PHP code example of mathiasonea / laravel-rulebook

    
        
<?php
require_once('vendor/autoload.php');

/* Start to develop here. Best regards https://php-download.com/ */

    

mathiasonea / laravel-rulebook example snippets

$decision = $vehiclePricingRulebook->resolveAt(
    subject: $vehicle,
    at: $invoice->issued_at,
    context: $pricingContext,
);

$decision->outcome()->formatted();            // 32.500,00 EUR
class_basename($decision->winningRule());     // AustrianElectricVehiclePrice2026
$decision->winningResult()->reason();         // The 2026 Austrian electric-vehicle price applies.

if ($invoice->issued_at < new DateTimeImmutable('2026-01-01T00:00:00+01:00')) {
    return $this->priceUnder2025Policy($vehicle);
}

if ($invoice->issued_at < new DateTimeImmutable('2027-01-01T00:00:00+01:00')) {
    return $this->priceUnder2026Policy($vehicle);
}

return $this->currentPrice($vehicle);

$decision = $vehiclePricingRulebook->resolveAt(
    subject: $vehicle,
    at: $invoice->issued_at,
    context: $pricingContext,
);

$price = $decision->outcome();
$rule = $decision->winningRule();
$reason = $decision->winningResult()->reason();

namespace App\Pricing;

use App\Models\Vehicle;
use MathiasOnea\Rulebook\Rulebook;

/**
 * @extends Rulebook<Vehicle, VehiclePricingContext, Money>
 */
final class VehiclePricingRulebook extends Rulebook
{
    protected function rules(): array
    {
        return [
            DefaultVehiclePrice::class,
            AustrianVehiclePrice::class,
            AustrianElectricVehiclePrice2025::class,
            AustrianElectricVehiclePrice2026::class,
            AustrianElectricVehiclePrice2027::class,
        ];
    }
}

namespace App\Pricing;

use App\Models\Vehicle;
use MathiasOnea\Rulebook\Inputs\RuleInput;
use MathiasOnea\Rulebook\Results\RuleResult;
use MathiasOnea\Rulebook\Rule;

/**
 * @extends Rule<Vehicle, VehiclePricingContext, Money>
 */
abstract class AustrianElectricVehiclePrice extends Rule
{
    public function priority(): int
    {
        return 100;
    }

    public function evaluate(RuleInput $input): RuleResult
    {
        $vehicle = $input->subject(Vehicle::class);
        $context = $input->context(VehiclePricingContext::class);

        if (! $vehicle->isElectric()) {
            return RuleResult::doesNotApply(
                reason: 'The vehicle is not electric.',
            );
        }

        if ($context->country !== Country::Austria) {
            return RuleResult::doesNotApply(
                reason: 'The pricing country is not Austria.',
            );
        }

        return RuleResult::applies(
            outcome: Money::EUR(
                $this->basePriceInCents()
                - $this->incentiveInCents()
                + ($vehicle->batteryCapacityInKwh * $this->batteryFeePerKwhInCents()),
            ),
            reason: "The {$this->policyYear()} Austrian electric-vehicle price applies.",
        );
    }

    abstract protected function policyYear(): int;

    abstract protected function basePriceInCents(): int;

    abstract protected function incentiveInCents(): int;

    abstract protected function batteryFeePerKwhInCents(): int;
}

use DateTimeImmutable;
use MathiasOnea\Rulebook\Periods\ValidityPeriod;

final class AustrianElectricVehiclePrice2025 extends AustrianElectricVehiclePrice
{
    public function validity(): ValidityPeriod
    {
        return ValidityPeriod::between(
            from: new DateTimeImmutable('2025-01-01T00:00:00+01:00'),
            until: new DateTimeImmutable('2026-01-01T00:00:00+01:00'),
        );
    }

    protected function policyYear(): int { return 2025; }
    protected function basePriceInCents(): int { return 35_000_00; }
    protected function incentiveInCents(): int { return 4_000_00; }
    protected function batteryFeePerKwhInCents(): int { return 0; }
}

final class AustrianElectricVehiclePrice2026 extends AustrianElectricVehiclePrice
{
    public function validity(): ValidityPeriod
    {
        return ValidityPeriod::between(
            from: new DateTimeImmutable('2026-01-01T00:00:00+01:00'),
            until: new DateTimeImmutable('2027-01-01T00:00:00+01:00'),
        );
    }

