[3.0] Lets mods declare the services they use, and admins withdraw them

Languages/en_US/Admin.php

@@ -740,6 +740,7 @@
 $txt['installed_packages'] = 'Installed Packages';
 $txt['package_file_perms'] = 'File Permissions';
 $txt['package_settings'] = 'Options';
+$txt['package_services'] = 'Service Access';
 $txt['themeadmin_admin_title'] = 'Manage and Install';
 $txt['themeadmin_list_title'] = 'Theme Settings';
 $txt['themeadmin_reset_title'] = 'Member Options';

Languages/en_US/Packages.php

@@ -155,6 +155,21 @@
 
 $txt['package_install_options'] = 'Installation Options';
 $txt['package_install_options_desc'] = 'Set various options for how the package manager installs modifications, including backups and FTP access';
+
+$txt['package_services'] = 'Service Access';
+$txt['package_services_desc'] = 'See which services each installed modification provides and uses, and withdraw that access';
+$txt['package_services_info'] = 'Services are the parts of the forum a modification asks to work with. A modification declares them in its package, you approve them when you install it, and you can withdraw them here without uninstalling anything. This describes what a modification asks for; it does not stop a badly behaved one from reaching the forum in other ways.';
+$txt['package_services_none'] = 'No installed modification provides or uses any service.';
+$txt['package_service_provides'] = 'Provides';
+$txt['package_service_uses'] = 'Uses';
+$txt['package_services_status'] = 'Access';
+$txt['package_services_granted'] = 'Allowed';
+$txt['package_services_revoked'] = 'Withdrawn';
+$txt['package_services_grant'] = 'Allow';
+$txt['package_services_revoke'] = 'Withdraw';
+$txt['package_services_not_registered_revoked'] = 'not available, access withdrawn';
+$txt['package_services_not_registered_taken'] = 'not available, another modification provides this service';
+$txt['package_services_core'] = 'Services provided by SMF';
 $txt['package_install_options_ftp_why'] = 'Using the package manager’s FTP functionality is the easiest way to avoid having to manually chmod the files writable through FTP yourself for the package manager to work.<br>Here you can set the default values for some fields.';
 $txt['package_install_options_ftp_server'] = 'FTP Server';
 $txt['package_install_options_ftp_port'] = 'Port';

Sources/Actions/Admin/ACP.php

@@ -145,6 +145,9 @@ class ACP implements ActionInterface, Routable
 						'options' => [
 							'label' => 'package_settings',
 						],
+						'services' => [
+							'label' => 'package_services',
+						],
 					],
 				],
 				'search' => [

