How to force browser to reload cached CSS/JS files?