Discounts - TALL Stack E-commerce Framework

Discounts allow you to create promotional offers for your customers. Shopper supports percentage and fixed amount discounts with flexible application rules, eligibility conditions, and usage limits.

Models

Shopper uses two models to manage discounts:

Model	Purpose
`Shopper\Core\Models\Discount`	The discount definition (code, type, value, rules)
`Shopper\Core\Models\DiscountDetail`	Polymorphic link connecting discounts to specific products or customers

The Discount model implements Shopper\Core\Models\Contracts\Discount. Neither model is configurable via config/shopper/models.php.

Database Schema

Discount Table

Column	Type	Nullable	Default	Description
`id`	bigint	no	auto	Primary key
`code`	string	no	-	Unique discount code
`type`	string	no	-	Discount type enum
`value`	integer	no	-	Discount value (percentage or cents)
`is_active`	boolean	no	false	Discount visibility
`apply_to`	string	no	-	Application scope enum
`min_required`	string	no	-	Requirement type enum
`min_required_value`	string	yes	null	Minimum value required
`eligibility`	string	no	-	Eligibility type enum
`usage_limit`	integer	yes	null	Maximum total uses
`usage_limit_per_user`	boolean	no	false	Limit one use per customer
`total_use`	integer	no	0	Current total usage count
`start_at`	datetime	no	-	Discount start date
`end_at`	datetime	yes	null	Discount end date (null = no expiry)
`zone_id`	bigint	yes	null	FK to zone (null = all zones)
`metadata`	json	yes	null	Additional custom data
`created_at`	timestamp	yes	null	Creation timestamp
`updated_at`	timestamp	yes	null	Last update timestamp

Discountable Table (Pivot)

Column	Type	Nullable	Description
`id`	bigint	no	Primary key
`condition`	string	yes	Condition type (apply_to, eligibility)
`total_use`	integer	no	Usage count for this relation
`discountable_id`	bigint	no	Polymorphic relation ID
`discountable_type`	string	no	Polymorphic relation type
`discount_id`	bigint	no	FK to discount

Discount Type

The DiscountType enum defines value types:

use Shopper\Core\Enum\DiscountType;

DiscountType::Percentage   // percentage - e.g., 10% off
DiscountType::FixedAmount  // fixed_amount - e.g., $10 off

Type	Database Value	Value Handling
Percentage	`percentage`	Stored as-is (10 = 10%)
Fixed Amount	`fixed_amount`	Stored in cents (1000 = $10.00)

Discount Application

The DiscountApplyTo enum defines where the discount applies:

use Shopper\Core\Enum\DiscountApplyTo;

DiscountApplyTo::Order     // order - Applies to entire order
DiscountApplyTo::Products  // products - Applies to specific products

Scope	Database Value	Description
Order	`order`	Discount applies to total order amount
Products	`products`	Discount applies only to linked products

Discount Eligibility

The DiscountEligibility enum defines who can use the discount:

use Shopper\Core\Enum\DiscountEligibility;

DiscountEligibility::Everyone   // everyone - All customers
DiscountEligibility::Customers  // customers - Specific customers only

Eligibility	Database Value	Description
Everyone	`everyone`	Any customer can use
Customers	`customers`	Only linked customers can use

Discount Requirements

The DiscountRequirement enum defines minimum conditions:

use Shopper\Core\Enum\DiscountRequirement;

DiscountRequirement::None     // none - No minimum
DiscountRequirement::Price    // price - Minimum order amount
DiscountRequirement::Quantity // quantity - Minimum items count

Requirement	Database Value	min_required_value
None	`none`	Not used
Price	`price`	Minimum amount in cents
Quantity	`quantity`	Minimum item count

Discount Condition

The DiscountCondition enum is used on the DiscountDetail pivot model to distinguish whether a linked record represents a product (the discount applies to) or a customer (who is eligible):

use Shopper\Core\Enum\DiscountCondition;

DiscountCondition::ApplyTo      // apply_to - Links a product to the discount
DiscountCondition::Eligibility  // eligibility - Links a customer to the discount

Relationships

Items (DiscountDetail)

use Shopper\Core\Enum\DiscountCondition;

// Get all discount items (products or customers)
$discount->items; // Collection of DiscountDetail models

// Add a product to discount
$discount->items()->create([
    'condition' => DiscountCondition::ApplyTo,
    'discountable_type' => Product::class,
    'discountable_id' => $productId,
]);

// Add eligible customer
$discount->items()->create([
    'condition' => DiscountCondition::Eligibility,
    'discountable_type' => User::class,
    'discountable_id' => $userId,
]);

Zone

// Get discount zone (market)
$discount->zone; // Zone model or null

// Restrict discount to a zone
$discount->update(['zone_id' => $zoneId]);

Value Handling

Fixed amount values are stored in cents. Percentage values are stored as the percentage number. For a $10 fixed discount, store 1000 (cents). For a 15% percentage discount, store 15:

Discount::query()->create([
    'code' => 'SAVE10',
    'type' => DiscountType::FixedAmount,
    'value' => 1000, // 1000 cents = $10.00
]);

Discount::query()->create([
    'code' => 'SAVE15',
    'type' => DiscountType::Percentage,
    'value' => 15, // 15%
]);

Usage Limit Enforcement

Discounts can cap the total number of redemptions with usage_limit and restrict each customer to one redemption with usage_limit_per_user. Both limits are enforced with strong consistency guarantees so that a coupon can never be silently over-redeemed under concurrent checkout.

