Provide initial state

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

3 files changed, 81 insertions, 0 deletions

diff --git a/lib/private/InitialStateService.php b/lib/private/InitialStateService.php
new file mode 100644
index 00000000000..df7f94fbda1
--- /dev/null
+++ b/lib/private/InitialStateService.php
@@ -0,0 +1,74 @@
+<?php
+declare(strict_types=1);
+/**
+ * @copyright Copyright (c) 2019, Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OC;
+
+use OCP\IInitialStateService;
+use OCP\ILogger;
+
+class InitialStateService implements IInitialStateService {
+
+	/** @var ILogger */
+	private $logger;
+
+	/** @var array */
+	private $states = [];
+
+	/** @var array */
+	private $lazyStates = [];
+
+	public function __construct(ILogger $logger) {
+		$this->logger = $logger;
+	}
+
+	public function provideInitialState(string $appName, $data) {
+		// Scalars and JsonSerializable are fine
+		if (is_scalar($data) || $data instanceof \JsonSerializable || is_array($data)) {
+			$this->states[$appName] = json_encode($data);
+			return;
+		}
+
+		$this->logger->warning('Invalid data provided to provideInitialState by ' . $appName);
+	}
+
+	public function provideLazyInitialState(string $appName, \Closure $closure) {
+		$this->lazyStates[$appName] = $closure;
+	}
+
+	public function getInitialStates(): array {
+		$states = $this->states;
+		foreach ($this->lazyStates as $app => $lazyState) {
+			$state = $lazyState();
+
+			if (!($lazyState instanceof \JsonSerializable)) {
+				$this->logger->warning($app . ' provided an invalid lazy state');
+			}
+
+			$states[$app] = json_encode($state);
+		}
+
+		return $states;
+	}
+
+}
diff --git a/lib/private/Server.php b/lib/private/Server.php
index a20676e5271..86d304af5ef 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -144,6 +144,7 @@ use OCP\GlobalScale\IConfig;
 use OCP\Group\ISubAdmin;
 use OCP\ICacheFactory;
 use OCP\IDBConnection;
+use OCP\IInitialStateService;
 use OCP\IL10N;
 use OCP\IServerContainer;
 use OCP\ITempManager;
@@ -1204,6 +1205,8 @@ class Server extends ServerContainer implements IServerContainer {
 
 		$this->registerAlias(ISubAdmin::class, SubAdmin::class);
 
+		$this->registerAlias(IInitialStateService::class, InitialStateService::class);
+
 		$this->connectDispatcher();
 	}
 
diff --git a/lib/private/TemplateLayout.php b/lib/private/TemplateLayout.php
index 284f14c5db4..e4a2724de67 100644
--- a/lib/private/TemplateLayout.php
+++ b/lib/private/TemplateLayout.php
@@ -220,6 +220,10 @@ class TemplateLayout extends \OC_Template {
 
 			}
 		}
+
+		/** @var InitialStateService $initialState */
+		$initialState = \OC::$server->query(InitialStateService::class);
+		$this->assign('initialStates', $initialState->getInitialStates());
 	}
 
 	/**