Refine cache purgring

action.php

@@ -657,12 +657,30 @@ class action_plugin_luxtools extends ActionPlugin
             return;
         }
 
-        $removed = CacheInvalidation::purgeAll();
+        $result = CacheInvalidation::purgeSelected(
-        $message = (string)$this->getLang('cache_invalidate_success');
+            $INPUT->bool('luxtools_purge_pagelinks'),
-        if ($message === '') {
+            $INPUT->bool('luxtools_purge_thumbs')
-            $message = 'DokuWiki cache invalidated.';
+        );
+
+        $parts = [];
+
+        $dokuwikiMsg = (string)$this->getLang('cache_invalidate_success');
+        if ($dokuwikiMsg === '') $dokuwikiMsg = 'DokuWiki cache invalidated.';
+        $parts[] = $dokuwikiMsg . ' (' . $result['dokuwiki'] . ')';
+
+        if ($result['pagelinks'] !== null) {
+            $msg = (string)$this->getLang('cache_purge_pagelinks_success');
+            if ($msg === '') $msg = 'Pagelinks cache purged.';
+            $parts[] = $msg . ' (' . $result['pagelinks'] . ')';
         }
-        msg($message . ' (' . $removed . ')', 1);
+
+        if ($result['thumbs'] !== null) {
+            $msg = (string)$this->getLang('cache_purge_thumbs_success');
+            if ($msg === '') $msg = 'Thumbnail cache purged.';
+            $parts[] = $msg . ' (' . $result['thumbs'] . ')';
+        }
+
+        msg(implode(' ', $parts), 1);
 
         $this->redirectToShow($id);
     }

js/main.js

@@ -115,6 +115,62 @@
     }
   }
 
+  // ============================================================
+  // Purge Cache Dialog
+  // ============================================================
+  function initPurgeCacheDialog() {
+    var $link = jQuery('a.luxtools-invalidate-cache');
+    if ($link.length === 0) return;
+
+    $link.on('click.luxtools', function (e) {
+      e.preventDefault();
+
+      var href = $link.attr('href') || '';
+      var lang = (window.LANG && window.LANG.plugins && window.LANG.plugins.luxtools)
+        ? window.LANG.plugins.luxtools
+        : {};
+
+      var $dialog = jQuery(
+        '<div>' +
+        '<p>' + (lang.cache_purge_dialog_intro || 'The DokuWiki cache will always be purged. Optionally also purge the luxtools-specific caches:') + '</p>' +
+        '<p><label><input type="checkbox" id="luxtools-purge-pagelinks"> <strong>' + (lang.cache_purge_pagelinks_label || 'Pagelinks') + '</strong>' +
+        ' &ndash; ' + (lang.cache_purge_pagelinks_desc || 'Purges the pagelink mapping cache') + '</label></p>' +
+        '<p><label><input type="checkbox" id="luxtools-purge-thumbs"> <strong>' + (lang.cache_purge_thumbs_label || 'Thumbnails') + '</strong>' +
+        ' &ndash; ' + (lang.cache_purge_thumbs_desc || 'Purges all cached image thumbnails') + '</label></p>' +
+        '</div>'
+      );
+
+      $dialog.dialog({
+        title: lang.cache_purge_dialog_title || 'Purge Cache',
+        modal: true,
+        width: 420,
+        buttons: [
+          {
+            text: lang.cache_purge_cancel || 'Cancel',
+            click: function () { $dialog.dialog('close'); }
+          },
+          {
+            text: lang.cache_purge_confirm || 'Purge Cache',
+            click: function () {
+              var url = href;
+              if ($dialog.find('#luxtools-purge-pagelinks').prop('checked')) {
+                url += '&luxtools_purge_pagelinks=1';
+              }
+              if ($dialog.find('#luxtools-purge-thumbs').prop('checked')) {
+                url += '&luxtools_purge_thumbs=1';
+              }
+              $dialog.dialog('close');
+              window.location.href = url;
+            }
+          }
+        ],
+        close: function () {
+          jQuery(this).dialog('destroy').remove();
+        }
+      });
+    });
+  }
+
   // ============================================================
   // Initialize
   // ============================================================
@@ -123,6 +179,7 @@
     if (GalleryThumbnails && GalleryThumbnails.init) GalleryThumbnails.init();
     initChronologicalEventTimes();
     if (CalendarWidget && CalendarWidget.init) CalendarWidget.init();
+    initPurgeCacheDialog();
   }, false);
   document.addEventListener('DOMContentLoaded', function () {
     if (Scratchpads && Scratchpads.init) Scratchpads.init();

