Change AbstractAdapter to use iterator instead of array (#371)

Author: mhvis

src/Adapter/AbstractAdapter.php

@@ -38,27 +38,33 @@ final public function getData(DataTableState $state): ResultSetInterface
         $this->prepareQuery($query);
         $propertyMap = $this->getPropertyMap($query);
 
-        $rows = [];
         $transformer = $state->getDataTable()->getTransformer();
         $identifier = $query->getIdentifierPropertyPath();
-        foreach ($this->getResults($query) as $result) {
-            $row = [];
-            if (!empty($identifier)) {
-                $row['DT_RowId'] = $this->accessor->getValue($result, $identifier);
-            }
 
-            /** @var AbstractColumn $column */
-            foreach ($propertyMap as list($column, $mapping)) {
-                $value = ($mapping && $this->accessor->isReadable($result, $mapping)) ? $this->accessor->getValue($result, $mapping) : null;
-                $row[$column->getName()] = $column->transform($value, $result);
-            }
-            if (null !== $transformer) {
-                $row = call_user_func($transformer, $row, $result);
+        $data = (function () use ($query, $identifier, $transformer, $propertyMap) {
+            foreach ($this->getResults($query) as $result) {
+                $row = [];
+                if (!empty($identifier)) {
+                    $row['DT_RowId'] = $this->accessor->getValue($result, $identifier);
+                }
+
+                /** @var AbstractColumn $column */
+                foreach ($propertyMap as list($column, $mapping)) {
+                    $value = ($mapping && $this->accessor->isReadable($result, $mapping)) ? $this->accessor->getValue($result, $mapping) : null;
+                    $row[$column->getName()] = $column->transform($value, $result);
+                }
+                if (null !== $transformer) {
+                    $row = call_user_func($transformer, $row, $result);
+                }
+                yield $row;
             }
-            $rows[] = $row;
+        })();
+
+        if (null === $query->getTotalRows() || null === $query->getFilteredRows()) {
+            throw new \LogicException('Adapter did not set row counts');
         }
 
-        return new ArrayResultSet($rows, $query->getTotalRows(), $query->getFilteredRows());
+        return new ResultSet($data, $query->getTotalRows(), $query->getFilteredRows());
     }
 
     /**

src/Adapter/ArrayAdapter.php

@@ -69,7 +69,7 @@ public function getData(DataTableState $state): ResultSetInterface
         $length = $state->getLength() ?? 0;
         $page = $length > 0 ? array_slice($data, $state->getStart(), $state->getLength()) : $data;
 
-        return new ArrayResultSet($page, count($this->data), count($data));
+        return new ResultSet(new \ArrayIterator($page), count($this->data), count($data));
     }
 
     /**

src/Adapter/ArrayResultSet.php renamed to src/Adapter/ResultSet.php

@@ -13,27 +13,22 @@
 namespace Omines\DataTablesBundle\Adapter;
 
 /**
- * ArrayResultSet.
- *
  * @author Niels Keurentjes <[email protected]>
  *
- * @phpstan-type Row array<string, mixed>
+ * @phpstan-type Row array<(int|string), mixed>
+ *
+ * (Note: when using ArrayAdapter, the Row keys may be integers instead of strings.)
  */
-class ArrayResultSet implements ResultSetInterface
+class ResultSet implements ResultSetInterface
 {
-    /** @var Row[] */
-    private array $data;
-    private int $totalRows;
-    private int $totalFilteredRows;
-
     /**
-     * @param Row[] $data
+     * @param \Iterator<Row> $data
      */
-    public function __construct(array $data, ?int $totalRows = null, ?int $totalFilteredRows = null)
-    {
-        $this->data = $data;
-        $this->totalRows = $totalRows ?? count($data);
-        $this->totalFilteredRows = $totalFilteredRows ?? $this->totalRows;
+    public function __construct(
+        private readonly \Iterator $data,
+        private readonly int $totalRows,
+        private readonly int $totalFilteredRows,
+    ) {
     }
 
     public function getTotalRecords(): int
@@ -48,6 +43,6 @@ public function getTotalDisplayRecords(): int
 
     public function getData(): \Iterator
     {
-        return new \ArrayIterator($this->data);
+        return $this->data;
     }
 }

tests/Unit/Adapter/ORMAdapterTest.php

@@ -41,6 +41,7 @@ public function testCountGroupedDataTable(): void
         /** @var ORMAdapter $adapter */
         $adapter = $datatable->getAdapter();
         $data = $adapter->getData(new DataTableState($datatable));
+        iterator_to_array($data->getData());  // Evaluate the iterator to trigger the exception
     }
 
     public function testORMAdapterQueryEvent(): void