`MongoDbPanel` addition mentioned at CHANGELOG.md and README.md

extensions/mongodb/CHANGELOG.md

@@ -9,6 +9,7 @@ Yii Framework 2 mongodb extension Change Log
 - Enh #3520: Added `unlinkAll()`-method to active record to remove all records of a model relation (NmDimas, samdark, cebe)
 - Enh #3778: Gii generator for Active Record model added (klimov-paul)
 - Enh #3947: Migration support added (klimov-paul)
+- Enh #3855: Enh: Added a debug toolbar panel for MongoDB (klimov-paul)
 - Enh #4048: Added `init` event to `ActiveQuery` classes (qiangxue)
 - Enh #4086: changedAttributes of afterSave Event now contain old values (dizews)
 - Enh #4335: `yii\mongodb\log\MongoDbTarget` log target added (klimov-paul)

extensions/mongodb/README.md

@@ -288,6 +288,32 @@ return [
   is very basic and definitely requires adjustments.
 
 
+Using the MongoDB DebugPanel
+----------------------------
+
+The yii2 MongoDB extensions provides a debug panel that can be integrated with the yii debug module
+and shows the executed MongoDB queries.
+
+Add the following to you application config to enable it (if you already have the debug module
+enabled, it is sufficient to just add the panels configuration):
+
+```php
+    // ...
+    'bootstrap' => ['debug'],
+    'modules' => [
+        'debug' => [
+            'class' => 'yii\\debug\\Module',
+            'panels' => [
+                'mongodb' => [
+                    'class' => 'yii\\mongodb\\debug\\MongoDbPanel',
+                ],
+            ],
+        ],
+    ],
+    // ...
+```
+
+
 Using Migrations
 ----------------