Improving Laravel Factory Inserts to Speed Up Tests

Environment

• Laravel 5.x

Laravel's factory is powerful — it lets you create hierarchical data with intuitive syntax. However, it issues one insert per record, so it needs a bit of care.

// Create 5 users
factory(User::class, 3)
->create()
->each(function (User $user) {
    // Create 5 orders
    factory(Order::class, 5)
    ->create(['user_id' => $user->id])
    ->each(function (Order $order) {
        // Create 10 order_details
        factory(OrderDetail::class, 10);
    });
});

This code ends up issuing 3×5×10 = 150 inserts, which isn't great for performance. In cases like this, factory has a make function that only generates instances, which we can combine with insert.

// Create 3 users
$users = factory(User::class, 3)->make();
User::query()->insert($users->toArray());
// Find the users we just inserted
$users = User::query()->orderBy('created', 'desc')->limit(3)->get(); 
$users->each(function (User $user){

    // Create 5 orders
    $orders = factory(Order::class, 5)->make(['user_id' => $user->id]);
    Order::query()->insert($orders->toArray());
    // Find the orders we just inserted
    $orders = Order::query()->orderBy('created', 'desc')->limit(5)->get(); 

    $orders->each(function(Order $order){
        // Create 10 order_details
        $orderDetails = factory(OrderDetail::class, 10)->make([
            'user_id' => $user->id, 'order_id' => $order->id
        ]);
        OrderDetail::query()->insert($orderDetails->toArray());
    });
});

It's frustrating that this makes the code harder to follow, but it reduced the number of SQL executions from 150 down to 23 (1+1+3*(2+5*(1))).

After I wrote the code above, I got a code review comment saying "this way would bring it down even further." With the code below, the total number of SQL executions comes down to 5.

<?php 

// Create 3 users
$users = factory(User::class, 3)->make();
User::query()->insert($users->toArray());
$users = User::query()
    ->orderBy('created', 'desc')
    ->limit(3)
    ->get(); 

// Create the orders associated with the users
$orders = [];
$users->each(function (User $user){
    $orders[] = factory(Order::class, 5)
        ->make(['user_id' => $user->id])
        ->toArray();
});
Order::query()->insert($orders);

// Fetch the orders we just created (linked to the users),
// then create the order_details linked to those orders
$orderDetails = []
$orders = Order::query()
    ->whereIn('user_id', $users->pluck('user_id')
    ->toArray())
    ->get();
$orders->each(function(Order $order){
    $orderDetails[] = factory(OrderDetail::class, 10)
        ->make(['user_id' => $user->id, 'order_id' => $order->id])
        ->toArray());
});
OrderDetail::query()->insert($orderDetails);

You can also use the make function when you want to insert data you've already prepared as an array, by passing it through a factory.

$vegetables = [
    ['vegetable_group' => 1, 'name' => 'daikon radish'],
    ['vegetable_group' => 1, 'name' => 'pumpkin'],
    ['vegetable_group' => 1, 'name' => 'sweet potato'],
    ['vegetable_group' => 2, 'name' => 'garlic chives'],
    ['vegetable_group' => 2, 'name' => 'lettuce'],
    ...
    ...
    ['vegetable_group' => 9, 'name' => 'enoki mushroom'],
    ['vegetable_group' => 9, 'name' => 'shimeji mushroom'],
];

$insertVegetables = [];
foreach($vegetables as $v){
    $insertVegetables[] = factory(Vegetables::class)->make($v)->toArray();
}
Vegetables::query()->insert($insertVegetables);

Closing Thoughts

We had a project where the test suite was taking a long time to run, and wanting to improve that, I tuned it and wrote up what I did in this article. I'd be curious to know how larger projects design their test data.