Fixes #6844: `yii\base\ArrayableTrait::toArray()` now allows recursive `$fields` and `$expand`

framework/CHANGELOG.md

@@ -36,6 +36,7 @@ Yii Framework 2 Change Log
 - Enh #3087: Added `yii\helpers\BaseHtml::error()` "errorSource" option to be able to customize errors display (yanggs07, developeruz, silverfire)
 - Enh #3250: Added support for events partial wildcard matching (klimov-paul)
 - Enh #5515: Added default value for `yii\behaviors\BlameableBehavior` for cases when the user is guest (dmirogin)
+- Enh #6844: `yii\base\ArrayableTrait::toArray()` now allows recursive `$fields` and `$expand` (bboure)
 - Enh #7988: Added `\yii\helpers\Console::errorSummary()` and `\yii\helpers\Json::errorSummary()` (developeruz)
 - Enh #7996: Short syntax for verb in GroupUrlRule (schojniak, developeruz)
 - Enh #8752: Allow specify `$attributeNames` as a string for `yii\base\Model` `validate()` method (developeruz)
@@ -64,7 +65,6 @@ Yii Framework 2 Change Log
 - Enh: Added check to `yii\base\Model::formName()` to prevent source path disclosure when form is represented by an anonymous class (silverfire)
 - Chg #15420: Handle OPTIONS request in `yii\filter\Cors` so the preflight check isn't passed trough authentication filters (michaelarnauts, leandrogehlen)
 
-
 2.0.13.1 November 14, 2017
 --------------------------
 

framework/base/ArrayableTrait.php

@@ -103,13 +103,19 @@ trait ArrayableTrait
      * This method will first identify which fields to be included in the resulting array by calling [[resolveFields()]].
      * It will then turn the model into an array with these fields. If `$recursive` is true,
      * any embedded objects will also be converted into arrays.
+     * When embeded objects are [[Arrayable]], their respective nested fields will be extracted and passed to [[toArray()]].
      *
      * If the model implements the [[Linkable]] interface, the resulting array will also have a `_link` element
      * which refers to a list of links as specified by the interface.
      *
-     * @param array $fields the fields being requested. If empty, all fields as specified by [[fields()]] will be returned.
+     * @param array $fields the fields being requested.
+     * If empty or if it contains '*', all fields as specified by [[fields()]] will be returned.
+     * Fields can be nested, separated with dots (.). e.g.: item.field.sub-field
+     * `$recursive` must be true for nested fields to be extracted. If `$recursive` is false, only the root fields will be extracted.
      * @param array $expand the additional fields being requested for exporting. Only fields declared in [[extraFields()]]
      * will be considered.
+     * Expand can also be nested, separated with dots (.). e.g.: item.expand1.expand2
+     * `$recursive` must be true for nested expands to be extracted. If `$recursive` is false, only the root expands will be extracted.
      * @param bool $recursive whether to recursively return array representation of embedded objects.
      * @return array the array representation of the object
      */
@@ -117,7 +123,27 @@ trait ArrayableTrait
     {
         $data = [];
         foreach ($this->resolveFields($fields, $expand) as $field => $definition) {
-            $data[$field] = is_string($definition) ? $this->$definition : call_user_func($definition, $this, $field);
+            $attribute = is_string($definition) ? $this->$definition : call_user_func($definition, $this, $field);
+
+            if ($recursive) {
+                $nestedFields = $this->extractFieldsFor($fields, $field);
+                $nestedExpand = $this->extractFieldsFor($expand, $field);
+                if ($attribute instanceof Arrayable) {
+                    $attribute = $attribute->toArray($nestedFields, $nestedExpand);
+                } elseif (is_array($attribute)) {
+                    $attribute = array_map(
+                        function ($item) use ($nestedFields, $nestedExpand) {
+                            if ($item instanceof Arrayable) {
+                                return $item->toArray($nestedFields, $nestedExpand);
+                            } else {
+                                return $item;
+                            }
+                        },
+                        $attribute
+                    );
+                }
+            }
+            $data[$field] = $attribute;
         }
 
         if ($this instanceof Linkable) {
@@ -128,8 +154,56 @@ trait ArrayableTrait
     }
 
