Class Meta

Apply metadata to classes and their constants via annotation. Handy if you need to attach arbitrary data to lookups, enumerations, etc.

Installation

Install ClassMeta via Composer using the following command:

$ composer require ashleydawson/class-meta

Basic Usage

Apply metadata annotation to classes and constants:

<?php

namespace Acme\Enum;

use AshleyDawson\ClassMeta\Annotation\Meta;

/**
 * @Meta(data={"name"="Invoice Status Types"})
 */
class InvoiceStatus
{
    /**
     * @Meta(data={"name"="Draft", "description"="Invoice has not yet been sent to the customer"})
     */
    const DRAFT = 'draft';
    
    /**
     * @Meta(data={"name"="Sent", "description"="Invoice has been sent to the customer"})
     */
    const SENT = 'sent';
    
    /**
     * @Meta(data={"name"="Paid", "description"="Invoice has been paid by the customer"})
     */
    const PAID = 'paid';
    
    /**
     * @Meta(data={"name"="Void", "description"="Invoice is void and no longer billable"})
     */
    const VOID = 'void';
}

You can now access the metadata using the class meta manager:

use AshleyDawson\ClassMeta\ClassMetaManager;
use AshleyDawson\ClassMeta\Annotation\Meta;

$manager = new ClassMetaManager();

$classMeta = $manager->getClassMeta('Acme\Enum\InvoiceStatus');

// "Invoice Status Types" will be echoed
echo $classMeta->data['name'];

Get constant(s) metadata:

$constantsMeta = $manager->getClassConstantsMeta('Acme\Enum\InvoiceStatus');

// Echo all constant metadata
foreach ($constantsMeta as $meta) {
    echo $meta->data['name'] . PHP_EOL;
    echo $meta->data['description'] . PHP_EOL;
}

Get individual meta by value (i.e. the value of the constant):

$meta = $manager->getClassConstantMetaByValue('Acme\Enum\InvoiceStatus', InvoiceStatus::PAID);

// "Paid" will be echoed
echo $meta->data['name'];

Map the collection of constant meta for use in a select drop-down menu, for example:

$options = $manager->getMappedClassConstantsMeta('Acme\Enum\InvoiceStatus', function (Meta $meta, $i) {
    
    // Return items indexed by class constant value
    return [
        $meta->value, 
        $meta->data['name'],
    ];
    
    // OR
    
    // Return items indexed by an incremental integer, starting at zero
    return [
        $i, 
        $meta->data['name'],
    ];
    
});

echo '<select>';
foreach ($options as $value => $name) {
    echo "<option value=\"{$value}\">{$name}</option>";
}
echo '</select>';

Note: The optional argument $i passed to the map closure is the iteration number (starting at 0). Useful if you want to index the mapped collection instead of returning it as an associative array.

Grouped Metadata

Pass optional arbitrary groups to help organise your metadata:

<?php

namespace Acme\Enum;

use AshleyDawson\ClassMeta\Annotation\Meta;

/**
 * @Meta(data={"name"="Invoice Status Types"})
 */
class InvoiceStatus
{
    /**
     * @Meta(data={"name"="Draft"}, groups={"admin"})
     */
    const DRAFT = 'draft';
    
    /**
     * @Meta(data={"name"="Sent"}, groups={"admin"})
     */
    const SENT = 'sent';
    
    /**
     * @Meta(data={"name"="Paid"})
     */
    const PAID = 'paid';
    
    /**
     * @Meta(data={"name"="Void"}, groups={"admin"})
     */
    const VOID = 'void';
}

You can now access groups of metadata like so:

use AshleyDawson\ClassMeta\ClassMetaManager;

$manager = new ClassMetaManager();

$constantsMeta = $manager->getClassConstantsMeta('Acme\Enum\InvoiceStatus', ['admin']);

// Echo only constant metadata in "admin" group
foreach ($constantsMeta as $meta) {
    echo $meta->data['name'] . PHP_EOL;
}

$constantsMeta = $manager->getClassConstantsMeta('Acme\Enum\InvoiceStatus', ['Default']);

// Echo only constant metadata in "Default" group (i.e. `const PAID = 'paid'` metadata)
foreach ($constantsMeta as $meta) {
    echo $meta->data['name'] . PHP_EOL;
}

$constantsMeta = $manager->getClassConstantsMeta('Acme\Enum\InvoiceStatus', ['Default', 'admin']);

// Echo all constant metadata
foreach ($constantsMeta as $meta) {
    echo $meta->data['name'] . PHP_EOL;
}

Note: The "Default" group will contain metadata that is not assigned a group

If you need to get meta for all constants, even if they have groups assigned, use the special _all group name, like so:

$constantsMeta = $manager->getClassConstantsMeta('Acme\Enum\InvoiceStatus', ['_all']);

Cache

All metadata can be cached by simply passing a valid Doctrine cache provider to the class meta manager:

use Doctrine\Common\Cache\FilesystemCache;

$manager = new ClassMetaManager();
$manager->setCache(new FilesystemCache('/path/to/cache/dir'));

Cache is invalidated using the class file modify time, but you can also pass an optional TTL in seconds to the ClassMetaManager#setCache() method:

use Doctrine\Common\Cache\FilesystemCache;

$manager = new ClassMetaManager();
$manager->setCache(new FilesystemCache('/path/to/cache/dir'), 300); // Cache stale after 5 minutes

Tests

To run the ClassMeta test suite, install Composer dev dependencies and run:

$ bin/phpunit