How to minify JS in PHP easily…Or something else

Question

I've done some looking around, but I'm still confused a bit.

I tried Crockford's JSMin, but Win XP can't unzip the executable file for some reason.

What I really want though is a simple and easy-to-use JS minifier that uses PHP to minify JS code--and return the result.

The reason why is because: I have 2 files (for example) that I'm working between: scripts.js and scripts_template.js

scripts_template is normal code that I write out--then I have to minify it and paste the minified script into scripts.js--the one that I actually USE on my website.

I want to eradicate the middle man by simply doing something like this on my page:

<script type="text/javascript" src="scripts.php"></script>

And then for the contents of scripts.php:

<?php include("include.inc"); header("Content-type:text/javascript"); echo(minify_js(file_get_contents("scripts_template.js")));

This way, whenever I update my JS, I don't have to constantly go to a website to minify it and re-paste it into scripts.js--everything is automatically updated.

Yes, I have also tried Crockford's PHP Minifier and I've taken a look at PHP Speedy, but I don't understand PHP classes just yet...Is there anything out there that a monkey could understand, maybe something with RegExp?

How about we make this even simpler?

I just want to remove tab spaces--I still want my code to be readable.

It's not like the script makes my site lag epically, it's just anything is better than nothing.

Tab removal, anyone? And if possible, how about removing completely BLANK lines?

Answer 1

Depending on the restrictions of your server (eg, not running in safe mode), perhaps you can also look beyond PHP for a minifier and run it using shell_exec(). For instance, if you can run Java on your server, put a copy of YUI Compressor on the server and use it directly.

Then scripts.php would be something like:

<?php 

  $cmd = "java -cp [path-to-yui-dir] -jar [path-to-yuicompressor.jar] [path-to-scripts_template.js]";

  echo(shell_exec($cmd));

?>

Other suggestion: build the minification step into your development workflow, before you deploy to the server. For example I set up my Eclipse PHP projects to compress JS and CSS files into a "build" folder. Works like a charm.

Answer 2

Take a look at Assetic, a great asset management library in PHP. It is well integrated with Symfony2 and widely used.

https://github.com/kriswallsmith/assetic

Answer 3

Using "PHPWee": https://github.com/searchturbine/phpwee-php-minifier (which also uses JSmin), I pushed @Robert K solution a little bit further.

This solution allows minifying both CSS and JS files. If the non-minified file cannot be found, it will return an empty string. If the minified file is older than the non-minified, it will try to create it. It will create a sub-folder for the minified file if it doesn't exist. If the method can minify the file successfully, it returns it either in a <script> (javascript) or a <link> (CSS) tag. Otherwise, the method will return the non-minified version in the proper tag.

Note: tested with PHP 7.0.13

/**
* Try to minify the JS/CSS file. If we are not able to minify,
*   returns the path of the full file (if it exists).
*
* @param $matches Array
*   0 = Full partial path
*   1 = Path without the file
*   2 = File name and extension
*
* @param $fileType Boolean
*   FALSE: css file.
*   TRUE: js file
*
* @return String
*/
private static function createMinifiedFile(array $matches, bool $fileType)
{
    if (strpos($matches[1], 'shared_code') !== false) {

        $path = realpath(dirname(__FILE__)) . str_replace(
            'shared_code',
            '..',
            $matches[1]
        );

    } else {

        $path = realpath(dirname(__FILE__)) .
            "/../../" . $matches[1];
    }

    if (is_file($path . $matches[2])) {

        $filePath = $link = $matches[0];

        $min = 'min/' . str_replace(
            '.',
            '.min.',
            $matches[2]
        );

        if (!is_file($path . $min) or 
            filemtime($path . $matches[2]) > 
            filemtime($path . $min)
        ) {

            if (!is_dir($path . 'min')) {

                mkdir($path . 'min');   
            }

            if ($fileType) { // JS

                $minified = preg_replace(
                        array(
                            '/(\))\R({)/',
                            '/(})\R/'
                        ),
                        array(
                            '$1$2',
                            '$1'
                        ),
                        Minify::js(
                        (string) file_get_contents(
                            $path . $matches[2]
                        )
                    )
                );

