CodeIgniter 4 Database Relationships

A simple solution to add relationships to your Codeigniter 4 application.

Installation

You can install this library from composer by running composer install immachakata/ci4-relationships

Defining Relationships

You can define as many relationships as you want using the hasMany or hasOne functions as needed. Here's an example of defining a single relationship for a users avatar and multiple relationship for a users links.

namespace App\Models;

use CodeIgniter\Model;
use CI4Extensions\Database\RelationshipsTrait;

class UserModel extends Model
{
    use RelationshipsTrait;
    
    ... 
    // declare relationships
    public function initialize(){
        $this->hasOne('avatar', AvatarModel::class, 'user_id');
        $this->hasMany('links', LinkModel::class, 'user_id');
    }
}

Using Relationships

When you perfom your query, explicitly mention the field name you want back as you defined in the initialize function. To do so, use the with($fieldName) function. Here's an example of retrieving the user avatar

class UserController extends BaseController
{
    public function index(){
        ...
        $this->respond([
            'user' => model(UserModel::class)->with('avatar')->findAll()
        ]);
    }
}

Credits

Forked from michalsn/codeigniter-nested-model