Extending the Laravel package Cashier for creating an customer without a credit card

cashier.php

namespace Acme\V1\Billing;


// BillableInterface.php

use Laravel\Cashier\BillableInterface as CashierInterface;

interface BillableInterface extends CashierInterface {

}


// BillableTrait.php

namespace Acme\V1\Billing;

use Laravel\Cashier\BillableTrait as CashierTrait;

trait BillableTrait {

    use CashierTrait;

    /**
     * Get a new billing gateway instance for the given plan.
     *
     * @param  \Laravel\Cashier\PlanInterface|string|null  $plan
     * @return \Acme\V1\Billing\StripeGateway
     */
    public function subscription($plan = null)
    {
        if ($plan instanceof PlanInterface) $plan = $plan->getStripeId();

        return new StripeGateway($this, $plan);
    }

} 


// PlanInterface.php

namespace Acme\V1\Billing;

use Laravel\Cashier\PlanInterface as CashierPlanInterface;

interface PlanInterface extends CashierPlanInterface {

} 


// StripeGateway.php

namespace Acme\V1\Billing;

use Laravel\Cashier\StripeGateway as CashierStripeGateway;

class StripeGateway extends CashierStripeGateway {

    protected $noCard = false;

    /**
     * Subscribe to the plan for the first time.
     *
     * @param  string  $token
     * @param  array   $properties
     * @param  object|null  $customer
     * @return void
     */
    public function createWithoutCard( $token = null, array $properties = array(), $customer = null )
    {
        $freshCustomer = false;

        if ( ! $customer)
        {
            $customer = $this->createStripeCustomer($token, $properties);

            $freshCustomer = true;
        }
        elseif ( ! is_null($token))
        {
            $this->updateCard($token);
        }

        $this->billable->setStripeSubscription(
            $customer->updateSubscription($this->buildPayload())->id
        );

        $customer = $this->getStripeCustomer($customer->id);

        if ($freshCustomer && $trialEnd = $this->getTrialEndForCustomer($customer))
        {
            $this->billable->setTrialEndDate($trialEnd);
        }

        $this->updateLocalStripeData($customer);
    }

    /**
     * @param null  $token
     * @param array $properties
     * @param null  $customer
     */
    public function updateCardWithoutPlan( $token = null, array $properties = array(), $customer = null )
    {
        $freshCustomer = false;

        if ( ! $customer)
        {
            $customer = $this->createStripeCustomer($token, $properties);

            $freshCustomer = true;
        }
        elseif ( ! is_null($token))
        {
            $this->updateCard($token);
        }

        $customer = $this->getStripeCustomer($customer->id);

        if ($freshCustomer && $trialEnd = $this->getTrialEndForCustomer($customer))
        {
            $this->billable->setTrialEndDate($trialEnd);
        }

        $this->updateLocalStripeData($customer);
    }

    /**
     * Update the local Stripe data in storage.
     *
     * @param  \Stripe_Customer  $customer
     * @param  string|null  $plan
     * @return void
     */
    public function updateLocalStripeData($customer, $plan = null)
    {
        try
        {
            $lastFour = $this->getLastFourCardDigits($customer);
        }

        catch ( \Stripe_InvalidRequestError $exception )
        {
            $lastFour = null;
        }

        $this->billable
            ->setStripeId($customer->id)
            ->setStripePlan($plan ?: $this->plan)
            ->setLastFourCardDigits($lastFour)
            ->setStripeIsActive(true)
            ->setSubscriptionEndDate(null)
            ->saveBillableInstance();
    }

    /**
     * @param int    $amount
     * @param string $description
     * @return bool
     */
    public function charge( $amount, $description = '' )
    {
        $customer = $this->getStripeCustomer();

        \Stripe_Charge::create([
            'amount'      => $amount,
            'currency'    => 'usd',
            'customer'    => $customer->id,
            'description' => $description,
        ]);

        return true;
    }

}