lang/de/lang.php

@@ -90,3 +90,13 @@ $lang["cache_invalidate_button_title"] = "Gesamten DokuWiki-Cache leeren";
 $lang["cache_invalidate_success"] = "DokuWiki-Cache invalidiert.";
 $lang["cache_invalidate_denied"] = "Nur Admins dürfen den Cache invalidieren.";
 $lang["cache_invalidate_badtoken"] = "Sicherheits-Token ungültig. Bitte erneut versuchen.";
+$lang["cache_purge_dialog_title"] = "Cache leeren";
+$lang["cache_purge_dialog_intro"] = "Der DokuWiki-Cache wird immer geleert. Optional können auch die luxtools-spezifischen Caches geleert werden (das Neu-Aufbauen dieser Caches ist ressourcenintensiv):";
+$lang["cache_purge_pagelinks_label"] = "Seitenlinks";
+$lang["cache_purge_pagelinks_desc"] = "Leert den Seitenlink-Zuordnungs-Cache (pagelink_cache.json)";
+$lang["cache_purge_thumbs_label"] = "Vorschaubilder";
+$lang["cache_purge_thumbs_desc"] = "Leert alle gecachten Vorschaubilder (thumbs-Ordner)";
+$lang["cache_purge_cancel"] = "Abbrechen";
+$lang["cache_purge_confirm"] = "Cache leeren";
+$lang["cache_purge_pagelinks_success"] = "Seitenlink-Cache geleert.";
+$lang["cache_purge_thumbs_success"] = "Vorschaubild-Cache geleert.";

lang/en/lang.php

@@ -91,3 +91,13 @@ $lang["cache_invalidate_button_title"] = "Purge the entire DokuWiki cache";
 $lang["cache_invalidate_success"] = "DokuWiki cache invalidated.";
 $lang["cache_invalidate_denied"] = "Only admins can invalidate cache.";
 $lang["cache_invalidate_badtoken"] = "Security token mismatch. Please retry.";
+$lang["cache_purge_dialog_title"] = "Purge Cache";
+$lang["cache_purge_dialog_intro"] = "The DokuWiki cache will always be purged. Optionally also purge the luxtools-specific caches (rebuilding these is resource-intensive):";
+$lang["cache_purge_pagelinks_label"] = "Pagelinks";
+$lang["cache_purge_pagelinks_desc"] = "Purges the pagelink mapping cache (pagelink_cache.json)";
+$lang["cache_purge_thumbs_label"] = "Thumbnails";
+$lang["cache_purge_thumbs_desc"] = "Purges all cached image thumbnails (thumbs folder)";
+$lang["cache_purge_cancel"] = "Cancel";
+$lang["cache_purge_confirm"] = "Purge Cache";
+$lang["cache_purge_pagelinks_success"] = "Pagelinks cache purged.";
+$lang["cache_purge_thumbs_success"] = "Thumbnail cache purged.";

src/CacheInvalidation.php

@@ -12,11 +12,12 @@ namespace dokuwiki\plugin\luxtools;
 class CacheInvalidation
 {
     /**
-     * Purge the complete DokuWiki cache directory.
+     * Purge the DokuWiki cache directory, preserving the luxtools subfolder.
      *
-     * This removes all files and subdirectories inside the configured
+     * Removes all files and subdirectories inside $conf['cachedir'] except
-     * cache directory ($conf['cachedir']).  It is equivalent to running
+     * the `luxtools/` subdirectory, which contains plugin-specific caches
-     * `rm -rf data/cache/*` on the server.
+     * (thumbnails, pagelink mapping) that are expensive to rebuild and are
+     * managed separately via {@see purgePagelinks()} and {@see purgeThumbs()}.
      *
      * @return int Number of removed entries.
      */
@@ -29,7 +30,79 @@ class CacheInvalidation
             return 0;
         }
 
