[FEATURE] General reusable validation implementation and middleware f…

…or validating DOMDocument (#1313)

Co-authored-by: Sebastian Meyer <sebastian.meyer@opencultureconsulting.com>

Build/Test/docker-compose.yml

@@ -1,6 +1,5 @@
 # Adopted/reduced from https://github.com/TYPO3/typo3/blob/608f238a8b7696a49a47e1e73ce8e2845455f0f5/Build/testing-docker/local/docker-compose.yml
 
-version: "2.3"
 services:
   mysql:
     image: docker.io/mysql:${MYSQL_VERSION}

Classes/Middleware/DOMDocumentValidation.php

@@ -0,0 +1,116 @@
+<?php
+
+namespace Kitodo\Dlf\Middleware;
+
+/**
+ * (c) Kitodo. Key to digital objects e.V. <contact@kitodo.org>
+ *
+ * This file is part of the Kitodo and TYPO3 projects.
+ *
+ * @license GNU General Public License version 3 or later.
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+use DOMDocument;
+use InvalidArgumentException;
+use Kitodo\Dlf\Validation\DOMDocumentValidationStack;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use Psr\Log\LoggerAwareTrait;
+use TYPO3\CMS\Core\Http\ResponseFactory;
+use TYPO3\CMS\Core\Log\LogManager;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Extbase\Configuration\ConfigurationManagerInterface;
+use TYPO3\CMS\Extbase\Error\Result;
+
+/**
+ * Middleware for validation of DOMDocuments.
+ *
+ * @package TYPO3
+ * @subpackage dlf
+ * @access public
+ */
+class DOMDocumentValidation implements MiddlewareInterface
+{
+    use LoggerAwareTrait;
+
+    /**
+     * The main method of the middleware.
+     *
+     * @access public
+     *
+     * @param ServerRequestInterface $request for processing
+     * @param RequestHandlerInterface $handler for processing
+     *
+     * @throws InvalidArgumentException
+     *
+     * @return ResponseInterface
+     */
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        $this->logger = GeneralUtility::makeInstance(LogManager::class)->getLogger(static::class);
+        $response = $handler->handle($request);
+        // parameters are sent by POST --> use getParsedBody() instead of getQueryParams()
+        $parameters = $request->getQueryParams();
+
+        // Return if not this middleware
+        if (!isset($parameters['middleware']) || ($parameters['middleware'] != 'dlf/domDocumentValidation')) {
+            return $response;
+        }
+
+        $urlParam = $parameters['url'];
+        if (!isset($urlParam)) {
+            throw new InvalidArgumentException('URL parameter is missing.', 1724334674);
+        }
+
+        /** @var ConfigurationManagerInterface $configurationManager */
+        $configurationManager = GeneralUtility::makeInstance(ConfigurationManagerInterface::class);
+        $settings = $configurationManager->getConfiguration(ConfigurationManagerInterface::CONFIGURATION_TYPE_SETTINGS);
+
+        if (!array_key_exists("domDocumentValidationValidators", $settings)) {
+            $this->logger->error('DOMDocumentValidation is not configured correctly.');
+            throw new InvalidArgumentException('DOMDocumentValidation is not configured correctly.', 1724335601);
+        }
+
+        $validation = GeneralUtility::makeInstance(DOMDocumentValidationStack::class, $settings['domDocumentValidationValidators']);
+
+        if (!GeneralUtility::isValidUrl($urlParam)) {
+            $this->logger->debug('Parameter "' . $urlParam . '" is not a valid url.');
+            throw new InvalidArgumentException('Value of url parameter is not a valid url.', 1724852611);
+        }
+
+        $content = GeneralUtility::getUrl($urlParam);
+        if ($content === false) {
+            $this->logger->debug('Error while loading content of "' . $urlParam . '"');
+            throw new InvalidArgumentException('Error while loading content of url.', 1724420640);
+        }
+
+        $document = new DOMDocument();
+        if ($document->loadXML($content) === false) {
+            $this->logger->debug('Error converting content of "' . $urlParam . '" to xml.');
+            throw new InvalidArgumentException('Error converting content to xml.', 1724420648);
+        }
+
+        $result = $validation->validate($document);
+        return $this->getJsonResponse($result);
+    }
+
+    protected function getJsonResponse(Result $result): ResponseInterface
+    {
+        $resultContent = ["valid" => !$result->hasErrors()];
+
+        foreach ($result->getErrors() as $error) {
+            $resultContent["results"][$error->getTitle()][] = $error->getMessage();
+        }
+
+        /** @var ResponseFactory $responseFactory */
+        $responseFactory = GeneralUtility::makeInstance(ResponseFactory::class);
+        $response = $responseFactory->createResponse()
+            ->withHeader('Content-Type', 'application/json; charset=utf-8');
+        $response->getBody()->write(json_encode($resultContent));
+        return $response;
+    }
+}

