Laravel Meta Laravel Package

Getting Started

Minimal Setup

1. Installation:

   composer require kodeine/laravel-meta
   

   Publish the config (if needed):

   php artisan vendor:publish --provider="Kodeine\Meta\MetaServiceProvider"
   

2. Apply the Trait: Use the Metable trait in your Eloquent model:

   use Kodeine\Meta\Traits\Metable;
   
   class Post extends Model
   {
       use Metable;
   }
   

3. First Use Case: Access or modify metadata fluently:

   $post = Post::find(1);
   $post->meta('author_name', 'John Doe'); // Set meta
   $post->meta('author_name');             // Get meta (returns 'John Doe')
   $post->meta('author_name', null);       // Unset meta
   

4. Configuration: Check config/meta.php for default settings (e.g., meta_column, meta_prefix).

Implementation Patterns

Core Workflows

1. CRUD Operations:

   // Set multiple meta keys at once
   $post->meta(['author_name' => 'Jane Smith', 'tags' => ['laravel', 'meta']]);
   
   // Check if meta exists
   if ($post->meta('author_name')) {
       // ...
   }
   
   // Delete a single meta key
   $post->meta('author_name', null);
   
   // Clear all meta data
   $post->clearMeta();
   

2. Integration with Eloquent Events: Use saving, saved, etc., to sync meta data:

   $post->saving(function ($model) {
       $model->meta('updated_at', now());
   });
   

3. Query Scopes: Filter models by meta data:

   // Find posts with a specific meta key
   $posts = Post::whereMeta('author_name', 'John Doe')->get();
   
   // Find posts with meta containing a value
   $posts = Post::whereMetaContains('tags', 'laravel')->get();
   

4. Caching Meta Data: Cache meta data for performance (e.g., using Laravel's cache):

   $post->meta('cached_value', Cache::get('key'), true); // Cache on set
   

5. Serialization: Automatically serialize/deserialize meta values (e.g., arrays):

   $post->meta('tags', ['laravel', 'meta']); // Automatically serialized
   $post->meta('tags'); // Returns ['laravel', 'meta']
   

6. Model Casting: Cast meta values to custom types (e.g., Carbon instances):

   protected $casts = [
       'meta.published_at' => 'datetime',
   ];
   

Gotchas and Tips

Common Pitfalls

1. Column Name Conflicts:

   • Ensure meta_column in config doesn’t conflict with existing columns.
   • Default: meta_data (stores JSON-encoded meta key-value pairs).

2. Serialization Issues:

   • Non-serializable values (e.g., closures, resources) will throw errors.
   • Fix: Explicitly cast or handle serialization in meta() calls.

3. Mass Assignment Risks:

   • Meta data is not protected by default. Use $guarded or $fillable:

     protected $guarded = ['meta.*']; // Block mass assignment for meta
     

4. Performance with Large Meta Data:

   • Avoid storing large binary data (e.g., files) in meta.
   • Tip: Use whereMeta sparingly on large datasets; add database indexes to meta_column.

5. Laravel 8+ Quirks:

   • If using Laravel 8+, ensure useHashedIds() or other model behaviors don’t interfere with meta queries.

6. Testing Meta Data:

   • Reset meta data in tests:

     $post->clearMeta();
     $post->save();
     

Debugging Tips

1. Inspect Raw Meta Data:

   dd($post->getMeta()); // Raw array of all meta data
   

2. Check Database Storage:

   SELECT meta_data FROM posts WHERE id = 1;
   

   • Verify JSON structure matches expectations.

3. Enable Query Logging:

   \DB::enableQueryLog();
   $posts = Post::whereMeta('key', 'value')->get();
   dd(\DB::getQueryLog());
   

Extension Points

1. Custom Meta Storage: Override getMetaSource() to use a different storage backend (e.g., Redis):

   public function getMetaSource()
   {
       return Cache::store('redis');
   }
   

2. Meta Events: Listen for meta changes via events:

   event(new MetaUpdated($post, 'author_name', 'John Doe'));
   

3. Dynamic Meta Accessors: Use meta() with dynamic keys:

   $key = 'dynamic_' . $id;
   $post->meta($key, 'value');
   

4. Meta Validation: Validate meta data in boot():

   static::saving(function ($model) {
       if ($model->meta('price') && $model->meta('price') < 0) {
           throw new \Exception('Price cannot be negative');
       }
   });
   

5. Fallback Values: Provide defaults in meta():

   $author = $post->meta('author_name', 'Anonymous');