minify/docs/CustomSource.wiki.md

In groupsConfig.php, usually you specify source file paths using strings like /path/to/file.js or //js/file1.js (Minify expands this to "{$_SERVER['DOCUMENT_ROOT']}/js/file1.js" ).

Instead of a string, you may substitute an instance of class Minify_Source. This allows you to customize how minification is applied, and/or pull content from a non-file location (e.g. a URL).

Example: filepath

In the $spec array, set the key filepath to produce a source based on a file path:

$src1 = new Minify_Source(array(
    'filepath' => '//js/file1.js',
));
$src2 = new Minify_Source(array(
    'filepath' => '//js/file2.js',
));

return [
    'js' => [$src1, $src2]
];

Note the above is functionally identical to:

return [
    'js' => ['//js/file1.js', '//js/file2.js'],
];

Example: Specify a different minifier or none at all

To change minifier, set minifier to a callback* or the empty string (for none):

*Prepare for groupsConfig.php to be executed more than once. (This is likely if you're using the functions in /min/utils.php.) In practice this just means making sure functions are conditionally defined if they don't already exist, etc.

$src1 = new Minify_Source(array(
    'filepath' => '//js/file1.js',
    'minifier' => 'myJsMinifier',
));
$src2 = new Minify_Source(array(
    'filepath' => '//js/file2.js',
    'minifier' => 'Minify::nullMinifier', // don't compress
));

In the above, JmyJsMinifier() is only called when the contents of $src1 is needed.

*Do not use create_function() or anonymous functions for the minifier. The internal names of these function tend to vary, causing endless cache misses, killing performance and filling cache storage up.

Non-File Sources

You're not limited to flat js/css files, but without filepath, the $spec array must contain these keys:

• id a unique string id for this source. (e.g. 'my source')
• getContentFunc a callback that returns the content. The function is only called when the cache is rebuilt.
• contentType Minify::TYPE_JS or Minify::TYPE_CSS
• lastModified a timestamp indicating when the content last changed. (If you can't determine this quickly, you can "fake" it using a step function, causing the cache to be periodically rebuilt.)

Example: Content from a URL

Here we want to fetch javascript from a URL. We don't know when it will change, so we use a stepping expression to re-fetch it every midnight:

if (! function_exists('src1_fetch')) {
    function src1_fetch() {
        return file_get_contents('http://example.org/javascript.php');
    }
}
$src1 = new Minify_Source([
    'id' => 'source1',
    'getContentFunc' => 'src1_fetch',
    'contentType' => Minify::TYPE_JS,    
    'lastModified' => ($_SERVER['REQUEST_TIME'] - $_SERVER['REQUEST_TIME'] % 86400),
]);

If you know that the URL content only depends on a few local files, you can use the maximum of their mtimes as the lastModified key:

$src1 = new Minify_Source([
    'id' => 'source1',
    'getContentFunc' => 'src1_fetch',
    'contentType' => Minify::TYPE_JS,
    'lastModified' => max(
        filemtime('/path/to/javascript.php')
        ,filemtime('/path/to/javascript_input.css')
    ),
]);

Performance Considerations

Be aware that all the code you put in groupsConfig.php will be evaluated upon every request like /min/g=..., so make it as light as possible.

If you wish to keep groupsConfig.php "clean", you can alternately create a separate PHP script that manually sets up sources, caching, options, and calls Minify::serve().

// myServer.php
/**
 * This script implements a Minify server for a single set of sources.
 * If you don't want '.php' in the URL, use mod_rewrite...
 */

require __DIR__ . '/vendor/autoload.php';

// setup Minify
$cache = new Minify_Cache_File();
$minify = new Minify($cache);
$env = new Minify_Env();
$sourceFactory = new Minify_Source_Factory($env, [], $cache);
$controller = new Minify_Controller_Files($env, $sourceFactory);

function src1_fetch() {
    return file_get_contents('http://example.org/javascript.php');
}

// setup sources
$sources = [];
$sources[] = new Minify_Source([
    'id' => 'source1',
    'getContentFunc' => 'src1_fetch',
    'contentType' => Minify::TYPE_JS,
    'lastModified' => max(
        filemtime('/path/to/javascript.php'),
        filemtime('/path/to/javascript_input.js')
    ),
]);
$sources[] = '//file2.js';
$sources[] = '//file3.js';

// setup serve and controller options
$options = [
    'files' => $sources,
    'maxAge' => 86400,
];

// handle request
$minify->serve($controller, $options);