Classes/Validation/AbstractDlfValidationStack.php

@@ -0,0 +1,129 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * (c) Kitodo. Key to digital objects e.V. <contact@kitodo.org>
+ *
+ * This file is part of the Kitodo and TYPO3 projects.
+ *
+ * @license GNU General Public License version 3 or later.
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+namespace Kitodo\Dlf\Validation;
+
+use InvalidArgumentException;
+use Psr\Log\LoggerAwareTrait;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Abstract class provides functions for implementing a validation stack.
+ *
+ * @package TYPO3
+ * @subpackage dlf
+ *
+ * @access public
+ */
+abstract class AbstractDlfValidationStack extends AbstractDlfValidator
+{
+    use LoggerAwareTrait;
+
+    const ITEM_KEY_TITLE = "title";
+    const ITEM_KEY_BREAK_ON_ERROR = "breakOnError";
+    const ITEM_KEY_VALIDATOR = "validator";
+
+    protected array $validatorStack = [];
+
+    public function __construct(string $valueClassName)
+    {
+        parent::__construct($valueClassName);
+    }
+
+    /**
+     * Add validators by validation stack configuration to the internal validator stack.
+     *
+     * @param array $configuration The configuration of validators
+     *
+     * @throws InvalidArgumentException
+     *
+     * @return void
+     */
+    public function addValidators(array $configuration): void
+    {
+        foreach ($configuration as $configurationItem) {
+            if (!class_exists($configurationItem["className"])) {
+                $this->logger->error('Unable to load class ' . $configurationItem["className"] . '.');
+                throw new InvalidArgumentException('Unable to load validator class.', 1723200537037);
+            }
+            $breakOnError = !isset($configurationItem["breakOnError"]) || $configurationItem["breakOnError"] !== "false";
+            $this->addValidator($configurationItem["className"], $configurationItem["title"] ?? "", $breakOnError, $configurationItem["configuration"] ?? []);
+        }
+    }
+
+    /**
+     * Add validator to the internal validator stack.
+     *
+     * @param string $className Class name of the validator which was derived from Kitodo\Dlf\Validation\AbstractDlfValidator
+     * @param string $title The title of the validator
+     * @param bool $breakOnError True if the execution of validator stack is interrupted when validator throws an error
+     * @param array|null $configuration The configuration of validator
+     *
+     * @throws InvalidArgumentException
+     *
+     * @return void
+     */
+    protected function addValidator(string $className, string $title, bool $breakOnError = true, array $configuration = null): void
+    {
+        if ($configuration === null) {
+            $validator = GeneralUtility::makeInstance($className);
+        } else {
+            $validator = GeneralUtility::makeInstance($className, $configuration);
+        }
+
+        if (!$validator instanceof AbstractDlfValidator) {
+            $this->logger->error($className . ' must be an instance of AbstractDlfValidator.');
+            throw new InvalidArgumentException('Class must be an instance of AbstractDlfValidator.', 1723121212747);
+        }
+
+        $title = empty($title) ? $className : $title;
+
+        $this->validatorStack[] = [self::ITEM_KEY_TITLE => $title, self::ITEM_KEY_VALIDATOR => $validator, self::ITEM_KEY_BREAK_ON_ERROR => $breakOnError];
+    }
+
+    /**
+     * Check if value is valid across all validation classes of validation stack.
+     *
+     * @param $value The value of defined class name.
+     *
+     * @throws InvalidArgumentException
+     *
+     * @return void
+     */
+    protected function isValid($value): void
+    {
+        if (!$value instanceof $this->valueClassName) {
+            $this->logger->error('Value must be an instance of ' . $this->valueClassName . '.');
+            throw new InvalidArgumentException('Type of value is not valid.', 1723127564821);
+        }
+
+        if (empty($this->validatorStack)) {
+            $this->logger->error('The validation stack has no validator.');
+            throw new InvalidArgumentException('The validation stack has no validator.', 1724662426);
+        }
+
+        foreach ($this->validatorStack as $validationStackItem) {
+            $validator = $validationStackItem[self::ITEM_KEY_VALIDATOR];
+            $result = $validator->validate($value);
+
+            foreach ($result->getErrors() as $error) {
+                $this->addError($error->getMessage(), $error->getCode(), [], $validationStackItem[self::ITEM_KEY_TITLE]);
+            }
+
+            if ($validationStackItem[self::ITEM_KEY_BREAK_ON_ERROR] && $result->hasErrors()) {
+                break;
+            }
+        }
+    }
+}

