fix(plugin-manager): surface plugin update validation failures instead of reporting up-to-date

When a plugin update is available, pre_plugin_checks validates it by
re-downloading the update's files and verifying their SHA256/MD5. On any
failure it reverted the cached .plg to the installed version and the check
returned success, so the Plugins page showed "up-to-date" — hiding the
available update entirely.

This is most visible when the root filesystem is full: the (often large) txz
can't be downloaded for the hash check, validation fails, and the update
silently disappears with no error shown to the user.

Record the available version and failure reason in a marker file and render an
"Update validation failed" state (with the reason as a tooltip) in the Plugins
page instead of the silent revert. The marker is cleared once validation
passes or the plugin is updated/installed.

Author: elibosley

emhttp/plugins/dynamix.plugin.manager/include/ShowPlugins.php

@@ -186,8 +186,27 @@
         }
       }
     }
+    // an available update that failed validation: surface it instead of the
+    // silent "up-to-date" the revert would otherwise produce (marker written by
+    // the pre_plugin_checks hook). Common cause: the root filesystem is full so
+    // the update files can't be downloaded for the integrity check.
+    if (!$os && $checked) {
+      $invalid = "/tmp/plugins/".basename($plugin_file).".invalid";
+      if (is_file($invalid)) {
+        $info   = json_decode(file_get_contents($invalid),true) ?: [];
+        $newver = (string)($info['version'] ?? '');
+        if ($newver !== '' && strcmp($newver,$version) > 0) {
+          $reason  = trim((string)($info['reason'] ?? ''));
+          $version .= "<br><span class='red-text'>$newver</span>";
+          $status  = "<span class='warning'".($reason ? " title='".htmlspecialchars($reason,ENT_QUOTES)."'" : "")."><i class='fa fa-exclamation-triangle' aria-hidden='true'></i> "._('Update validation failed')."</span>";
+        } else {
+          @unlink($invalid);
+        }
+      }
+    }
     if (strpos($status,'update')!==false) $rank = '0';
     elseif (strpos($status,'install')!==false) $rank = '1';
+    elseif (strpos($status,'Update validation failed')!==false) $rank = '0';
     elseif ($status=='need check') $rank = '2';
     elseif ($status=='up-to-date') $rank = '3';
     else $rank = '4';

emhttp/plugins/dynamix.plugin.manager/post-hooks/post_plugin_checks

@@ -42,6 +42,8 @@ case 'plugin':
   case 'update':
     // abort if method was unsuccessful
     if ($error) break;
+    // a successful install/update clears any prior validation-failure marker
+    @unlink("/tmp/plugins/$name.invalid");
     // update support link in plugin file
     $info = readJson('/tmp/community.applications/tempFiles/templates.json');
     // find matching support link

emhttp/plugins/dynamix.plugin.manager/pre-hooks/pre_plugin_checks

@@ -39,13 +39,31 @@ case 'plugin':
     // validate plugin update (not applicable to OS updates)
     if (in_array($name, $unraid)) break;
     $new_plugin = "/tmp/plugins/$name";
+    $invalid    = "/tmp/plugins/$name.invalid";
     if (plugin('version', $new_plugin) > plugin('version', $plugin)) {
       echo "Validating $name update\n";
-      if (($status = plugin('validate', $new_plugin)) != 'valid') {
-        echo "$status\n";
+      $new_version = plugin('version', $new_plugin);
+      // scripts/plugin exits non-zero and prints "plugin: <reason>" on failure
+      // (bad hash, or the update files failing to download for the hash check)
+      $output = [];
+      exec("$docroot/plugins/dynamix.plugin.manager/scripts/plugin validate ".escapeshellarg($new_plugin)." 2>&1", $output, $retval);
+      if ($retval != 0) {
+        $reason = trim(preg_replace('/^plugin:\s*/m', '', implode("\n", $output)));
+        echo ($reason ?: 'validation failed')."\n";
+        // An update is available but failed validation. Record why so the webGUI
+        // can surface it, instead of silently reverting to "up-to-date". The most
+        // common cause is the update files not downloading because the root
+        // filesystem is full.
+        file_put_contents($invalid, json_encode(['version'=>$new_version, 'reason'=>$reason]));
         // restore original plugin and undo update
         copy($plugin, $new_plugin);
+      } else {
+        // validation passed - clear any stale failure marker
+        @unlink($invalid);
       }
+    } else {
+      // no newer version available - clear any stale failure marker
+      @unlink($invalid);
     }
     break;
   }