            } else { // CSS

                $minified = preg_replace(
                    '@/\*(?:[\r\s\S](?!\*/))+\R?\*/@', //deal with multiline comments
                    '',
                    Minify::css(
                        (string) file_get_contents(
                            $path . $matches[2]
                        )
                    )
                );
            }

            if (!empty($minified) and file_put_contents(
                    $path . $min, 
                    $minified 
                )
            ) {

                $filePath = $matches[1] . $min;
            }

        } else { // up-to-date

            $filePath = $matches[1] . $min;
        }

    } else { // full file doesn't exists

        $filePath = "";
    }

    return $filePath;
}

/**
* Return the minified version of a CSS file (must end with the .css extension).
*   If the minified version of the file is older than the full CSS file,
*   the CSS file will be shrunk.
*
*   Note: An empty string will be return if the CSS file doesn't exist.
*
*   Note 2: If the file exists, but the minified file cannot be created, 
*       we will return the path of the full file.
*
* @link https://github.com/searchturbine/phpwee-php-minifier Source
*
* @param $path String name or full path to reach the CSS file.
*   If only the file name is specified, we assume that you refer to the shared path.
*
* @return String
*/
public static function getCSSMin(String $path)
{
    $link = "";
    $matches = array();

    if (preg_match(
            '@^(/[\w-]+/view/css/)?([\w-]+\.css)$@',
            $path,
            $matches
        )
    ) {

        if (empty($matches[1])) { // use the default path

            $matches[1] = self::getCssPath();

            $matches[0] = $matches[1] . $matches[2];
        }

        $link = self::createMinifiedFile($matches, false);

    } else {

        $link = "";
    }

    return (empty($link) ?
        '' :
        '<link rel="stylesheet" href="' . $link . '">'
    );
}

/**
* Return the path to fetch CSS sheets.
* 
* @return String
*/
public static function getCssPath()
{
    return '/shared_code/css/' . self::getCurrentCSS() . "/";
}

/**
* Return the minified version of a JS file (must end with the .css extension).
*   If the minified version of the file is older than the full JS file,
*   the JS file will be shrunk.
*
*   Note: An empty string will be return if the JS file doesn't exist.
*
*   Note 2: If the file exists, but the minified file cannot be created, 
*       we will return the path of the full file.
*
* @link https://github.com/searchturbine/phpwee-php-minifier Source
*
* @param $path String name or full path to reach the js file.
*
* @return String
*/
public static function getJSMin(String $path)
{
    $matches = array();

    if (preg_match(
            '@^(/[\w-]+(?:/view)?/js/)([\w-]+\.js)$@',
            $path,
            $matches
        )
    ) {
        $script = self::createMinifiedFile($matches, true);

    } else {

        $script = "";
    }

    return (empty($script) ? 
        '' :
        '<script src="' . $script . '"></script>'
    );
}

In a (Smarty) template, you might use those methods like this:

{$PageController->getCSSMin("main_frame.css")}
//Output: <link rel="stylesheet" href="/shared_code/css/default/min/main_frame.min.css">

{$PageController->getCSSMin("/gem-mechanic/view/css/gem_mechanic.css")}
//Output: <link rel="stylesheet" href="/gem-mechanic/view/css/min/gem_mechanic.min.css">

{$PageController->getJSMin("/shared_code/js/control_utilities.js")}
//Output: <script src="/shared_code/js/min/control_utilities.min.js"></script>

{$PageController->getJSMin("/PC_administration_interface/view/js/error_log.js")}
//Output: <script src="/PC_administration_interface/view/js/min/error_log.min.js"></script>

Unit tests:

/**
* Test that we can minify CSS files successfully.
*/
public function testGetCSSMin()
{
    //invalid style
    $this->assertEmpty(
        PageController::getCSSMin('doh!!!')
    );


