I’m working with a Laravel 11 project and need to link models together with a morph relationship. I’ve opted for a linking table called ModelHasModels which defines:

• source_id – id of the source model
• source_type – string for the source model
• target_id – id of the target model
• target_type – string for the target model

I have various models, a Site model and Affiliate model. affiliates can be linked to many sites, and sites would have affiliates.

I’ve defined my models, and inserted a row into the model_has_models table, but when querying the Site to get the affiliates I get nothing:

Querying:

Site::with('affiliates')->get(); <-- returns empty affiliates

Here’s the definition of each model:

Site

<?php

namespace AppModels;

use IlluminateDatabaseEloquentConcernsHasUlids;
use IlluminateDatabaseEloquentFactoriesHasFactory;
use IlluminateDatabaseEloquentModel;
use IlluminateDatabaseEloquentRelationsBelongsTo;
use IlluminateDatabaseEloquentRelationsMorphMany;
use IlluminateDatabaseEloquentRelationsMorphToMany;

class Site extends Model
{
    use HasUlids, HasFactory;

    /**
     * The attributes that are mass assignable.
     *
     * @var array<int, string>
     */
    protected $fillable = [
        'name',
        'description',
        'url',
        'is_enabled'
    ];

    /**
     * Get the attributes that should be cast.
     *
     * @return array<string, string>
     */
    protected function casts(): array
    {
        return [
            'is_enabled' => 'boolean'
        ];
    }

    /**
     * Define all of the related models for this model
     */
    public function models(): MorphMany
    {
        return $this->morphMany(ModelHasModel::class, 'source');
    }

    /**
     * Define all of the affiliates linked to this model
     */
    public function affiliates(): MorphToMany
    {
        return $this->morphedByMany(Affiliate::class, 'source', 'model_has_models', 'source_id', 'target_id');
    }

    /**
     * Link the model to the user
     */
    public function user(): BelongsTo
    {
        return $this->belongsTo(User::class);
    }
}

Affiliate

<?php

namespace AppModels;

use IlluminateDatabaseEloquentConcernsHasUlids;
use IlluminateDatabaseEloquentFactoriesHasFactory;
use IlluminateDatabaseEloquentModel;
use IlluminateDatabaseEloquentRelationsBelongsTo;
use IlluminateDatabaseEloquentRelationsMorphMany;
use IlluminateDatabaseEloquentRelationsMorphToMany;

class Affiliate extends Model
{
    use HasUlids, HasFactory;

    /**
     * The attributes that are mass assignable.
     *
     * @var array<int, string>
     */
    protected $fillable = [
        'name',
        'description',
        'api_key',
        'is_enabled'
    ];

    /**
     * Get the attributes that should be cast.
     *
     * @return array<string, string>
     */
    protected function casts(): array
    {
        return [
            'is_enabled' => 'boolean'
        ];
    }

    /**
     * Define all of the related models for this model
     */
    public function models(): MorphMany
    {
        return $this->morphMany(ModelHasModel::class, 'target');
    }

    /**
     * All of the sites that link to this model
     */
    public function sites(): MorphToMany
    {
        return $this->morphedByMany(Site::class, 'target', 'model_has_models', 'target_id', 'source_id');
    }

    /**
     * Link the model to the user
     */
    public function user(): BelongsTo
    {
        return $this->belongsTo(User::class);
    }
}

ModelHasModel

<?php

namespace AppModels;

use IlluminateDatabaseEloquentConcernsHasUlids;
use IlluminateDatabaseEloquentFactoriesHasFactory;
use IlluminateDatabaseEloquentModel;
use IlluminateDatabaseEloquentRelationsMorphTo;

class ModelHasModel extends Model
{
    use HasUlids, HasFactory;

    /**
     * The attributes that are mass assignable.
     *
     * @var array<int, string>
     */
    protected $fillable = [
        'source_id',
        'source_type',
        'target_id',
        'target_type'
    ];

    /**
     * Define the model that this model is derived from
     */
    public function source(): MorphTo
    {
        return $this->morphTo();
    }

    /**
     * Define the model that this model must link to
     */
    public function target(): MorphTo
    {
        return $this->morphTo();
    }
}

And I’ve created an entry in the model_has_models like the following:

INSERT INTO `model_has_models` (`id`, `source_type`, `source_id`, `target_type`, `target_id`, `created_at`, `updated_at`)
VALUES
    ('01HY083NK2THPY7A9M4SMKVVY3', 'App\Models\Site', '01hy07w8r8hc2v70h2zvbb6fz2', 'App\Models\Affiliate', '01hy07wp70a589gwpbqv0neh1a', '2024-05-16 08:26:10', '2024-05-16 08:26:12');

What am I missing?