Convert SRU eID script into middleware

Classes/Middleware/SruMiddleware.php

@@ -0,0 +1,183 @@
+<?php
+
+namespace Slub\Dfgviewer\Middleware;
+
+/**
+ *  Copyright notice
+ *
+ *  (c) 2014 Alexander Bigga <[email protected]>
+ *  (c) 2023 Beatrycze Volk <[email protected]>
+ *  All rights reserved
+ *
+ *  This script is part of the TYPO3 project. The TYPO3 project is
+ *  free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  The GNU General Public License can be found at
+ *  http://www.gnu.org/copyleft/gpl.html.
+ *
+ *  This script is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  This copyright notice MUST APPEAR in all copies of the script!
+ */
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use TYPO3\CMS\Core\Http\Response;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Plugin 'DFG-Viewer: SRU Client Middleware for the 'dfgviewer' extension.
+ *
+ * @package TYPO3
+ * @subpackage tx_dfgviewer
+ * @access public
+ */
+class SruMiddleware implements MiddlewareInterface
+{
+
+    /**
+     * The main method of the middleware.
+     *
+     * @access public
+     *
+     * @param ServerRequestInterface $request
+     * @param RequestHandlerInterface $handler
+     *
+     * @return ResponseInterface
+     */
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler) : ResponseInterface
+    {
+        $response = $handler->handle($request);
+        // parameters are sent by POST --> use getParsedBody() instead of getQueryParams()
+        $parameters = $request->getParsedBody();
+        // Return if not this middleware
+        if (!isset($parameters['middleware']) || ($parameters['middleware'] != 'dfgviewer/sru')) {
+            return $response;
+        }
+
+        $sru = (string) $parameters['sru'];
+        $query = (string) $parameters['q'];
+
+        $url = $sru . '?operation=searchRetrieve&version=1.2&startRecord=1&maximumRecords=10&recordSchema=dfg-viewer/page&query=' . urlencode($query);
+
+        // make request to SRU service
+        $sruXML = simplexml_load_file($url);
+
+        $results = [];
+
+        if ($sruXML !== FALSE) {
+            // the result may be a valid <srw:searchRetrieveResponse> or some HTML code
+            $sruResponse = $sruXML->xpath('/srw:searchRetrieveResponse');
+
+            if ($sruResponse === FALSE) {
+                $results['error'] = '';
+            } else {
+                $sruRecords = $sruXML->xpath('/srw:searchRetrieveResponse/srw:records/srw:record');
+                if ($sruRecords === FALSE || empty($sruRecords)) {
+                    $results['error'] = '';
+                } else {
+                    $results = $this->getSruRecords($sruRecords);
+                }
+            }
+        }
+
+        // create response object
+        /** @var Response $response */
+        $response = GeneralUtility::makeInstance(Response::class);
+        $response->getBody()->write(json_encode($results));
+        return $response;
+    }
+
+    /**
+     * Gets parsed SRU records.
+     *
+     * @access private
+     *
+     * @param array $sruRecords records returned by SROU API
+     *
+     * @return array
+     */
+    private function getSruRecords(array $sruRecords): array
+    {
+        $results = [];
+
+        foreach ($sruRecords as $id => $record) {
+            $fullTextHit = $record->xpath('//srw:recordData');
+            $pageAttributes = [];
+            foreach ($fullTextHit[$id]->children('http://dfg-viewer.de/')->page->attributes() as $key => $val) {
+                $pageAttributes[$key] = $val;
+            }
+
+            $hitFound = [];
+            // there may be multiple hits on a page per search query
+            foreach ($fullTextHit[$id]->children('http://dfg-viewer.de/')->page->fulltexthit as $hit) {
+                $hitAttributes = [];
+                foreach ($hit->attributes() as $key => $val) {
+                    $hitAttributes[$key] = $val;
+                }
+
+                $hitFound[] = array('text' => $hit->span, 'attributes' => $hitAttributes);
+            }
+
+            $page = (string) $pageAttributes['id'];
+
+            // get METS file of search hit
+            $parentUrl = (string) $fullTextHit[$id]->children('http://dfg-viewer.de/')->page->parent->attributes()->url;
+
+            // unset $highlightParams but make sure, it's an array()
+            $highlightParams = [];
+
+            // get highlight boxes for all results of a page
+            foreach ($hitFound as $key => $hit) {
+                $highlightField = $hit['attributes']['x1'] . ',' . $hit['attributes']['y1'] . ',' . $hit['attributes']['x2'] . ',' . $hit['attributes']['y2'];
+                if (!in_array($highlightField, $highlightParams)) {
+                    $highlightParams[] = $highlightField;
+                }
+            }
+
+            foreach ($hitFound as $key => $hit) {
+                $spanPreview = '';
+                $spanText = '';
+                if (!empty($hit['attributes']['preview'])) {
+                    $spanPreview = '<span class="sru-preview"><img src="' . $hit['attributes']['preview'] . '"></span>';
+                }
+
+                if (is_object($hit['text'])) {
+                    $spanText = '<span class="sru-textsnippet">';
+                    foreach ($hit['text'] as $key => $text) {
+                        if ($text->attributes()->class[0] == 'highlight') {
+                            $spanText .= '<span class="highlight">' . $text . '</span>';
+                        } else {
+                            $spanText .= $text;
+                        }
+                    }
+                    $spanText .= '</span>';
+                }
+
+                $origImageParams = '0,' . $pageAttributes['width'] . ',' . $pageAttributes['height'];
+
+                $data = [];
+
+                $data['link'] = $parentUrl;
+                $data['page'] = $page;
+                $data['text'] = $spanText;
+                $data['previewImage'] = $spanPreview;
+                $data['previewText'] = $spanText;
+                $data['origImage'] = $origImageParams;
+                $data['highlight'] = urlencode(serialize($highlightParams));
+
+                $results[] = $data;
+            }
+        }
+
+        return $results;
+    }
+}

Configuration/RequestMiddlewares.php

@@ -0,0 +1,35 @@
+<?php
+
+/***************************************************************
+ *  Copyright notice
+ *
+ *  (c) 2023 Beatrycze Volk <[email protected]>
+ *  All rights reserved
+ *
+ *  This script is part of the TYPO3 project. The TYPO3 project is
+ *  free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  The GNU General Public License can be found at
+ *  http://www.gnu.org/copyleft/gpl.html.
+ *
+ *  This script is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  This copyright notice MUST APPEAR in all copies of the script!
+ ***************************************************************/
+
+return [
+    'frontend' => [
+        'dfgviewer/sru' => [
+            'target' => \Kitodo\Dlf\Middleware\SruMiddleware::class,
+            'after' => [
+                'typo3/cms-frontend/prepare-tsfe-rendering'
+            ]
+        ]
+    ],
+];

Resources/Private/JavaScript/dfgviewerSru.js

@@ -35,7 +35,7 @@ $("#tx-dfgviewer-sru-form").submit(function( event ) {
 	$.post(
 		"/",
 		{
-			eID: "tx_dfgviewer_sru_eid",
+			middleware: "dfgviewer/sru",
 			q: $( "input[name='tx_dlf[query]']" ).val(),
 			L: $( "input[name='tx_dfgviewer[L]']" ).val(),
 			id: $( "input[name='tx_dfgviewer[id]']" ).val(),