Add DataProviderConverter helper

Author: brucealdridge

src/DataProviderConverter.php

@@ -0,0 +1,58 @@
+<?php
+namespace webtoolsnz\helpers;
+
+use yii\data\ActiveDataProvider;
+use yii\db\ActiveRecord;
+use yii\helpers\ArrayHelper;
+
+/**
+ * Class DataProviderConverter
+ * @package webtoolsnz\helpers
+ */
+class DataProviderConverter
+{
+
+    /**
+     * Convert a DataProvider instance and given columns into an array,
+     * ideal for a CSV export, can reuse GridView columns array
+     * @param ActiveDataProvider $dataProvider
+     * @param array $columns
+     * @return array
+     */
+    public static function convertProviderToArray(ActiveDataProvider $dataProvider, $columns)
+    {
+        $header = [];
+        $data = [];
+        foreach($dataProvider->getModels() as $model) {
+            /* @var ActiveRecord $model */
+            $row = [];
+            foreach($columns as $column) {
+                if (is_string($column)) {
+                    // its an attribute
+                    if ($header !== false) {
+                        $header[] = $model->getAttributeLabel($column);
+                    }
+                    $row[] = ArrayHelper::getValue($model, $column);
+                } else if(is_array($column)) {
+                    if ($header !== false) {
+                        $header[] = isset($column['label']) ? $column['label'] : $model->getAttributeLabel($column['attribute']);
+                    }
+                    $row[] = isset($column['value'])
+                        ? (
+                        is_callable($column['value'])
+                            ? call_user_func($column['value'], $model)
+                            : ArrayHelper::getValue($model, $column['value'])
+                        )
+                        : ArrayHelper::getValue($model, $column['attribute']);
+                }
+            }
+
+            if (is_array($header)) {
+                $data[] = $header;
+                $header = false;
+            }
+            $data[] = $row;
+        }
+        return $data;
+    }
+}