Sources/Infrastructure/PackageServices.php

@@ -0,0 +1,149 @@
+<?php
+
+/**
+ * Simple Machines Forum (SMF)
+ *
+ * @package SMF
+ * @author Simple Machines https://www.simplemachines.org
+ * @copyright 2026 Simple Machines and individual contributors
+ * @license https://www.simplemachines.org/about/smf/license.php BSD
+ *
+ * @version 3.0 Alpha 5-dev
+ */
+
+declare(strict_types=1);
+
+namespace SMF\Infrastructure;
+
+use SMF\Config;
+use SMF\Utils;
+
+/**
+ * What each installed package does with services.
+ *
+ * A package says in its package-info.xml which services it provides and which
+ * it wants to use. That is recorded when the package is installed, so the
+ * answer is a setting rather than a trip through the package files, and the
+ * administrator can take the access away again without uninstalling the mod.
+ */
+class PackageServices
+{
+	/***********************
+	 * Public static methods
+	 ***********************/
+
+	/**
+	 * Gets what every installed package does with services.
+	 *
+	 * @return array Each package's name, the services it provides, the ones it
+	 *    uses, and whether it is allowed to, keyed by package ID.
+	 */
+	public static function all(): array
+	{
+		if (empty(Config::$modSettings['package_services'])) {
+			return [];
+		}
+
+		$manifests = Utils::jsonDecode(Config::$modSettings['package_services'], true);
+
+		return \is_array($manifests) ? $manifests : [];
+	}
+
+	/**
+	 * Gets what one package does with services.
+	 *
+	 * @param string $package_id The package's ID.
+	 * @return array The package's entry, or an empty array if it has none.
+	 */
+	public static function get(string $package_id): array
+	{
+		return self::all()[$package_id] ?? [];
+	}
+
+	/**
+	 * Records what a package does with services.
+	 *
+	 * Access is granted at this point, because this is where the administrator
+	 * installed the package after being shown what it asked for.
+	 *
+	 * @param string $package_id The package's ID.
+	 * @param string $name The package's name, as the admin knows it.
+	 * @param array $provides Service IDs the package registers.
+	 * @param array $uses Service IDs the package wants to use.
+	 */
+	public static function record(string $package_id, string $name, array $provides, array $uses): void
+	{
+		if ($provides === [] && $uses === []) {
+			self::forget($package_id);
+
+			return;
+		}
+
+		$manifests = self::all();
+
+		$manifests[$package_id] = [
+			'name' => $name,
+			'provides' => array_values(array_unique($provides)),
+			'uses' => array_values(array_unique($uses)),
+			'granted' => true,
+		];
+
+		self::save($manifests);
+	}
+
+	/**
+	 * Forgets a package, which is what uninstalling it means here.
+	 *
+	 * @param string $package_id The package's ID.
+	 */
+	public static function forget(string $package_id): void
+	{
+		$manifests = self::all();
+
+		if (!isset($manifests[$package_id])) {
+			return;
+		}
+
+		unset($manifests[$package_id]);
+
+		self::save($manifests);
+	}
+
+	/**
+	 * Allows or refuses a package the services it asked for.
+	 *
+	 * A package that has been refused keeps its entry, so the administrator can
+	 * see what it wanted and can change their mind.
+	 *
+	 * @param string $package_id The package's ID.
+	 * @param bool $granted Whether the package may use services.
+	 */
+	public static function setGranted(string $package_id, bool $granted): void
+	{
+		$manifests = self::all();
+
+		if (!isset($manifests[$package_id])) {
+			return;
+		}
+
+		$manifests[$package_id]['granted'] = $granted;
+
+		self::save($manifests);
+	}
+
+	/*************************
+	 * Internal static methods
+	 *************************/
+
+	/**
+	 * Writes the manifests back to the settings.
+	 *
+	 * @param array $manifests The manifests of every package.
+	 */
+	protected static function save(array $manifests): void
+	{
+		Config::updateModSettings([
+			'package_services' => $manifests === [] ? '' : Utils::jsonEncode($manifests),
+		]);
+	}
+}

Sources/Infrastructure/ServiceAccessException.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * Simple Machines Forum (SMF)
+ *
+ * @package SMF
+ * @author Simple Machines https://www.simplemachines.org
+ * @copyright 2026 Simple Machines and individual contributors
+ * @license https://www.simplemachines.org/about/smf/license.php BSD
+ *
+ * @version 3.0 Alpha 5-dev
+ */
+
+declare(strict_types=1);
+
+namespace SMF\Infrastructure;
+
+use Psr\Container\ContainerExceptionInterface;
+
+/**
+ * Thrown when something asks for a service it has no access to.
+ *
+ * The services a package may use are the ones it declared in its
+ * package-info.xml and the administrator granted when installing it.
+ */
+class ServiceAccessException extends \RuntimeException implements ContainerExceptionInterface {}

Sources/Infrastructure/ServiceNotFoundException.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * Simple Machines Forum (SMF)
+ *
+ * @package SMF
+ * @author Simple Machines https://www.simplemachines.org
+ * @copyright 2026 Simple Machines and individual contributors
+ * @license https://www.simplemachines.org/about/smf/license.php BSD
+ *
+ * @version 3.0 Alpha 5-dev
+ */
+
+declare(strict_types=1);
+
+namespace SMF\Infrastructure;
+
+use Psr\Container\NotFoundExceptionInterface;
+
+/**
+ * Thrown when nothing provides the service that was asked for.
+ *
+ * Either no package provides it, or the one that did has had its access
+ * withdrawn, which looks the same to whoever asked.
+ */
+class ServiceNotFoundException extends \RuntimeException implements NotFoundExceptionInterface {}