Add support for configurable wrapped handlers

README.md

@@ -93,6 +93,8 @@ If some parameters are not present in the constructor, they will be treated as e
     - `class` (optional): classname of the handler you would like to use
     - `formatter` (optional): formatter identifier that you have defined
     - `processors` (optional): array of processor identifiers that you have defined
+    - `handlers` (optional): array of handler identifiers that you have defined
+    - `handler` (optional): single handler identifier that you have defined
 
     Other parameters will be interpreted as constructor parameters for that Handler class and passed in when the handler object is instantiated by the Cascade config loader.<br />
     If some parameters are not present in the constructor, they will be interpreted as extra parameters and Cascade will try to interpret them should they match any custom handler functions that are able to use them. (see [Extra Parameters](#user-content-extra-parameters-other-than-constructors) section below)

src/Config.php

@@ -143,7 +143,7 @@ protected function configureFormatters(array $formatters = array())
     protected function configureHandlers(array $handlers)
     {
         foreach ($handlers as $handlerId => $handlerOptions) {
-            $handlerLoader = new HandlerLoader($handlerOptions, $this->formatters, $this->processors);
+            $handlerLoader = new HandlerLoader($handlerOptions, $this->formatters, $this->processors, $this->handlers);
             $this->handlers[$handlerId] = $handlerLoader->load();
         }
     }

src/Config/Loader/ClassLoader/HandlerLoader.php

@@ -37,14 +37,17 @@ class HandlerLoader extends ClassLoader
      * @param array $handlerOptions Handler options
      * @param Monolog\Formatter\FormatterInterface[] $formatters Array of formatter to pick from
      * @param callable[] $processors Array of processors to pick from
+     * @param callable[] $handlers Array of handlers to pick from
      */
     public function __construct(
         array &$handlerOptions,
         array $formatters = array(),
-        array $processors = array()
+        array $processors = array(),
+        array $handlers = array()
     ) {
         $this->populateFormatters($handlerOptions, $formatters);
         $this->populateProcessors($handlerOptions, $processors);
+        $this->populateHandlers($handlerOptions, $handlers);
         parent::__construct($handlerOptions);
 
         self::initExtraOptionsHandlers();
@@ -109,6 +112,52 @@ private function populateProcessors(array &$handlerOptions, array $processors)
         }
     }
 
+     /**
+     * Replace the handler or handlers in the option array with the corresponding callable(s) from the
+     * array of loaded and callable handlers, if they exist.
+     *
+     * @throws \InvalidArgumentException
+     *
+     * @param  array &$handlerOptions Handler options
+     * @param  callable[] $handlers Array of handlers to pick from
+     */
+    private function populateHandlers(array &$handlerOptions, array $handlers)
+    {
+        $handlerArray = array();
+
+        if (isset($handlerOptions['handlers'])) {
+            foreach ($handlerOptions['handlers'] as $handlerId) {
+                if (isset($handlers[$handlerId])) {
+                    $handlerArray[] = $handlers[$handlerId];
+                } else {
+                    throw new \InvalidArgumentException(
+                        sprintf(
+                            'Cannot add handler "%s" to the handler. Handler not found.',
+                            $handlerId
+                        )
+                    );
+                }
+            }
+
+            $handlerOptions['handlers'] = $handlerArray;
+        }
+
+        if (isset($handlerOptions['handler'])) {
+            $handlerId = $handlerOptions['handler'];
+
+            if (isset($handlers[$handlerId])) {
+                $handlerOptions['handler'] = $handlers[$handlerId];
+            } else {
+                 throw new \InvalidArgumentException(
+                     sprintf(
+                         'Cannot add handler "%s" to the handler. Handler not found.',
+                         $handlerId
+                     )
+                 );
+            }
+        }
+    }
+
     /**
      * Loads the closures as option handlers. Add handlers to this function if
      * you want to support additional custom options.

tests/Config/Loader/ClassLoader/HandlerLoaderTest.php

@@ -218,4 +218,32 @@ public function testHandlerForProcessor()
         $closure = $this->getHandler('*', 'processors');
         $closure($mockHandler, $processorsArray);
     }
+
+    public function testReplacesHandlerNamesInOptionsArrayWithLoadedCallable()
+    {
+        $options = [
+            'handlers' => [
+                'foo',
+                'bar',
+            ],
+            'handler' => 'baz'
+        ];
+        $handlers = [
+            'foo' => function () {
+                return 'foo';
+            },
+            'bar' => function () {
+                return 'bar';
+            },
+            'baz' => function () {
+                return 'baz';
+            },
+        ];
+
+        $loader = new HandlerLoader($options, [], [], $handlers);
+
+        $this->assertSame($handlers['foo'], $options['handlers'][0]);
+        $this->assertSame($handlers['bar'], $options['handlers'][1]);
+        $this->assertSame($handlers['baz'], $options['handler']);
+    }
 }

tests/Fixtures/fixture_config.php

@@ -40,7 +40,20 @@
             'level' => 'ERROR',
             'stream' => './demo_error.log',
             'formatter' => 'spaced'
-        )
+        ),
+
+        'group_handler' => array(
+            'class' => 'Monolog\Handler\GroupHandler',
+            'handlers' => [
+                'console',
+                'info_file_handler',
+            ],
+        ),
+
+        'fingers_crossed_handler' => array(
+            'class' => 'Monolog\Handler\FingersCrossedHandler',
+            'handler' => 'group_handler',
+        ),
     ),
     'processors' => array(
         'tag_processor' => array(