feat(unified-search): Use existing min search length config

This setting existed already for the legacy unified search.
This commit expose that setting to the new front-end, and
also ignore non valid requests in the backend.

We also take the opportunity to register the config in the lexicon.

Signed-off-by: Louis Chemineau <louis@chmn.me>

core/AppInfo/ConfigLexicon.php

@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2025 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OC\Core\AppInfo;
+
+use NCU\Config\Lexicon\ConfigLexiconEntry;
+use NCU\Config\Lexicon\ConfigLexiconStrictness;
+use NCU\Config\Lexicon\IConfigLexicon;
+use NCU\Config\ValueType;
+
+/**
+ * Config Lexicon for core.
+ *
+ * Please Add & Manage your Config Keys in that file and keep the Lexicon up to date!
+ */
+class ConfigLexicon implements IConfigLexicon {
+	public const UNIFIED_SEARCH_MIN_SEARCH_LENGTH = 'unified_search_min_search_length';
+
+	public function getStrictness(): ConfigLexiconStrictness {
+		return ConfigLexiconStrictness::IGNORE;
+	}
+
+	public function getAppConfigs(): array {
+		return [
+			new ConfigLexiconEntry(self::UNIFIED_SEARCH_MIN_SEARCH_LENGTH, ValueType::INT, 1, 'Minimum search length to trigger the request', lazy: false),
+		];
+	}
+
+	public function getUserConfigs(): array {
+		return [
+		];
+	}
+}

core/Application.php

@@ -37,6 +37,9 @@ use OCP\Util;
  * @package OC\Core
  */
 class Application extends App {
+
+	public const APP_ID = 'core';
+
 	public function __construct() {
 		parent::__construct('core');
 

core/Controller/UnifiedSearchController.php

@@ -19,6 +19,7 @@ use OCP\AppFramework\Http\Attribute\NoAdminRequired;
 use OCP\AppFramework\Http\Attribute\NoCSRFRequired;
 use OCP\AppFramework\Http\DataResponse;
 use OCP\AppFramework\OCSController;
+use OCP\IL10N;
 use OCP\IRequest;
 use OCP\IURLGenerator;
 use OCP\IUserSession;
@@ -37,6 +38,7 @@ class UnifiedSearchController extends OCSController {
 		private SearchComposer $composer,
 		private IRouter $router,
 		private IURLGenerator $urlGenerator,
+		private IL10N $l10n,
 	) {
 		parent::__construct('core', $request);
 	}
@@ -101,6 +103,11 @@ class UnifiedSearchController extends OCSController {
 		} catch (UnsupportedFilter|InvalidArgumentException $e) {
 			return new DataResponse($e->getMessage(), Http::STATUS_BAD_REQUEST);
 		}
+
+		if ($filters->count() === 0) {
+			return new DataResponse($this->l10n->t('No valid filters provided'), Http::STATUS_BAD_REQUEST);
+		}
+
 		return new DataResponse(
 			$this->composer->search(
 				$this->userSession->getUser(),

core/src/components/UnifiedSearch/UnifiedSearchModal.vue

@@ -173,6 +173,7 @@ import NcButton from '@nextcloud/vue/dist/Components/NcButton.js'
 import NcEmptyContent from '@nextcloud/vue/dist/Components/NcEmptyContent.js'
 import NcInputField from '@nextcloud/vue/dist/Components/NcInputField.js'
 import NcDialog from '@nextcloud/vue/dist/Components/NcDialog.js'
+import { loadState } from '@nextcloud/initial-state'
 
 import CustomDateRangeModal from './CustomDateRangeModal.vue'
 import FilterChip from './SearchFilterChip.vue'
@@ -271,6 +272,7 @@ export default defineComponent({
 			showDateRangeModal: false,
 			internalIsVisible: this.open,
 			initialized: false,
+			minSearchLength: loadState('unified-search', 'min-search-length', 1),
 		}
 	},
 
@@ -283,6 +285,10 @@ export default defineComponent({
 			return !this.isEmptySearch && this.results.length === 0
 		},
 
