README

This package was written to interact with any PHP application, but I'll demo using CakePHP 3.x to show how to connect to it.

Composer Settings

First we'll want to add the library in via the composer.json file. "cpierce/paypal-wpp": "3.*" will need to be added into your require as follows:

File: composer.json

{
    "name": "cakephp/app",
    "description": "CakePHP skeleton app",
    "homepage": "http://cakephp.org",
    "type": "project",
    "license": "MIT",
    "require": {
        "php": ">=5.5.9",
        "cakephp/cakephp": "~3.3",
        "mobiledetect/mobiledetectlib": "2.*",
        "cakephp/migrations": "~1.0",
        "cakephp/plugin-installer": "*",
        "cpierce/paypal-wpp": "3.*"
    },
    "require-dev": {
        "psy/psysh": "@stable",
        "cakephp/debug_kit": "~3.2",
        "cakephp/bake": "~1.1"
    },
    "suggest": {
        "phpunit/phpunit": "Allows automated tests to be run without system-wide install.",
        "cakephp/cakephp-codesniffer": "Allows to check the code against the coding standards used in CakePHP."
    },
    "autoload": {
        "psr-4": {
            "App\\": "src"
        }
    },
    "autoload-dev": {
        "psr-4": {
            "App\\Test\\": "tests",
            "Cake\\Test\\": "./vendor/cakephp/cakephp/tests"
        }
    },
    "scripts": {
        "post-install-cmd": "App\\Console\\Installer::postInstall",
        "post-autoload-dump": "Cake\\Composer\\Installer\\PluginInstaller::postAutoloadDump"
    },
    "minimum-stability": "stable",
    "prefer-stable": true
}

Once you have this change saved run composer update and let the package download into the vendor app.

General Configuration

To begin you'll need to configure your service username, password and signature. The configuration will need to look something like this:

File: config/bootstrap.php

/**
 * Paypal WPP Payload
 */
Configure::write('PaypalWPP.username', 'username_api1.domain.com');
Configure::write('PaypalWPP.password', '5SWM6YY8YSUY888');
Configure::write('PaypalWPP.signature', 'tlArzO7mr5uXMO6.H2zPIuzAFYn4irhcVyzOPeiUcocJF.H3mGr');

Making a transaction to PayPal WPP

After the configuration is setup you'll want to connect to PayPal WPP using the library.

File: src/Form/SalesForm.php

<?php

namespace App\Form;

use Cake\Form\Form;
use Cake\Form\Schema;
use Cake\Validation\Validator;
use PaypalWPP\PaypalWPP;
use Cake\Core\Configure;

/**
 * Sales Form class.
 *
 * @extends Cake\Form\Form
 */
class SalesForm extends Form
{
    /**
     * Parse Data Array.
     *
     * @var array
     */
    protected $parseData = [];

    /**
     * Build Schema Method.
     *
     * @param Schema $schema
     *
     * @return Schema $schema
     */
    protected function _buildSchema(Schema $schema)
    {
        return $schema->addField('first_name', 'string')
            ->addField('last_email', 'string')
            ->addField('card_number', 'string')
            ->addField('amount', 'string');
    }

    /**
     * Build Validator Method.
     *
     * @param Validator $validator
     *
     * @return Validator $validator
     */
    protected function _buildValidator(Validator $validator)
    {
        return $validator
            ->notBlank('first_name', __('Your first name is required.'))
            ->notBlank('last_name', __('Your last name is required.'))
            ->creditCard('card_number', [
                'amex',
                'visa',
                'disc',
                'mc',
            ], __('Please enter a valid credit card number.'))
            ->notBlank('amount', __('Please enter an amount.'));
    }

    /**
     * Execute Method.
     *
     * @param array $data
     *
     * @return bool
     */
    protected function _execute(array $data)
    {
        $paypal = new PaypalWPP(Configure::read('PaypalWPP'));

        $payment = $paypal->doDirectPayment($data);

        if ($payment['ACK'] == 'Success') {
            $this->parseData = [
                'transaction_id' => $payment['TRANSACTIONID'],
            ];
            return true;
        } else {
            $this->parseData = [
                'failure_message' => $payment['L_LONGMESSAGE0'],
                'failure_short'   => $payment['L_SHORTMESSAGE0'],
            ];
        }

        return false;
    }

    /**
     * Get Parse Data Method.
     *
     * @return string
     */
    public function getParseData()
    {
        return $this->parseData;
    }
}

File: src/Controller/SalesController.php

<?php

namespace App\Controller;

use App\Form\SalesForm;

/**
 * Sales Controller.
 */
class SalesController extends AppController
{
    /**
     * Add Method.
     */
    public function add()
    {
        $sales = new SalesForm();

        if ($this->request->is(['post', 'put'])) {
            $transaction_execute = $sales->execute($this->request->data);
            $transaction = $sales->getParseData();
            if ($transaction_execute) {
                $this->Flash->success(
                    __('Payment Completed Successfully: '.$transaction['transaction_id'])
                );
                $this->render('success');
            } else {
                $this->Flash->error(
                    __('Payment Failed: '.$transaction['failure_message'].'['.$transaction['failure_short'].']')
                );
            }
        }

        $this->set(compact('sales'));
    }
}