Added ability to transform result items (#8)

Co-authored-by: Antanas Kiselis <a.kiselis@paysera.com>

CHANGELOG.md

@@ -4,6 +4,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 1.2.0
+### Added
+- `ConfiguredQuery` provides new methods: `setItemTransformer`, `getItemTransformer`.
+Accepts `callable` type. Receives result item - return value replaces received item in result.
+
+## 1.1.0
+### Added
+- Support for datetime
+
 ## 1.0.0
 ### Fixed
 - support single `group-by` statement in `ResultProvider:findCount` - this enables to properly get count of grouped statements. 

README.md

@@ -97,7 +97,7 @@ Use `ResultProvider` class (service) to provide the result.
 
 To get the result, two arguments are needed:
 - `ConfiguredQuery`. This is wrapper around `QueryBuilder` and has configuration for available ordering fields,
-maximum offset and whether total count should be calculated;
+maximum offset, result item transformation and whether total count should be calculated;
 - `Pager`. This holds parameters provided by the user: offset or after/before cursor, limit and ordering directions.
 
 Generally `ConfiguredQuery` holds internals related to `QueryBuilder` so it's recommended to return this from the
@@ -108,10 +108,10 @@ Generally `ConfiguredQuery` holds internals related to `QueryBuilder` so it's re
 Example usage:
 ```php
 <?php
+use Paysera\Pagination\Entity\Doctrine\ConfiguredQuery;
 use Paysera\Pagination\Service\Doctrine\ResultProvider;
 use Paysera\Pagination\Service\CursorBuilder;
 use Paysera\Pagination\Service\Doctrine\QueryAnalyser;
-use Paysera\Pagination\Entity\Doctrine\ConfiguredQuery;
 use Paysera\Pagination\Entity\OrderingConfiguration;
 use Paysera\Pagination\Entity\Pager;
 use Paysera\Pagination\Entity\OrderingPair;
@@ -139,6 +139,9 @@ $configuredQuery = (new ConfiguredQuery($queryBuilder))
     ->addOrderingConfiguration('my_other_name', new OrderingConfiguration('m.otherField', 'otherField'))
     ->setTotalCountNeeded(true) // total count will be returned only if this is called
     ->setMaximumOffset(100) // you can optionally limit maximum offset
+    ->setItemTransformer(function ($item) {
+        // return transformed item if needed
+    })
 ;
 
 $pager = (new Pager())

src/Entity/Doctrine/ConfiguredQuery.php

@@ -31,6 +31,11 @@ class ConfiguredQuery
      */
     private $maximumOffset;
 
+    /**
+     * @var callable
+     */
+    private $itemTransformer;
+
     public function __construct(QueryBuilder $queryBuilder)
     {
         $this->queryBuilder = $queryBuilder;
@@ -124,4 +129,19 @@ public function getMaximumOffset(): int
 
         return $this->maximumOffset;
     }
+
+    /**
+     * @return callable|null
+     */
+    public function getItemTransformer()
+    {
+        return $this->itemTransformer;
+    }
+
+    public function setItemTransformer(callable $itemTransformer): self
+    {
+        $this->itemTransformer = $itemTransformer;
+
+        return $this;
+    }
 }

src/Service/Doctrine/ResultProvider.php

@@ -34,6 +34,10 @@ public function getResultForQuery(ConfiguredQuery $configuredQuery, Pager $pager
 
         $result = $this->buildResult($analysedQuery, $pager);
 
+        if ($configuredQuery->getItemTransformer() !== null) {
+            $this->transformResultItems($configuredQuery->getItemTransformer(), $result);
+        }
+
         if ($configuredQuery->isTotalCountNeeded()) {
             $totalCount = $this->calculateTotalCount($pager, count($result->getItems()));
             if ($totalCount === null) {
@@ -246,7 +250,6 @@ private function buildResultForZeroLimit(AnalysedQuery $analysedQuery, Pager $ze
             ->setHasPrevious($this->existsBeforeCursor($previousCursor, $analysedQuery))
             ->setHasNext(true)
         ;
-
     }
 
     private function buildResultForTooLargeOffset(AnalysedQuery $analysedQuery): Result
@@ -291,6 +294,7 @@ private function existsBeforeCursor(string $previousCursor, AnalysedQuery $analy
             ->setBefore($previousCursor)
             ->setLimit(1)
         ;
+
         return count($this->findItems($analysedQuery, $nextPager)) > 0;
     }
 
@@ -300,6 +304,7 @@ private function existsAfterCursor(string $nextCursor, AnalysedQuery $analysedQu
             ->setAfter($nextCursor)
             ->setLimit(1)
         ;
+
         return count($this->findItems($analysedQuery, $nextPager)) > 0;
     }
 
@@ -365,7 +370,9 @@ private function getSingleValidGroupByColumn(QueryBuilder $queryBuilder)
 
         if (count($groupByParts) > 1) {
             $groupNames = array_map(
-                function (GroupBy $groupBy) { return $groupBy->getParts()[0]; },
+                function (GroupBy $groupBy) {
+                    return $groupBy->getParts()[0];
+                },
                 $groupByParts
             );
             throw new InvalidGroupByException(implode(', ', $groupNames));
@@ -377,4 +384,14 @@ function (GroupBy $groupBy) { return $groupBy->getParts()[0]; },
 
         return $groupByParts[0]->getParts()[0];
     }
+
+    private function transformResultItems(callable $transform, Result $result)
+    {
+        $transformedItems = [];
+        foreach ($result->getItems() as $item) {
+            $transformedItems[] = $transform($item);
+        }
+
+        $result->setItems($transformedItems);
+    }
 }

tests/Functional/Service/Doctrine/ResultIteratorTest.php

@@ -120,4 +120,28 @@ public function testIterate()
             return $logInfo[0] === 'info';
         }));
     }
+
+    public function testTransformResultItems()
+    {
+        $entityManager = $this->createTestEntityManager();
+        $this->createTestData($entityManager);
+
+        $queryBuilder = $entityManager->createQueryBuilder()
+            ->select('p')
+            ->from('PaginationTest:ParentTestEntity', 'p')
+        ;
+
+        $configuredQuery = new ConfiguredQuery($queryBuilder);
+        $configuredQuery->setItemTransformer(function ($item) {
+            return $item->getName();
+        });
+        $resultArray = iterator_to_array($this->resultIterator->iterate($configuredQuery));
+        list($resultItem) = $resultArray;
+        $this->assertEquals('P9', $resultItem);
+
+        $configuredQuery = new ConfiguredQuery($queryBuilder);
+        $resultArray = iterator_to_array($this->resultIterator->iterate($configuredQuery));
+        list($resultItem) = $resultArray;
+        $this->assertEquals('P9', $resultItem->getName());
+    }
 }