+		isSearchQueryTooShort() {
+			return this.searchQuery.length < this.minSearchLength
+		},
+
 		showEmptyContentInfo() {
 			return this.isEmptySearch || this.hasNoResults
 		},
@@ -291,9 +297,16 @@ export default defineComponent({
 			if (this.searching && this.hasNoResults) {
 				return t('core', 'Searching …')
 			}
-			if (this.isEmptySearch) {
-				return t('core', 'Start typing to search')
+
+			if (this.isSearchQueryTooShort) {
+				switch (this.minSearchLength) {
+				case 1:
+					return t('core', 'Start typing to search')
+				default:
+					return t('core', 'Minimum search length is {minSearchLength} characters', { minSearchLength: this.minSearchLength })
+				}
 			}
+
 			return t('core', 'No matching results')
 		},
 
@@ -375,7 +388,7 @@ export default defineComponent({
 			})
 		},
 		find(query: string, providersToSearchOverride = null) {
-			if (query.length === 0) {
+			if (this.isSearchQueryTooShort) {
 				this.results = []
 				this.searching = false
 				return

lib/composer/composer/autoload_classmap.php

@@ -1196,6 +1196,7 @@ return array(
     'OC\\Contacts\\ContactsMenu\\Providers\\EMailProvider' => $baseDir . '/lib/private/Contacts/ContactsMenu/Providers/EMailProvider.php',
     'OC\\Contacts\\ContactsMenu\\Providers\\LocalTimeProvider' => $baseDir . '/lib/private/Contacts/ContactsMenu/Providers/LocalTimeProvider.php',
     'OC\\Contacts\\ContactsMenu\\Providers\\ProfileProvider' => $baseDir . '/lib/private/Contacts/ContactsMenu/Providers/ProfileProvider.php',
+    'OC\\Core\\AppInfo\\ConfigLexicon' => $baseDir . '/core/AppInfo/ConfigLexicon.php',
     'OC\\Core\\Application' => $baseDir . '/core/Application.php',
     'OC\\Core\\BackgroundJobs\\BackgroundCleanupUpdaterBackupsJob' => $baseDir . '/core/BackgroundJobs/BackgroundCleanupUpdaterBackupsJob.php',
     'OC\\Core\\BackgroundJobs\\CheckForUserCertificates' => $baseDir . '/core/BackgroundJobs/CheckForUserCertificates.php',

lib/composer/composer/autoload_static.php

@@ -1245,6 +1245,7 @@ class ComposerStaticInit749170dad3f5e7f9ca158f5a9f04f6a2
         'OC\\Contacts\\ContactsMenu\\Providers\\EMailProvider' => __DIR__ . '/../../..' . '/lib/private/Contacts/ContactsMenu/Providers/EMailProvider.php',
         'OC\\Contacts\\ContactsMenu\\Providers\\LocalTimeProvider' => __DIR__ . '/../../..' . '/lib/private/Contacts/ContactsMenu/Providers/LocalTimeProvider.php',
         'OC\\Contacts\\ContactsMenu\\Providers\\ProfileProvider' => __DIR__ . '/../../..' . '/lib/private/Contacts/ContactsMenu/Providers/ProfileProvider.php',
+        'OC\\Core\\AppInfo\\ConfigLexicon' => __DIR__ . '/../../..' . '/core/AppInfo/ConfigLexicon.php',
         'OC\\Core\\Application' => __DIR__ . '/../../..' . '/core/Application.php',
         'OC\\Core\\BackgroundJobs\\BackgroundCleanupUpdaterBackupsJob' => __DIR__ . '/../../..' . '/core/BackgroundJobs/BackgroundCleanupUpdaterBackupsJob.php',
         'OC\\Core\\BackgroundJobs\\CheckForUserCertificates' => __DIR__ . '/../../..' . '/core/BackgroundJobs/CheckForUserCertificates.php',

lib/private/Search/FilterCollection.php

@@ -40,4 +40,8 @@ class FilterCollection implements IFilterCollection {
 			yield $k => $v;
 		}
 	}
+
+	public function count(): int {
+		return count($this->filters);
+	}
 }

lib/private/Search/SearchComposer.php

@@ -10,6 +10,8 @@ namespace OC\Search;
 
 use InvalidArgumentException;
 use OC\AppFramework\Bootstrap\Coordinator;
+use OC\Core\AppInfo\ConfigLexicon;
+use OC\Core\Application;
 use OC\Core\ResponseDefinitions;
 use OCP\IAppConfig;
 use OCP\IURLGenerator;
@@ -312,6 +314,12 @@ class SearchComposer {
 			throw new UnsupportedFilter($name, $providerId);
 		}
 
