add logger docs

developer_manual/app/logging.rst

@@ -1,4 +1,79 @@
+=======
 Logging
 =======
 
-.. sectionauthor:: Bernhard Posselt <dev@bernhard-posselt.com>
+.. sectionauthor:: Bernhard Posselt <dev@bernhard-posselt.com>
+
+The logger can be injected from the ServerContainer:
+
+
+.. code-block:: php
+
+    <?php
+    namespace OCA\MyApp\AppInfo;
+
+    use \OCP\AppFramework\App;
+
+    use \OCA\MyApp\Service\AuthorService;
+
+
+    class Application extends App {
+
+        public function __construct(array $urlParams=array()){
+            parent::__construct('myapp', $urlParams);
+
+            $container = $this->getContainer();
+
+            /**
+             * Controllers
+             */
+            $container->registerService('AuthorService', function($c) {
+                return new AuthorService(
+                    $c->query('Logger'),
+                    $c->query('AppName')
+                );
+            });
+
+            $container->registerService('Logger', function($c) {
+                return $c->query('ServerContainer')->getLogger();
+            });
+        }
+    }
+
+and then be used in the following way:
+
+.. code-block:: php
+
+    <?php
+    namespace OCA\MyApp\Service;
+
+    use \OCP\ILogger;
+
+
+    class AuthorService {
+
+        private $logger;
+        private $appName;
+
+        public function __construct(ILogger $logger, $appName){
+            $this->logger = $logger;
+            $this->appName = $appName;
+        }
+
+        public function log($message) {
+            $this->logger->error('hi', array('app' => $this->appName));
+        }
+
+    }
+
+
+The following methods are available:
+
+* **emergency**
+* **alert**
+* **critical**
+* **error**
+* **warning**
+* **notice**
+* **info**
+* **debug**