Add configurable input length validation

Api/Data/CustomFieldsInterface.php

@@ -26,6 +26,14 @@ interface CustomFieldsInterface
     const CHECKOUT_GOODS_MARK = 'checkout_goods_mark';
     const CHECKOUT_COMMENT = 'checkout_comment';
 
+    const ATTRIBUTES = [
+        self::CHECKOUT_BUYER_EMAIL,
+        self::CHECKOUT_BUYER_NAME,
+        self::CHECKOUT_COMMENT,
+        self::CHECKOUT_GOODS_MARK,
+        self::CHECKOUT_PURCHASE_ORDER_NO,
+    ];
+
     /**
      * Get checkout buyer name
      *

Helper/Config.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Bodak\CheckoutCustomForm\Helper;
+
+
+use Magento\Framework\App\Config\ScopeConfigInterface;
+use Magento\Framework\Exception\NoSuchEntityException;
+use Magento\Store\Model\ScopeInterface;
+use Magento\Store\Model\StoreManagerInterface;
+use Psr\Log\LoggerInterface;
+
+class Config
+{
+    const LIMIT_NOT_SET = -1;
+
+    /**
+     * @var ScopeConfigInterface
+     */
+    private $config;
+
+    /**
+     * @var StoreManagerInterface
+     */
+    private $storeManager;
+
+    /**
+     * @var LoggerInterface
+     */
+    private $logger;
+
+    /**
+     * Config constructor.
+     *
+     * @param ScopeConfigInterface $config
+     * @param StoreManagerInterface $storeManager
+     * @param LoggerInterface $logger
+     */
+    public function __construct(
+        ScopeConfigInterface $config,
+        StoreManagerInterface $storeManager,
+        LoggerInterface $logger
+    ) {
+        $this->config = $config;
+        $this->storeManager = $storeManager;
+        $this->logger = $logger;
+    }
+
+    /**
+     * @return array
+     */
+    public function getEnabledFields()
+    {
+        return explode(',',
+            $this->config->getValue('bodak/checkout/enabled_fields',
+                ScopeInterface::SCOPE_STORE));
+    }
+
+    /**
+     * @param $attribute
+     *
+     * @return int
+     */
+    public function getAllowedLength($attribute)
+    {
+        $configPath = 'checkout/general/' . $attribute . '_limit';
+        try {
+            $allowedLength = $this->config->getValue($configPath, ScopeInterface::SCOPE_STORES,
+                $this->storeManager->getStore()->getId());
+        } catch (NoSuchEntityException $e) {
+            $this->logger->error('Cannot get allowed length for custom field. Falling back to default scope value.');
+            $this->logger->error($e->getMessage(), ['exception' => $e]);
+            $allowedLength = $this->config->getValue($configPath);
+        }
+
+        return (int)$allowedLength ?: self::LIMIT_NOT_SET;
+    }
+}

Model/Checkout/LayoutProcessor/Plugin.php

@@ -12,9 +12,18 @@
 namespace Bodak\CheckoutCustomForm\Model\Checkout\LayoutProcessor;
 
 use Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface;
+use Bodak\CheckoutCustomForm\Helper\Config;
 
 class Plugin
 {
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * @var array
+     */
     private $fields = [
         [
             'dataScopeName' => CustomFieldsInterface::CHECKOUT_BUYER_NAME,
@@ -28,8 +37,8 @@ class Plugin
             ],
             'config' => [
                 'tooltip' => [
-                    'description' => 'We will send an order confirmation to this email address'
-                ]
+                    'description' => 'We will send an order confirmation to this email address',
+                ],
             ],
         ],
         [
@@ -46,48 +55,45 @@ class Plugin
             'config' => [
                 'cols' => 15,
                 'rows' => 2,
-                'maxlength' => 80,
+                'maxlength' => null,
                 'elementTmpl' => 'Bodak_CheckoutCustomForm/form/element/textarea',
             ],
             'showTitle' => false,
         ],
     ];
 