+		$minSearchLength = $this->appConfig->getValueInt(Application::APP_ID, ConfigLexicon::UNIFIED_SEARCH_MIN_SEARCH_LENGTH);
+		if ($filterDefinition->name() === 'term' && mb_strlen(trim($value)) < $minSearchLength) {
+			// Ignore term values that are not long enough
+			return null;
+		}
+
 		return FilterFactory::get($filterDefinition->type(), $value);
 	}
 

lib/private/TemplateLayout.php

@@ -10,6 +10,8 @@ namespace OC;
 use bantu\IniGetWrapper\IniGetWrapper;
 use OC\AppFramework\Http\Request;
 use OC\Authentication\Token\IProvider;
+use OC\Core\AppInfo\ConfigLexicon;
+use OC\Core\Application;
 use OC\Files\FilenameValidator;
 use OC\Search\SearchQuery;
 use OC\Template\CSSResourceLocator;
@@ -18,6 +20,7 @@ use OC\Template\JSResourceLocator;
 use OCP\App\IAppManager;
 use OCP\AppFramework\Http\TemplateResponse;
 use OCP\Defaults;
+use OCP\IAppConfig;
 use OCP\IConfig;
 use OCP\IInitialStateService;
 use OCP\INavigationManager;
@@ -41,6 +44,7 @@ class TemplateLayout extends \OC_Template {
 	public static $jsLocator = null;
 
 	private IConfig $config;
+	private IAppConfig $appConfig;
 	private IAppManager $appManager;
 	private InitialStateService $initialState;
 	private INavigationManager $navigationManager;
@@ -51,6 +55,7 @@ class TemplateLayout extends \OC_Template {
 	 */
 	public function __construct($renderAs, $appId = '') {
 		$this->config = \OCP\Server::get(IConfig::class);
+		$this->appConfig = \OCP\Server::get(IAppConfig::class);
 		$this->appManager = \OCP\Server::get(IAppManager::class);
 		$this->initialState = \OCP\Server::get(InitialStateService::class);
 		$this->navigationManager = \OCP\Server::get(INavigationManager::class);
@@ -73,9 +78,9 @@ class TemplateLayout extends \OC_Template {
 			$this->initialState->provideInitialState('core', 'active-app', $this->navigationManager->getActiveEntry());
 			$this->initialState->provideInitialState('core', 'apps', array_values($this->navigationManager->getAll()));
 
+			$this->initialState->provideInitialState('unified-search', 'min-search-length', $this->appConfig->getValueInt(Application::APP_ID, ConfigLexicon::UNIFIED_SEARCH_MIN_SEARCH_LENGTH));
 			if ($this->config->getSystemValueBool('unified_search.enabled', false) || !$this->config->getSystemValueBool('enable_non-accessible_features', true)) {
 				$this->initialState->provideInitialState('unified-search', 'limit-default', (int)$this->config->getAppValue('core', 'unified-search.limit-default', (string)SearchQuery::LIMIT_DEFAULT));
-				$this->initialState->provideInitialState('unified-search', 'min-search-length', (int)$this->config->getAppValue('core', 'unified-search.min-search-length', (string)1));
 				$this->initialState->provideInitialState('unified-search', 'live-search', $this->config->getAppValue('core', 'unified-search.live-search', 'yes') === 'yes');
 				Util::addScript('core', 'legacy-unified-search', 'core');
 			} else {

lib/public/Search/IFilterCollection.php

@@ -36,4 +36,11 @@ interface IFilterCollection extends IteratorAggregate {
 	 * @since 28.0.0
 	 */
 	public function getIterator(): \Traversable;
+
+	/**
+	 * Return the number of filters
+	 *
+	 * @since 31.0.10
+	 */
+	public function count(): int;
 }