-        return self::removeDirectoryEntries($cacheDir);
+        return self::removeDirectoryEntries($cacheDir, ['luxtools']);
+    }
+
+    /**
+     * Purge the luxtools pagelink cache file.
+     *
+     * Deletes {@see PageLink::CACHE_FILE} from the luxtools cache sub-directory
+     * ($conf['cachedir']/luxtools/pagelink_cache.json). The file is rebuilt
+     * automatically on the next page request that needs it.
+     *
+     * @return int 1 if the file was removed, 0 otherwise.
+     */
+    public static function purgePagelinks(): int
+    {
+        global $conf;
+
+        $cacheDir = rtrim((string)($conf['cachedir'] ?? ''), '/');
+        if ($cacheDir === '') {
+            return 0;
+        }
+
+        $file = $cacheDir . '/luxtools/pagelink_cache.json';
+        if (!file_exists($file)) {
+            return 0;
+        }
+
+        return @unlink($file) ? 1 : 0;
+    }
+
+    /**
+     * Purge the luxtools thumbnail cache directory.
+     *
+     * Removes all files and sub-directories inside
+     * $conf['cachedir']/luxtools/thumbs. Thumbnails are regenerated
+     * on demand by file.php.
+     *
+     * @return int Number of removed entries.
+     */
+    public static function purgeThumbs(): int
+    {
+        global $conf;
+
+        $cacheDir = rtrim((string)($conf['cachedir'] ?? ''), '/');
+        if ($cacheDir === '') {
+            return 0;
+        }
+
+        $thumbsDir = $cacheDir . '/luxtools/thumbs';
+        if (!is_dir($thumbsDir)) {
+            return 0;
+        }
+
+        return self::removeDirectoryEntries($thumbsDir);
+    }
+
+    /**
+     * Execute a selective cache purge.
+     *
+     * Always purges the DokuWiki cache (skipping the luxtools subfolder).
+     * Optionally also purges the pagelinks cache and/or the thumbnail cache.
+     *
+     * @param bool $pagelinks Whether to also purge the pagelink cache.
+     * @param bool $thumbs    Whether to also purge the thumbnail cache.
+     * @return array{dokuwiki: int, pagelinks: int|null, thumbs: int|null}
+     *   Removed-entry counts per component; pagelinks/thumbs are null when not purged.
+     */
+    public static function purgeSelected(bool $pagelinks, bool $thumbs): array
+    {
+        return [
+            'dokuwiki'  => self::purgeAll(),
+            'pagelinks' => $pagelinks ? self::purgePagelinks() : null,
+            'thumbs'    => $thumbs    ? self::purgeThumbs()    : null,
+        ];
     }
 
     /**
@@ -37,9 +110,10 @@ class CacheInvalidation
      * without removing the directory itself.
      *
      * @param string   $directory
+     * @param string[] $skip      Entry names (not paths) to leave untouched.
      * @return int Number of removed files/directories.
      */
-    public static function removeDirectoryEntries(string $directory): int
+    public static function removeDirectoryEntries(string $directory, array $skip = []): int
     {
         if ($directory === '' || !is_dir($directory) || !is_readable($directory)) {
             return 0;
@@ -51,6 +125,7 @@ class CacheInvalidation
         $removed = 0;
         foreach ($entries as $entry) {
             if ($entry === '.' || $entry === '..') continue;
+            if ($skip !== [] && in_array($entry, $skip, true)) continue;
 
             $path = $directory . '/' . $entry;
             if (is_dir($path) && !is_link($path)) {