     /**
+     * Extracts the root field names from nested fields.
+     * Nested fields are separated with dots (.). e.g: "item.id"
+     * The previous example would extract "item".
+     *
+     * @param array $fields The fields requested for extraction
+     * @return array root fields extracted from the given nested fields
+     * @since 2.0.14
+     */
+    protected function extractRootFields(array $fields)
+    {
+        $result = [];
+
+        foreach ($fields as $field) {
+            $result[] = current(explode(".", $field, 2));
+        }
+
+        if (in_array('*', $result, true)) {
+            $result = [];
+        }
+
+        return array_unique($result);
+    }
+
+    /**
+     * Extract nested fields from a fields collection for a given root field
+     * Nested fields are separated with dots (.). e.g: "item.id"
+     * The previous example would extract "id".
+     *
+     * @param array $fields The fields requested for extraction
+     * @param string $rootField The root field for which we want to extract the nested fields
+     * @return array nested fields extracted for the given field
+     * @since 2.0.14
+     */
+    protected function extractFieldsFor(array $fields, $rootField)
+    {
+        $result = [];
+
+        foreach ($fields as $field) {
+            if (0 === strpos($field, "{$rootField}.")) {
+                $result[] = preg_replace("/^{$rootField}\./i", '', $field);
+            }
+        }
+
+        return array_unique($result);
+    }
+
+    /**
      * Determines which fields can be returned by [[toArray()]].
-     * This method will check the requested fields against those declared in [[fields()]] and [[extraFields()]]
+     * This method will first extract the root fields from the given fields.
+     * Then it will check the requested root fields against those declared in [[fields()]] and [[extraFields()]]
      * to determine which fields can be returned.
      * @param array $fields the fields being requested for exporting
      * @param array $expand the additional fields being requested for exporting
@@ -138,6 +212,8 @@ trait ArrayableTrait
      */
     protected function resolveFields(array $fields, array $expand)
     {
+        $fields = $this->extractRootFields($fields);
+        $expand = $this->extractRootFields($expand);
         $result = [];
 
         foreach ($this->fields() as $field => $definition) {

tests/framework/rest/SerializerTest.php

@@ -112,6 +112,147 @@ class SerializerTest extends TestCase
         ], $serializer->serialize($model));
     }
 
+    public function testNestedExpand()
+    {
+        $serializer = new Serializer();
+        $model = new TestModel();
+        $model->extraField3 = new TestModel2();
+
+        TestModel::$extraFields = ['extraField3'];
+        TestModel2::$extraFields = ['extraField4'];
+
+        \Yii::$app->request->setQueryParams(['expand' => 'extraField3.extraField4']);
+        $this->assertSame([
+            'field1' => 'test',
+            'field2' => 2,
+            'extraField3' => [
+                'field3' => 'test2',
+                'field4' => 8,
+                'extraField4' => 'testExtra2',
+            ],
+        ], $serializer->serialize($model));
+    }
+
+    public function testFields()
+    {
+        $serializer = new Serializer();
+        $model = new TestModel();
+        $model->extraField3 = new TestModel2();
+
+        TestModel::$extraFields = ['extraField3'];
+
+        \Yii::$app->request->setQueryParams([]);
+        $this->assertSame([
+            'field1' => 'test',
+            'field2' => 2,
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(['fields' => '*']);
+        $this->assertSame([
+            'field1' => 'test',
+            'field2' => 2,
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => 'field1,extraField3.field3',
+                'expand' => 'extraField3.extraField4'
+            ]
+        );
+        $this->assertSame([
+            'field1' => 'test',
+            'extraField3' => [
+                'field3' => 'test2',
+                'extraField4' => 'testExtra2',
+            ],
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => 'extraField3.*',
+                'expand' => 'extraField3',
+            ]
+        );
+        $this->assertSame([
+            'extraField3' => [
+                'field3' => 'test2',
+                'field4' => 8,
+            ],
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => 'extraField3.*',
+                'expand' => 'extraField3.extraField4'
+            ]
+        );
+        $this->assertSame([
+            'extraField3' => [
+                'field3' => 'test2',
+                'field4' => 8,
+                'extraField4' => 'testExtra2',
+            ],
+        ], $serializer->serialize($model));
+
+        $model->extraField3 = [
+            new TestModel2(),
+            new TestModel2(),
+        ];
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => 'extraField3.*',
+                'expand' => 'extraField3',
+            ]
+        );
+        $this->assertSame([
+            'extraField3' => [
+                [
+                    'field3' => 'test2',
+                    'field4' => 8,
+                ],
+                [
+                    'field3' => 'test2',
+                    'field4' => 8,
+                ],
+            ],
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => '*,extraField3.*',
+                'expand' => 'extraField3',
+            ]
+        );
+        $this->assertSame([
+            'field1' => 'test',
+            'field2' => 2,
+            'extraField3' => [
+                [
+                    'field3' => 'test2',
+                    'field4' => 8,
+                ],
+                [
+                    'field3' => 'test2',
+                    'field4' => 8,
+                ],
+            ],
+        ], $serializer->serialize($model));
+
+        \Yii::$app->request->setQueryParams(
+            [
+                'fields' => 'extraField3.field3',
+                'expand' => 'extraField3',
+            ]
+        );
+        $this->assertSame([
+            'extraField3' => [
+                ['field3' => 'test2'],
+                ['field3' => 'test2'],
+            ],
+        ], $serializer->serialize($model));
+    }
+
     /**
      * @see https://github.com/yiisoft/yii2/issues/12107
      */
@@ -284,6 +425,27 @@ class TestModel extends Model
     public $field2 = 2;
     public $extraField1 = 'testExtra';
     public $extraField2 = 42;
+    public $extraField3;
+
+    public function fields()
+    {
+        return static::$fields;
+    }
+
+    public function extraFields()
+    {
+        return static::$extraFields;
+    }
+}
+
+class TestModel2 extends Model
+{
+    public static $fields = ['field3', 'field4'];
+    public static $extraFields = [];
+
+    public $field3 = 'test2';
+    public $field4 = 8;
+    public $extraField4 = 'testExtra2';
 
     public function fields()
     {