README

Framework independent cart abstraction library.

Installation

Install the package through composer by running composer require endrilala/cart.

Otherwise just include the endrilala\Cart folder in your project and require 'endrilala/Cart/autoload.php'

Usage

Upon creation the cart class accepts a CartPersistentInterface which will supply the persistence mechanisms to the storage of your choice. Included are Array(most frequently used on $_SESSION superglobal) and File storages.

To add new storage types(such as database) implement a the needed interface and hook the new class into your data.

// Basic usage where we store the cart in the $_SESSION variable
$cart = new Cart(new ArrayPersistenceStrategy($_SESSION, 'cart_data'));

Adding items

$data = ['name' => 'T Shirt', 'color' => 'red'];
$item = new CartItem($identifier = 'PRODUCT_CODE', $price = 10, $quantity = 1, $data);
$item->setVatIncluded(true);
$item->setVatRate(20);

$cart->add($cartItem);
$cart->save();

Updating items

In order to update an item simply fetch it via $cart->get and then adjust the properties as needed.

try {
    $item = $cart->get($rowId);
    $item->setPrice(15);
    
    $cart->save();
} catch(ItemNotFoundException $e) {
    // handle appropriately
}

Deleting

Deleting items is as easy as calling $cart->delete with the appropriate rowId.

Clearing the whole cart

The method $cart->clear deletes all items on the cart.

Summary

Cart summary is available via the getSummary method which provides method like getGrossPrice, getVat, and getNetPrice.

CartItem

This is the class that represents an item in the cart. It's constructor accepts different parameters concerning the behaviour of an item.

Below is an example item creation:

$item = new CartItem(
    $pricePerUnit = 10,
    $quantity = 2,
    $vatRate = 20,
    // denotes whether the vat is included in the pricePerUnit supplied
    $vatIncluded = true
);

Price information

After creating a CartItem instance, all the price details are available via the getPriceInfo method which returns the following details: netPrice, netPricePerUnit, vat, vatPerUnit, grossPrice and grossPricePerUnit.

Fees/Discounts

Discounts are supported via the cartFees property. It contains a collection of CartFee. These can be either flat values, percentages, discounts or as additional fees on the cart total.

// Flat discount
$cart->getCartFees()->add(new CartFee('15 EUR Discount', -15));

// Percent value
$cart->getCartFees()->add(new CartFee('2% Discount', '-2%'));

Processing and or other fees that increase the total of the cart should be added as cart items to better handle the different VAT rates each individual fee may have.