-    /**
-     * @var \Magento\Framework\App\Config\ScopeConfigInterface
-     */
-    protected $_scopeConfig;
-
     /**
      * LayoutProcessor constructor.
      *
-     * @param \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
+     * @param Config $config
      */
-    public function __construct(\Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig)
+    public function __construct(Config $config)
     {
-        $this->_scopeConfig = $scopeConfig;
+        $this->config = $config;
     }
 
     /**
      * @param \Magento\Checkout\Block\Checkout\LayoutProcessor $subject
      * @param array $jsLayout
      *
-     * @see \Magento\Checkout\Block\Checkout\LayoutProcessor::process
      * @return array
+     * @see \Magento\Checkout\Block\Checkout\LayoutProcessor::process
      */
     public function afterProcess(
         \Magento\Checkout\Block\Checkout\LayoutProcessor $subject,
         array $jsLayout
     ) {
-        $config = explode(',',
-            $this->_scopeConfig->getValue('bodak/checkout/enabled_fields',
-                \Magento\Store\Model\ScopeInterface::SCOPE_STORE));
+        $config = $this->config->getEnabledFields();
+
+        $this->applyLengthLimitToFields();
 
         foreach ($this->fields as $sortOrder => $field) {
-            if ( ! in_array($field['dataScopeName'], $config)) {
+            if (!in_array($field['dataScopeName'], $config)) {
                 continue;
             }
-            if(!isset($field['showTitle'])) $field['showTitle'] = true;
+            if (!isset($field['showTitle'])) {
+                $field['showTitle'] = true;
+            }
 
             $formField = [
                 'component' => 'Magento_Ui/js/form/element/abstract',
@@ -112,10 +118,23 @@ public function afterProcess(
             }
 
             $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
-                ['children']['shippingAddress']['children']['custom-checkout-form-container']
-                ['children']['custom-checkout-form-fieldset']['children'][$field['dataScopeName']] = $formField;
+            ['children']['shippingAddress']['children']['custom-checkout-form-container']
+            ['children']['custom-checkout-form-fieldset']['children'][$field['dataScopeName']] = $formField;
         }
 
         return $jsLayout;
     }
+
+    private function applyLengthLimitToFields()
+    {
+        foreach ($this->fields as $key => $field) {
+            $fieldName = $field['dataScopeName'];
+            $allowedLength = $this->config->getAllowedLength($fieldName);
+            if ($allowedLength === Config::LIMIT_NOT_SET) {
+                continue;
+            }
+            $this->fields[$key]['config']['maxlength'] = $allowedLength;
+            $this->fields[$key]['validation']['max_text_length'] = $allowedLength;
+        }
+    }
 }