Global Usage Limit

The usage_limit column caps the total number of redemptions across all customers. The total_use counter is incremented atomically inside the CreateOrderFromCartAction transaction:

The discount row is locked with lockForUpdate to serialize concurrent checkouts.
A conditional UPDATE increments total_use only if it is still below usage_limit.
If the conditional update affects zero rows, the limit was exhausted between cart validation and commit. DiscountLimitReachedException::global() is thrown and the order transaction rolls back, so no order is created.

This compare-and-swap pattern is what fixes the silent over-redemption issue that was patched in v2.8.

Per-User Limit

When usage_limit_per_user is true, each customer can redeem the discount at most once. The check counts prior orders on the orders.discount_id column (introduced in v2.8), not the legacy DiscountDetail.total_use counter:

use Shopper\Models\Order;

Order::query()
    ->where('discount_id', $discount->id)
    ->where('customer_id', $cart->customer_id)
    ->exists();

The same query runs in two places. DiscountValidator rejects the code at cart-apply time so the customer is not surprised at checkout. CreateOrderFromCartAction re-checks at commit and throws DiscountLimitReachedException::perUser() if the customer redeemed it between cart apply and commit.

Helpers

$discount->hasReachedLimit();

if ($discount->usage_limit !== null) {
    $remaining = $discount->usage_limit - $discount->total_use;
}

Handling DiscountLimitReachedException

Wrap your checkout flow to surface a friendly message to the customer when either limit is hit at commit time:

use Shopper\Cart\Actions\CreateOrderFromCartAction;
use Shopper\Cart\Exceptions\DiscountLimitReachedException;

try {
    $order = resolve(CreateOrderFromCartAction::class)->execute($cart);
} catch (DiscountLimitReachedException $e) {
    return back()->with('error', 'This discount can no longer be used.');
}

The exception has two static constructors that match the two limit types:

Constructor	Thrown When
`DiscountLimitReachedException::global($code)`	Global `usage_limit` was reached between cart validation and order commit
`DiscountLimitReachedException::perUser($code)`	Customer already redeemed a discount with `usage_limit_per_user` set

Creating Discounts

Percentage Discount for All Orders

use Shopper\Core\Models\Discount;
use Shopper\Core\Enum\DiscountType;
use Shopper\Core\Enum\DiscountApplyTo;
use Shopper\Core\Enum\DiscountEligibility;
use Shopper\Core\Enum\DiscountRequirement;

$discount = Discount::query()->create([
    'code' => 'SUMMER20',
    'type' => DiscountType::Percentage,
    'value' => 20, // 20% off
    'is_active' => true,
    'apply_to' => DiscountApplyTo::Order,
    'eligibility' => DiscountEligibility::Everyone,
    'min_required' => DiscountRequirement::None,
    'start_at' => now(),
    'end_at' => now()->addMonth(),
]);

Fixed Amount Discount with Minimum Order

$discount = Discount::query()->create([
    'code' => 'SAVE10',
    'type' => DiscountType::FixedAmount,
    'value' => 1000, // 1000 cents = $10 off
    'is_active' => true,
    'apply_to' => DiscountApplyTo::Order,
    'eligibility' => DiscountEligibility::Everyone,
    'min_required' => DiscountRequirement::Price,
    'min_required_value' => '5000', // Minimum 5000 cents = $50 order
    'start_at' => now(),
    'usage_limit' => 100, // Max 100 uses
]);

Product-Specific Discount

$discount = Discount::query()->create([
    'code' => 'PRODUCT15',
    'type' => DiscountType::Percentage,
    'value' => 15,
    'is_active' => true,
    'apply_to' => DiscountApplyTo::Products,
    'eligibility' => DiscountEligibility::Everyone,
    'min_required' => DiscountRequirement::None,
    'start_at' => now(),
]);

// Link specific products
$discount->items()->createMany([
    [
        'condition' => 'apply_to',
        'discountable_type' => Product::class,
        'discountable_id' => $product1->id,
    ],
    [
        'condition' => 'apply_to',
        'discountable_type' => Product::class,
        'discountable_id' => $product2->id,
    ],
]);

VIP Customer Discount

$discount = Discount::query()->create([
    'code' => 'VIP30',
    'type' => DiscountType::Percentage,
    'value' => 30,
    'is_active' => true,
    'apply_to' => DiscountApplyTo::Order,
    'eligibility' => DiscountEligibility::Customers,
    'min_required' => DiscountRequirement::None,
    'start_at' => now(),
    'usage_limit_per_user' => true, // One use per customer
]);

