A Quick Guide to Creating Laravel Factories and Seeders

I often find myself back to the Laravel documentation whenever I need to create new factories and seeders for my projects, whether they’re learning exercises, hobby projects, or real-world applications (bored doing the same actions every time). To make this process easy, I’ve decided to create a guide that I can refer to whenever needed, saving time and avoiding the need to search through extensive documentation. If this guide helps someone else, that would be a great thing!

Let’s assume we have a User/Posts relationship, meaning each user can have one or more posts, and each post belongs to a user.

What is a Factory?

A Factory in Laravel is a class to generate test data for your application. This is useful for local development and staging environments, providing a lot of benefits. Laravel allows you to create a factory for each model you have.

What are Seeders?

Seeders in Laravel are used to populate your database with data using seed classes, which is especially useful for testing purposes.

Generating New Factories

To create a new factory, run the following command:

php artisan make:factory PostFactory

You will find your factory class under the database/factories directory. Here is an example of defining your factory:

public function definition(): array
{
    return [
        'title' => $this->faker->sentence,
        'content' => $this->faker->paragraph,
        'user_id' => User::factory(),
    ];
}

Generating Seeders

To create a new seeder, run the following command:

php artisan make:seeder PostSeeder

You will find the seeder class under the database/seeders directory. Here is an example of the run function within this class:

public function run(): void
{
    Post::factory()
        ->count(20)
        ->create();
}

In the same directory, you will find the DatabaseSeeder class. Ensure it includes all your seeders:

public function run(): void
{
    // \App\Models\User::factory(10)->create();

    // \App\Models\User::factory()->create([
    //     'name' => 'Test User',
    //     'email' => 'test@example.com',
    // ]);

    $this->call([
        PostSeeder::class,
        ..,
        ..
    ]);
}

Running Migrations and Seeding the Database

First, run the database migrations:

php artisan migrate

Then, seed the database:

php artisan db:seed

Now you have test data in place. Enjoy!