Classes/Validation/AbstractDlfValidator.php

@@ -0,0 +1,56 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * (c) Kitodo. Key to digital objects e.V. <contact@kitodo.org>
+ *
+ * This file is part of the Kitodo and TYPO3 projects.
+ *
+ * @license GNU General Public License version 3 or later.
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+namespace Kitodo\Dlf\Validation;
+
+use InvalidArgumentException;
+use Psr\Log\LoggerAwareInterface;
+use Psr\Log\LoggerAwareTrait;
+use TYPO3\CMS\Core\Log\LogManager;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Extbase\Validation\Validator\AbstractValidator;
+
+/**
+ * Base Validator provides functionalities for using the derived validator within a validation stack.
+ *
+ * @package TYPO3
+ * @subpackage dlf
+ *
+ * @access public
+ */
+abstract class AbstractDlfValidator extends AbstractValidator
+{
+    use LoggerAwareTrait;
+
+    protected string $valueClassName;
+
+    /**
+     * @param $valueClassName string The class name of the value
+     */
+    public function __construct(string $valueClassName)
+    {
+        parent::__construct();
+        $this->logger = GeneralUtility::makeInstance(LogManager::class)->getLogger(static::class);
+        $this->valueClassName = $valueClassName;
+    }
+
+    public function validate($value)
+    {
+        if (!$value instanceof $this->valueClassName) {
+            $this->logger->debug('Value must be an instance of ' . $this->valueClassName . '.');
+            throw new InvalidArgumentException('Type of value is not valid.', 1723126505626);
+        }
+        return parent::validate($value);
+    }
+}

Classes/Validation/DOMDocumentValidationStack.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * (c) Kitodo. Key to digital objects e.V. <contact@kitodo.org>
+ *
+ * This file is part of the Kitodo and TYPO3 projects.
+ *
+ * @license GNU General Public License version 3 or later.
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+namespace Kitodo\Dlf\Validation;
+
+/**
+ * Implementation of AbstractDlfValidationStack for validating DOMDocument against the configured validators.
+ *
+ * @package TYPO3
+ * @subpackage dlf
+ *
+ * @access public
+ */
+class DOMDocumentValidationStack extends AbstractDlfValidationStack
+{
+    public function __construct(array $configuration)
+    {
+        parent::__construct(\DOMDocument::class);
+        $this->addValidators($configuration);
+    }
+}

Classes/Validation/LibXmlTrait.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kitodo\Dlf\Validation;
+
+/**
+ * (c) Kitodo. Key to digital objects e.V. <contact@kitodo.org>
+ *
+ * This file is part of the Kitodo and TYPO3 projects.
+ *
+ * @license GNU General Public License version 3 or later.
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+trait LibXmlTrait
+{
+    /**
+     * Add the errors from the libxml error buffer as validation error.
+     *
+     * To enable user error handling, you need to use libxml_use_internal_errors(true) beforehand.
+     *
+     * @return void
+     */
+    public function addErrorsOfBuffer(): void
+    {
+        $errors = libxml_get_errors();
+        foreach ($errors as $error) {
+            $this->addError($error->message, $error->code);
+        }
+        libxml_clear_errors();
+    }
+
+    public function enableErrorBuffer(): void
+    {
+        libxml_use_internal_errors(true);
+    }
+
+    public function disableErrorBuffer(): void
+    {
+        libxml_use_internal_errors(false);
+    }
+}