// Link eligible customers
foreach ($vipCustomers as $customer) {
    $discount->items()->create([
        'condition' => 'eligibility',
        'discountable_type' => User::class,
        'discountable_id' => $customer->id,
    ]);
}

Retrieving Discounts

use Shopper\Core\Models\Discount;

// Get all active discounts
$discounts = Discount::query()
    ->where('is_active', true)
    ->where('start_at', '<=', now())
    ->where(function ($q) {
        $q->whereNull('end_at')
            ->orWhere('end_at', '>', now());
    })
    ->get();

// Get discount by code
$discount = Discount::query()
    ->where('code', 'SUMMER20')
    ->where('is_active', true)
    ->first();

// Get discounts for a zone
$discounts = Discount::query()
    ->where('is_active', true)
    ->where(function ($q) use ($zoneId) {
        $q->whereNull('zone_id')
            ->orWhere('zone_id', $zoneId);
    })
    ->get();

// Get discounts with available uses
$discounts = Discount::query()
    ->where('is_active', true)
    ->where(function ($q) {
        $q->whereNull('usage_limit')
            ->orWhereColumn('total_use', '<', 'usage_limit');
    })
    ->get();

Discount Validation

When a coupon is applied to a cart via CartManager::applyCoupon(), the Cart package validates the discount automatically during the calculation pipeline. You do not need to build manual validation logic. The built-in DiscountValidator checks all rules (active status, date range, usage limits, eligibility, zone, minimum amounts) and produces clear error messages. For cases outside the cart pipeline where you need to check a discount programmatically:

use Shopper\Core\Models\Discount;

$discount = Discount::query()
    ->where('code', $code)
    ->where('is_active', true)
    ->first();

if ($discount && ! $discount->hasReachedLimit()) {
    // Discount is valid and has remaining uses
}

Configuration

Disabling Discounts

If your store doesn’t use discount codes, disable the feature in config/shopper/features.php:

use Shopper\Enum\FeatureState;

return [
    'discount' => FeatureState::Disabled,
];

Permissions

The admin panel generates five permissions for discount management:

Permission	Description
`browse_discounts`	View the discounts list
`read_discounts`	View a single discount
`add_discounts`	Create new discounts
`edit_discounts`	Edit existing discounts
`delete_discounts`	Delete discounts

Components

To customize the admin UI for discount management:

php artisan shopper:component:publish discount

Creates config/shopper/components/discount.php:

use Shopper\Livewire;

return [
    'pages' => [
        'discount-index' => Livewire\Pages\Discount\Index::class,
    ],
    'components' => [
        'slide-overs.discount-form' => Livewire\SlideOvers\DiscountForm::class,
    ],
];

Storefront Example

Applying a discount code on the storefront uses the Cart package API. The CartManager::applyCoupon() method validates the code exists, and the calculation pipeline handles the rest (validation rules, discount calculation, and adjustment creation):

namespace App\Http\Controllers;

use Illuminate\Http\Request;
use Shopper\Cart\CartManager;
use Shopper\Cart\Exceptions\InvalidDiscountException;
use Shopper\Cart\Facades\Cart;

class CouponController extends Controller
{
    public function apply(Request $request)
    {
        $request->validate(['code' => 'required|string']);

        $manager = resolve(CartManager::class);

        try {
            $manager->applyCoupon(Cart::current(), $request->code);
        } catch (InvalidDiscountException $e) {
            return back()->with('error', 'Invalid discount code.');
        }

        return back()->with('success', 'Discount applied.');
    }

    public function remove()
    {
        resolve(CartManager::class)->removeCoupon(Cart::current());

        return back()->with('success', 'Discount removed.');
    }
}

Use Cases

Scenario	Type	Apply To	Eligibility	Requirement
Site-wide sale	Percentage	Order	Everyone	None
Free shipping over $50	Fixed	Order	Everyone	Price
Buy 3+ get 10% off	Percentage	Order	Everyone	Quantity
VIP member exclusive	Percentage	Order	Customers	None
Product clearance	Percentage	Products	Everyone	None
First order discount	Fixed	Order	Customers	None

​Models

​Database Schema

​Discount Table

​Discountable Table (Pivot)

​Discount Type

​Discount Application

​Discount Eligibility

​Discount Requirements

​Discount Condition

​Relationships

​Items (DiscountDetail)

​Zone

​Value Handling

​Usage Limit Enforcement

​Global Usage Limit

​Per-User Limit

​Helpers

​Handling DiscountLimitReachedException

​Creating Discounts

​Percentage Discount for All Orders

​Fixed Amount Discount with Minimum Order

​Product-Specific Discount

​VIP Customer Discount

​Retrieving Discounts

​Discount Validation

​Configuration

​Disabling Discounts

​Permissions

​Components

​Storefront Example

​Use Cases