    protected function policyYear(): int { return 2026; }
    protected function basePriceInCents(): int { return 35_000_00; }
    protected function incentiveInCents(): int { return 2_800_00; }
    protected function batteryFeePerKwhInCents(): int { return 4_00; }
}

final class AustrianElectricVehiclePrice2027 extends AustrianElectricVehiclePrice
{
    public function validity(): ValidityPeriod
    {
        return ValidityPeriod::between(
            from: new DateTimeImmutable('2027-01-01T00:00:00+01:00'),
            until: new DateTimeImmutable('2028-01-01T00:00:00+01:00'),
        );
    }

    protected function policyYear(): int { return 2027; }
    protected function basePriceInCents(): int { return 35_500_00; }
    protected function incentiveInCents(): int { return 1_000_00; }
    protected function batteryFeePerKwhInCents(): int { return 5_00; }
}

$decision = $rulebook->resolveAt(
    subject: new Vehicle(
        electric: true,
        batteryCapacityInKwh: 75,
    ),
    at: new DateTimeImmutable('2026-06-15T10:00:00+02:00'),
    context: new VehiclePricingContext(country: Country::Austria),
);

$decision->winningRule();          // an AustrianElectricVehiclePrice2026 instance
$decision->outcome();              // EUR 32,500.00
$decision->winningResult()->reason();
// "The 2026 Austrian electric-vehicle price applies."

$rulebook->resolveAt($vehicle, new DateTimeImmutable('2025-07-01T00:00:00+02:00'), $context)
    ->winningRule(); // AustrianElectricVehiclePrice2025

$rulebook->resolveAt($vehicle, new DateTimeImmutable('2027-07-01T00:00:00+02:00'), $context)
    ->winningRule(); // AustrianElectricVehiclePrice2027

$decision->outcome();             // Money
$decision->winningRule();         // the selected Rule instance
$decision->winningRuleKey();      // the stable key captured for the winner
$decision->winningResult();       // outcome and mandatory reason
$decision->evaluations();         // every RuleEvaluation
$decision->evaluationFor($key);   // one evaluation by stable rule key
$decision->applicableRules();     // 

$evaluation = $rulebook->evaluateNow($vehicle, $context);

$evaluation->evaluations();
$evaluation->applicableEvaluations();
$evaluation->inapplicableEvaluations();
$evaluation->applicableRules();
$evaluation->inapplicableRules();
$evaluation->shadowedRules();
$evaluation->shadowedEvaluations();
$evaluation->conflictingEvaluations();
$evaluation->evaluationFor($key);
$evaluation->hasWinner();
$evaluation->hasConflict();

$decision = $evaluation->resolve();

use Illuminate\Support\Facades\Log;

try {
    $decision = $rulebook->resolveNow($vehicle, $context);
} catch (AmbiguousRuleMatch $exception) {
    foreach ($exception->evaluation->evaluations() as $ruleEvaluation) {
        Log::warning('Ambiguous rulebook evaluation.', [
            'rule' => $ruleEvaluation->key(),
            'applies' => $ruleEvaluation->isApplicable(),
            'reason' => $ruleEvaluation->result()->reason(),
        ]);
    }
}

public function key(): string
{
    return 'austria.ev-price.2026';
}

return RuleResult::doesNotApply(
    reason: 'The vehicle is not electric.',
    reasonCode: 'vehicle_not_electric',
);

$snapshot = $decision->snapshot(
    normalizeOutcome: static fn (Money $money): array => [
        'currency' => $money->currency,
        'amount_in_cents' => $money->cents,
    ],
);

$record = $snapshot->toArray();
$json = json_encode($snapshot, JSON_THROW_ON_ERROR);

$snapshot = $rulebook->evaluateAt($vehicle, $at, $context)->snapshot();

$snapshot->winningRuleKey();       // string|null
$snapshot->conflictingRuleKeys();  // list<string>
$snapshot->evaluations();          // list<RuleEvaluationSnapshot>

ValidityPeriod::always();
ValidityPeriod::from($startsAt);
ValidityPeriod::until($endsAt);
ValidityPeriod::between(from: $startsAt, until: $endsAt);

/**
 * @extends Rulebook<Subscription, null, BillingTerms>
 */
final class SubscriptionBillingRulebook extends Rulebook
{
    protected function rules(): array
    {
        return [
            StandardSubscriptionBilling::class,
            LegacySubscriptionBilling::class,
        ];
    }
}

$terms = $rulebook->resolveNow($subscription)->outcome();

return RuleResult::applies(
    outcome: null,
    reason: 'No charge is the selected billing outcome.',
);