Make Solr instantiation more robust

Classes/Common/DocumentList.php

@@ -565,7 +565,10 @@ class DocumentList implements \ArrayAccess, \Countable, \Iterator, \TYPO3\CMS\Co
         // Get Solr instance.
         if (!$this->solr) {
             // Connect to Solr server.
-            if ($this->solr = Solr::getInstance($this->metadata['options']['core'])) {
+            $solr = Solr::getInstance($this->metadata['options']['core']);
+            if ($solr->ready) {
+                $this->solr = $solr;
+                // Get indexed fields.
                 $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
                     ->getQueryBuilderForTable('tx_dlf_metadata');
 

Classes/Common/Indexer.php

@@ -560,7 +560,9 @@ class Indexer
         // Get Solr instance.
         if (!self::$solr) {
             // Connect to Solr server.
-            if (self::$solr = Solr::getInstance($core)) {
+            $solr = Solr::getInstance($core);
+            if ($solr->ready) {
+                self::$solr = $solr;
                 // Load indexing configuration if needed.
                 if ($pid) {
                     self::loadIndexConf($pid);

Classes/Common/Solr.php

@@ -274,9 +274,11 @@ class Solr
             $core = Helper::getIndexNameFromUid($core, 'tx_dlf_solrcores');
         }
         // Check if core is set or null.
-        if (empty($core) && $core !== null) {
+        if (
+            empty($core)
+            && $core !== null
+        ) {
             Helper::devLog('Invalid core UID or name given for Apache Solr', DEVLOG_SEVERITY_ERROR);
-            return;
         }
         if (!empty($core)) {
             // Check if there is an instance in the registry already.
@@ -291,13 +293,10 @@ class Solr
         // Create new instance...
         $instance = new self($core);
         // ...and save it to registry.
-        if (
-            $instance->ready
-            && !empty($instance->core)
-        ) {
-            self::$registry[$instance->core] = $instance;
-        } else {
+        if (!$instance->ready) {
             Helper::devLog('Could not connect to Apache Solr service', DEVLOG_SEVERITY_ERROR);
+        } elseif (!empty($instance->core)) {
+            self::$registry[$instance->core] = $instance;
         }
         return $instance;
     }
@@ -617,7 +616,7 @@ class Solr
      *
      * @return void
      */
-    protected function __construct($core = null)
+    protected function __construct($core)
     {
         // Get Solr connection parameters from configuration.
         $this->loadSolrConnectionInfo();
@@ -649,17 +648,15 @@ class Solr
         // Check if connection is established.
         $query = $this->service->createCoreAdmin();
         $action = $query->createStatus();
-        if (!empty($core)) {
+        if ($core !== null) {
             $action->setCore($core);
         }
         $query->setAction($action);
         try {
             $response = $this->service->coreAdmin($query);
             if ($response->getWasSuccessful()) {
-                // Instantiation successful!
-                $this->ready = true;
                 // Solr is reachable, but is the core as well?
-                if (!empty($core)) {
+                if ($core !== null) {
                     $result = $response->getStatusResultByCoreName($core);
                     if (
                         $result instanceof \Solarium\QueryType\Server\CoreAdmin\Result\StatusResult
@@ -667,8 +664,13 @@ class Solr
                     ) {
                         // Set core name.
                         $this->core = $core;
+                    } else {
+                        // Core not available.
+                        return;
                     }
                 }
+                // Instantiation successful!
+                $this->ready = true;
             }
         } catch (\Exception $e) {
             // Nothing to do here.

Classes/Hooks/DataHandler.php

@@ -246,7 +246,8 @@ class DataHandler
                             $resArray = $allResults[0];
                             if ($resArray['hidden']) {
                                 // Establish Solr connection.
-                                if ($solr = Solr::getInstance($resArray['core'])) {
+                                $solr = Solr::getInstance($resArray['core']);
+                                if ($solr->ready) {
                                     // Delete Solr document.
                                     $updateQuery = $solr->service->createUpdate();
                                     $updateQuery->addDeleteQuery('uid:' . $id);
@@ -325,7 +326,8 @@ class DataHandler
                     case 'move':
                     case 'delete':
                         // Establish Solr connection.
-                        if ($solr = Solr::getInstance($resArray['core'])) {
+                        $solr = Solr::getInstance($resArray['core']);
+                        if ($solr->ready) {
                             // Delete Solr document.
                             $updateQuery = $solr->service->createUpdate();
                             $updateQuery->addDeleteQuery('uid:' . $id);

Classes/Plugin/Collection.php

@@ -142,6 +142,10 @@ class Collection extends \Kitodo\Dlf\Common\AbstractPlugin
             $this->showSingleCollection(intval($resArray['uid']));
         }
         $solr = Solr::getInstance($this->conf['solrcore']);
+        if (!$solr->ready) {
+            Helper::devLog('Apache Solr not available', DEVLOG_SEVERITY_ERROR);
+            return $content;
+        }
         // We only care about the UID and partOf in the results and want them sorted
         $params['fields'] = 'uid,partof';
         $params['sort'] = ['uid' => 'asc'];

Classes/Plugin/Eid/SearchInDocument.php

@@ -53,10 +53,7 @@ class SearchInDocument
         $core = Helper::decrypt($encrypted, $hashed);
         // Perform Solr query.
         $solr = Solr::getInstance($core);
-        if (
-            $solr->ready
-            && $solr->core === $core
-        ) {
+        if ($solr->ready) {
             $query = $solr->service->createSelect();
             $query->setFields(['id', 'uid', 'page']);
             $query->setQuery('fulltext:(' . Solr::escapeQuery((string) $parameters['q']) . ') AND uid:' . intval($parameters['uid']));

Classes/Plugin/Eid/SearchSuggest.php

@@ -49,10 +49,7 @@ class SearchSuggest
         $core = Helper::decrypt($encrypted, $hashed);
         // Perform Solr query.
         $solr = Solr::getInstance($core);
-        if (
-            $solr->ready
-            && $solr->core === $core
-        ) {
+        if ($solr->ready) {
             $query = $solr->service->createSuggester();
             $query->setCount(10);
             $query->setDictionary('suggest');

Classes/Plugin/OaiPmh.php

@@ -923,6 +923,10 @@ class OaiPmh extends \Kitodo\Dlf\Common\AbstractPlugin
         $solr_query .= ' AND timestamp:[' . $from . ' TO ' . $until . ']';
         $documentSet = [];
         $solr = Solr::getInstance($this->conf['solrcore']);
+        if (!$solr->ready) {
+            Helper::devLog('Apache Solr not available', DEVLOG_SEVERITY_ERROR);
+            return $documentSet;
+        }
         if (intval($this->conf['solr_limit']) > 0) {
             $solr->limit = intval($this->conf['solr_limit']);
         }

class.ext_update.php

@@ -141,7 +141,7 @@ class ext_update
         while ($resArray = $result->fetch()) {
             // Instantiate search object.
             $solr = Solr::getInstance($resArray['index_name']);
-            if ($solr->core !== $resArray['index_name']) {
+            if (!$solr->ready) {
                 return true;
             }
         }