Implementation for feature la-haute-societe#15

README.md

@@ -50,7 +50,14 @@ class Project extends \yii\db\ActiveRecord
             ...
             'saveRelations' => [
                 'class'     => SaveRelationsBehavior::className(),
-                'relations' => ['users', 'company']
+                'relations' => ['users', 'company', 'tags'],
+                'junctionTableColumns' => [
+                    'tags' => function ($model) {
+                        return [
+                            'order' => $model->order
+                        ];
+                    }
+                ]
             ],
         ];
     }
@@ -88,6 +95,14 @@ class Project extends \yii\db\ActiveRecord
     {
         return $this->hasMany(User::className(), ['id' => 'user_id'])->via('ProjectUsers');
     }
+
+    /**
+     * @return ActiveQuery
+     */
+    public function getTags()
+    {
+        return $this->hasMany(Tag::className(), ['id' => 'tag_id'])->viaTable('ProjectTags', ['project_id' => 'id']);
+    }
 
 }
 ```
@@ -129,6 +144,12 @@ Attributes of the related model will be massively assigned using the `load() met
 
 > See the PHPUnit tests for more examples.
 
+Populate additional junction table columns in a many-to-many relation
+---------------------------------------------------------------------
+In a many-to-many relation involving a junction table additional column values can be saved to the junction table for each model.
+See the configuration section for examples.
+
+
 Validation
 ----------
 Every declared related models will be validated prior to be saved. If any validation fails, for each related model attribute in error, an error associated with the named relation will be added to the owner model.

src/SaveRelationsBehavior.php

@@ -22,6 +22,7 @@ class SaveRelationsBehavior extends Behavior
 {
 
     public $relations = [];
+    public $junctionTableColumns = [];
     private $_oldRelationValue = [];
     private $_relationsSaveStarted = false;
     private $_transaction;
@@ -320,7 +321,8 @@ public function afterSave()
                             return implode("-", $model->getPrimaryKey(true));
                         });
                         foreach ($addedPks as $key) {
-                            $model->link($relationName, $actualModels[$key]);
+                            $junctionTableColumns = $this->_getJunctionTableColumns($relationName, $actualModels[$key]);
+                            $model->link($relationName, $actualModels[$key], $junctionTableColumns);
                         }
                     } else { // Has one relation
                         if ($this->_oldRelationValue[$relationName] !== $model->{$relationName}) {
@@ -344,6 +346,33 @@ public function afterSave()
         }
     }
 
+    /**
+     * Return array of columns to save to the junction table for a related model having a many-to-many relation.
+     * @param string $relationName
+     * @param BaseActiveRecord $model
+     * @return array
+     */
+    private function _getJunctionTableColumns($relationName, $model)
+    {
+        $junctionTableColumns = [];
+
+        if (array_key_exists($relationName, $this->junctionTableColumns)) {
+            if (is_callable($this->junctionTableColumns[$relationName])) {
+                $junctionTableColumns = $this->junctionTableColumns[$relationName]($model);
+            } elseif (is_array($this->junctionTableColumns[$relationName])) {
+                $junctionTableColumns = $this->junctionTableColumns[$relationName];
+            }
+
+            if (!is_array($junctionTableColumns)) {
+                throw new RuntimeException(
+                    'Junction table columns definiton must return an array, got '.gettype($junctionTableColumns)
+                );
+            }
+        }
+
+        return $junctionTableColumns;
+    }
+
     /**
      * Compute the difference between two set of records using primary keys "tokens"
      * @param BaseActiveRecord[] $initialRelations