Use default order from Sort in KeysetPaginator

CHANGELOG.md

@@ -51,6 +51,8 @@
 - Chg #219: Don't check correctness of current page in `PaginatorInterface::isOnLastPage()` method (@vjik)
 - Chg #219: Rename `PaginatorException` to `InvalidPageException` (@vjik)
 - Chg #211, #221: Change PHP constraint in `composer.json` to `8.1 - 8.4` (@vjik)
+- New #223: Add `Sort::getDefaultOrder()` method (@vjik)
+- Enh #223: `KeysetPaginator` now uses default order from `Sort` when no sort is set (@vjik)
 
 ## 1.0.1 January 25, 2023
 

composer.json

@@ -38,7 +38,7 @@
     "require-dev": {
         "maglnet/composer-require-checker": "^4.7.1",
         "phpunit/phpunit": "^10.5.46",
-        "rector/rector": "^2.0.15",
+        "rector/rector": "^2.0.18",
         "roave/infection-static-analysis-plugin": "^1.35",
         "spatie/phpunit-watcher": "^1.24",
         "vimeo/psalm": "^5.26.1 || ^6.10.3"

src/Paginator/KeysetPaginator.php

@@ -19,6 +19,7 @@
 use Yiisoft\Data\Reader\SortableDataInterface;
 
 use function array_reverse;
+use function array_slice;
 use function count;
 use function key;
 use function reset;
@@ -121,10 +122,7 @@ public function __construct(ReadableDataInterface $dataReader)
             throw new InvalidArgumentException('Limited data readers are not supported by keyset pagination.');
         }
 
-        $sort = $dataReader->getSort();
-        $this->assertSort($sort);
-
-        $this->dataReader = $dataReader;
+        $this->dataReader = $this->prepareSortInDataReader($dataReader, $dataReader->getSort());
     }
 
     public function __clone()
@@ -255,10 +253,8 @@ public function isSortable(): bool
 
     public function withSort(?Sort $sort): static
     {
-        $this->assertSort($sort);
-
         $new = clone $this;
-        $new->dataReader = $this->dataReader->withSort($sort);
+        $new->dataReader = $this->prepareSortInDataReader($this->dataReader, $sort);
         return $new;
     }
 
@@ -436,14 +432,26 @@ private function getFieldAndSortingFromSort(Sort $sort): array
         ];
     }
 
-    private function assertSort(?Sort $sort): void
+    /**
+     * @param FilterableDataInterface&LimitableDataInterface&ReadableDataInterface<TKey, TValue>&SortableDataInterface $dataReader
+     * @return FilterableDataInterface&LimitableDataInterface&ReadableDataInterface<TKey, TValue>&SortableDataInterface
+     */
+    private function prepareSortInDataReader(ReadableDataInterface $dataReader, ?Sort $sort): ReadableDataInterface
     {
         if ($sort === null) {
             throw new InvalidArgumentException('Data sorting should be configured to work with keyset pagination.');
         }
 
         if (empty($sort->getOrder())) {
-            throw new InvalidArgumentException('Data should be always sorted to work with keyset pagination.');
+            $defaultOrder = $sort->getDefaultOrder();
+            if (empty($defaultOrder)) {
+                throw new InvalidArgumentException('Data should be always sorted to work with keyset pagination.');
+            }
+            $sort = $sort->withOrder(
+                array_slice($defaultOrder, 0, 1, true)
+            );
         }
+
+        return $dataReader->withSort($sort);
     }
 }

src/Reader/Sort.php

@@ -59,7 +59,7 @@ final class Sort
     private bool $withDefaultSorting = true;
 
     /**
-     * @var array Logical fields to order by in form of [name => direction].
+     * @var array Logical fields to order by in form of `[name => direction]`.
      * @psalm-var TOrder
      */
     private array $currentOrder = [];
@@ -321,4 +321,17 @@ public function hasFieldInConfig(string $name): bool
     {
         return isset($this->config[$name]);
     }
+
+    /**
+     * Get a default order for logical fields.
+     *
+     * @return TOrder
+     */
+    public function getDefaultOrder(): array
+    {
+        return array_map(
+            static fn(array $item) => $item['default'],
+            $this->config
+        );
+    }
 }

tests/Paginator/KeysetPaginatorTest.php

@@ -166,15 +166,41 @@ public function testThrowsExceptionForWithSortNull(): void
         (new KeysetPaginator($dataReader))->withSort(null);
     }
 
-    public function testThrowsExceptionWhenNotSorted(): void
+    public function testDefaultOrderUsage(): void
     {
-        $sort = Sort::only(['id', 'name']);
+        $sort = Sort::only(['name', 'id']);
         $dataReader = (new IterableDataReader(self::getDataSet()))->withSort($sort);
+        $paginator = new KeysetPaginator($dataReader);
 
-        $this->expectException(InvalidArgumentException::class);
-        $this->expectExceptionMessage('Data should be always sorted to work with keyset pagination.');
+        $result = $paginator->read();
 
-        new KeysetPaginator($dataReader);
+        $this->assertSame(
+            self::getDataSet([4, 3, 2, 0, 1]),
+            array_values($this->iterableToArray($result)),
+        );
+    }
+
+    public function testDefaultOrderUsageInPrevious(): void
+    {
+        $sort = Sort::only(['name', 'id']);
+        $data = [
+            ['id' => 2, 'name' => 'A'],
+            ['id' => 1, 'name' => 'A'],
+            ['id' => 3, 'name' => 'B'],
+        ];
+        $dataReader = (new IterableDataReader($data))->withSort($sort);
+        $paginator = (new KeysetPaginator($dataReader))
+            ->withToken(PageToken::previous('B'));
+
+        $result = $paginator->read();
+
+        $this->assertSame(
+            [
+                ['id' => 2, 'name' => 'A'],
+                ['id' => 1, 'name' => 'A'],
+            ],
+            array_values($this->iterableToArray($result)),
+        );
     }
 
     public function testThrowsExceptionForWithSortNotSorted(): void
@@ -185,7 +211,7 @@ public function testThrowsExceptionForWithSortNotSorted(): void
         $this->expectException(InvalidArgumentException::class);
         $this->expectExceptionMessage('Data should be always sorted to work with keyset pagination.');
 
-        (new KeysetPaginator($dataReader))->withSort(Sort::only(['id', 'name']));
+        (new KeysetPaginator($dataReader))->withSort(Sort::only([]));
     }
 
     public function testPageSizeCannotBeLessThanOne(): void