Model/CustomFields/Validator.php

@@ -0,0 +1,109 @@
+<?php
+
+namespace Bodak\CheckoutCustomForm\Model\CustomFields;
+
+use Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface;
+use Bodak\CheckoutCustomForm\Helper\Config;
+use Magento\Framework\Validator\AbstractValidator;
+use Zend_Validate_Exception;
+use Zend\Filter\Word\UnderscoreToCamelCase;
+
+
+class Validator extends AbstractValidator
+{
+
+    /**
+     * @var CustomFieldsInterface
+     */
+    private $value;
+
+    /**
+     * @var Config
+     */
+    private $config;
+
+    /**
+     * @var UnderscoreToCamelCase
+     */
+    private $underscoreToCamelCase;
+
+    /**
+     * Validator constructor.
+     *
+     * @param Config $config
+     * @param UnderscoreToCamelCase $underscoreToCamelCase
+     */
+    public function __construct(Config $config, UnderscoreToCamelCase $underscoreToCamelCase)
+    {
+        $this->config = $config;
+        $this->underscoreToCamelCase = $underscoreToCamelCase;
+    }
+
+    /**
+     * Returns true if and only if $value meets the validation requirements
+     *
+     * If $value fails validation, then this method returns false, and
+     * getMessages() will return an array of messages that explain why the
+     * validation failed.
+     *
+     * @param mixed $value
+     *
+     * @return boolean
+     * @throws Zend_Validate_Exception If validation of $value is impossible
+     */
+    public function isValid($value)
+    {
+        $valid = true;
+        if (!($value instanceof CustomFieldsInterface)) {
+            throw new Zend_Validate_Exception('Expected value to be instance of \Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface');
+        }
+
+        $this->setValue($value);
+
+        foreach (CustomFieldsInterface::ATTRIBUTES as $attribute) {
+            if (!$this->lengthIsValid($attribute)) {
+                $valid = false;
+                $this->_addMessages([sprintf('Field %s is to long.', $attribute)]);
+            }
+        }
+
+        return $valid;
+    }
+
+    /**
+     * @param $value
+     */
+    private function setValue($value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * @param $attribute
+     *
+     * @return bool
+     */
+    private function lengthIsValid($attribute)
+    {
+        $allowedLength = $this->config->getAllowedLength($attribute);
+
+        if ($allowedLength === Config::LIMIT_NOT_SET) {
+            return true;
+        }
+
+        $function = $this->convertSnakeToCamelCase('get_' . $attribute);
+        $value = call_user_func([$this->value, $function]);
+
+        return mb_strlen($value) <= $allowedLength;
+    }
+
+    /**
+     * @param $string
+     *
+     * @return string
+     */
+    private function convertSnakeToCamelCase($string)
+    {
+        return $this->underscoreToCamelCase->filter($string);
+    }
+}

Model/CustomFieldsRepository.php

@@ -10,6 +10,8 @@
 
 namespace Bodak\CheckoutCustomForm\Model;
 
+use Bodak\CheckoutCustomForm\Model\CustomFields\Validator;
+use Magento\Framework\Exception\LocalizedException;
 use Magento\Quote\Api\CartRepositoryInterface;
 use Magento\Framework\App\Config\ScopeConfigInterface;
 use Magento\Framework\Exception\NoSuchEntityException;
@@ -47,31 +49,42 @@ class CustomFieldsRepository implements CustomFieldsRepositoryInterface
      */
     protected $customFields;
 
+    /**
+     * @var Validator
+     */
+    private $validator;
+
     /**
      * CustomFieldsRepository constructor.
      *
      * @param CartRepositoryInterface $cartRepository CartRepositoryInterface
-     * @param ScopeConfigInterface    $scopeConfig    ScopeConfigInterface
-     * @param CustomFieldsInterface   $customFields   CustomFieldsInterface
+     * @param ScopeConfigInterface $scopeConfig ScopeConfigInterface
+     * @param CustomFieldsInterface $customFields CustomFieldsInterface
+     * @param Validator $validator
      */
     public function __construct(
         CartRepositoryInterface $cartRepository,
         ScopeConfigInterface $scopeConfig,
-        CustomFieldsInterface $customFields
+        CustomFieldsInterface $customFields,
+        Validator $validator
     ) {
         $this->cartRepository = $cartRepository;
         $this->scopeConfig    = $scopeConfig;
         $this->customFields   = $customFields;
+        $this->validator = $validator;
     }
+
     /**
      * Save checkout custom fields
      *
-     * @param int                                                      $cartId       Cart id
+     * @param int $cartId Cart id
      * @param \Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface $customFields Custom fields
      *
-     * @return \Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface
+     * @return \Bodak\CheckoutCustomForm\Api\Data\CustomFieldsInterface|string
      * @throws CouldNotSaveException
      * @throws NoSuchEntityException
+     * @throws \Zend_Validate_Exception
+     * @throws LocalizedException
      */
     public function saveCustomFields(
         int $cartId,
@@ -82,6 +95,10 @@ public function saveCustomFields(
             throw new NoSuchEntityException(__('Cart %1 is empty', $cartId));
         }
 
+        if (!$this->validator->isValid($customFields)) {
+            throw new LocalizedException(__('Custom fields contain invalid values.'));
+        }
+
         try {
             $cart->setData(
                 CustomFieldsInterface::CHECKOUT_BUYER_NAME,