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Meta Model

The Meta model represents a key-value metadata entry associated with any Eloquent model via a polymorphic relation. It stores arbitrary metadata for models such as posts, products, users, etc., allowing extensibility without altering their main table.

Namespace​

JobMetric\Metadata\Models\Meta

Overview​

The Meta model is designed to store arbitrary metadata for models via a polymorphic relationship. It supports complex data types by marking values as JSON-encoded and provides a clean API for querying metadata.

Table Structure​

The metas table has the following structure:

  • id - Primary key
  • metaable_type - Model class name (polymorphic)
  • metaable_id - Model ID (polymorphic)
  • key - Metadata key (indexed)
  • value - Metadata value (text, nullable)
  • is_json - Boolean flag indicating if value is JSON
  • created_at - Timestamp
  • updated_at - Timestamp
  • Unique index on (metaable_type, metaable_id, key)

Relationships​

Metaable (Polymorphic)​

Get the parent model that owns this metadata:

$meta = Meta::find(1);
$product = $meta->metaable;
// => Product model instance

Returns: MorphTo - Polymorphic relationship

Available Methods​

Query Scopes​

The model provides query scopes for common operations:

// Filter by metaable type
Meta::whereMetaableType(Product::class)->get();

// Filter by metaable ID
Meta::whereMetaableId(1)->get();

// Filter by key
Meta::whereKey('color')->get();

// Filter by value
Meta::whereValue('red')->get();

// Filter by JSON flag
Meta::whereIsJson(true)->get();

Direct Usage​

While you typically interact with metadata through the HasMeta trait, you can also work with the Meta model directly:

use JobMetric\Metadata\Models\Meta;

// Create metadata directly
$meta = Meta::create([
    'metaable_type' => Product::class,
    'metaable_id' => 1,
    'key' => 'color',
    'value' => 'red',
    'is_json' => false,
]);

// Query metadata
$colorMetas = Meta::where('key', 'color')->get();

// Find metadata for a specific model
$productMetas = Meta::where('metaable_type', Product::class)
    ->where('metaable_id', 1)
    ->get();

JSON Values​

When storing arrays or objects, the value is automatically JSON-encoded and is_json is set to true:

$meta = Meta::create([
    'metaable_type' => Product::class,
    'metaable_id' => 1,
    'key' => 'dimensions',
    'value' => json_encode(['width' => 10, 'height' => 20]),
    'is_json' => true,
]);

// When retrieving, decode if needed
$dimensions = $meta->is_json 
    ? json_decode($meta->value, true) 
    : $meta->value;