    //shared style
    $path = realpath(dirname(__FILE__)) . '/../css/default/min/main_frame.min.css';

    if (is_file($path)) {

        unlink ($path);
    }

    $link = PageController::getCSSMin("main_frame.css");

    $this->assertNotEmpty($link);

    $this->assertEquals(
        '<link rel="stylesheet" href="/shared_code/css/default/min/main_frame.min.css">',
        $link
    );

    $this->validateMinifiedFile($path);


    //project style
    $path = realpath(dirname(__FILE__)) . '/../../gem-mechanic/view/css/min/gem_mechanic.min.css';

    if (is_file($path)) {

        unlink ($path);
    }

    $link = PageController::getCSSMin("/gem-mechanic/view/css/gem_mechanic.css");

    $this->assertNotEmpty($link);

    $this->assertEquals(
        '<link rel="stylesheet" href="/gem-mechanic/view/css/min/gem_mechanic.min.css">',
        $link
    );

    $this->validateMinifiedFile($path);
}

/**
* Test that we can minify JS files successfully.
*/
public function testGetJSMin()
{
    //invalid script
    $this->assertEmpty(
        PageController::getJSMin('doh!!!')
    );


    //shared script
    $path = realpath(dirname(__FILE__)) . '/../js/min/control_utilities.min.js';

    if (is_file($path)) {

        unlink ($path);
    }

    $script = PageController::getJSMin("/shared_code/js/control_utilities.js");

    $this->assertNotEmpty($script);

    $this->assertEquals(
        '<script src="/shared_code/js/min/control_utilities.min.js"></script>',
        $script
    );

    $this->validateMinifiedFile($path);


    //project script
    $path = realpath(dirname(__FILE__)) . '/../../PC_administration_interface/view/js/min/error_log.min.js';

    if (is_file($path)) {

        unlink ($path);
    }

    $script = PageController::getJSMin("/PC_administration_interface/view/js/error_log.js");

    $this->assertNotEmpty($script);

    $this->assertEquals(
        '<script src="/PC_administration_interface/view/js/min/error_log.min.js"></script>',
        $script
    );

    $this->validateMinifiedFile($path);
}

/**
* Make sure that the minified file exists and that its content is valid.
*
* @param $path String the path to reach the file
*/
private function validateMinifiedFile(string $path)
{
    $this->assertFileExists($path);

    $content = (string) file_get_contents($path);

    $this->assertNotEmpty($content);

    $this->assertNotContains('/*', $content);

    $this->assertEquals(
        0,
        preg_match(
            '/\R/',
            $content
        )
    );
}

Additional notes:

1. In phpwee.php I had to replace <? by <?php.
2. I had problems with the namespace (the function class_exists() was not able to find the classes even though they were in the same file). I solved this problem by removing the namespace in every file.

Answer 4

I have used a PHP implementation of JSMin by Douglas Crockford for quite some time. It can be a little risky when concatenating files, as there may be a missing semicolon on the end of a closure.

It'd be a wise idea to cache the minified output and echo what is cached so long as it's newer than the source file.

require 'jsmin.php';

if(filemtime('scripts_template.js') < filemtime('scripts_template.min.js')) {
  read_file('scripts_template.min.js');
} else {
  $output = JSMin::minify(file_get_contents('scripts_template.js'));
  file_put_contents('scripts_template.min.js', $output);
  echo $output;
}

You could also try JShrink. I haven't ever used it before, since I haven't had difficulty with JSMin before, but this code below should do the trick. I hadn't realized this, but JShrink requires PHP 5.3 and namespaces.

require 'JShrink/Minifier.php';

if(filemtime('scripts_template.js') < filemtime('scripts_template.min.js')) {
  read_file('scripts_template.min.js');
} else {
  $output = \JShrink\Minifier::minify(file_get_contents('scripts_template.js'));
  file_put_contents('scripts_template.min.js', $output);
  echo $output;
}