Configure mapper cache key

.github/workflows/run-tests.yml

@@ -12,6 +12,7 @@ jobs:
       matrix:
         php:
           - 8.1
+          - 8.2
 
     steps:
       - name: Checkout code

src/MapperConfig.php

@@ -11,6 +11,17 @@ class MapperConfig
      */
     public bool $allowUninitializedFields = true;
 
+    /**
+     * This configures how the class mapper cache key is generated.
+     * Using a different key type can make sure the mapper does not fail when the class changes, however it can be a bit
+     * slower than other types.
+     * - fqcn: creates a hash based on the namespaced class name but does not check for changes
+     * - md5: creates an md5 hash from the file. This will change if the class changes, but is also slower than fqcn
+     * - modified: creates an md5 hash from the file's modification time.
+     * @phpstan-var 'fqcn'|'md5'|'modified'
+     */
+    public string $classCacheKeySource = 'fqcn';
+
     /**
      * This is the directly where generated mappers will be stored.
      * It is recommended to prune this directory on every deploy to prevent old mappers from being used.

src/Objects/ObjectMapper.php

@@ -9,6 +9,7 @@
 use Jerodev\DataMapper\Types\DataType;
 use Jerodev\DataMapper\Types\DataTypeCollection;
 use Jerodev\DataMapper\Types\DataTypeFactory;
+use ReflectionClass;
 
 class ObjectMapper
 {
@@ -46,6 +47,14 @@ public function map(DataType|string $type, array|string $data): ?object
         }
 
         $functionName = self::MAPPER_FUNCTION_PREFIX . \md5($class);
+        if ($this->mapper->config->classCacheKeySource === 'md5' || $this->mapper->config->classCacheKeySource === 'modified') {
+            $reflection = new ReflectionClass($class);
+            $functionName = match ($this->mapper->config->classCacheKeySource) {
+                'md5' => self::MAPPER_FUNCTION_PREFIX . \md5_file($reflection->getFileName()),
+                'modified' => self::MAPPER_FUNCTION_PREFIX . \md5(\filemtime($reflection->getFileName())),
+            };
+        }
+
         $fileName = $this->mapperDirectory() . \DIRECTORY_SEPARATOR . $functionName . '.php';
         if (! \file_exists($fileName)) {
             \file_put_contents(

tests/Objects/ObjectMapperTest.php

@@ -13,6 +13,58 @@
 
 class ObjectMapperTest extends TestCase
 {
+    /** @test */
+    public function it_should_generate_cache_key_based_on_config(): void
+    {
+        $classname = 'A' . \uniqid();
+        $fqcn = '\Jerodev\DataMapper\Tests\_Mocks\\' . $classname;
+        $filename = __DIR__ . '/../_Mocks/' . $classname . '.php';
+        $classContent = <<<PHP
+            <?php
+
+            namespace Jerodev\DataMapper\Tests\_Mocks;
+
+            final class {$classname}
+            {
+                public int \$id;
+            }
+            PHP;
+
+        \file_put_contents($filename, $classContent);
+
+        $config = new MapperConfig();
+        $config->classMapperDirectory = '{$TMP}/' . $classname;
+
+        $mapper = new Mapper($config);
+        $result = $mapper->map($fqcn, ['id' => '8']);
+        $this->assertSame(8, $result->id);
+
+        // Calling the mapper again should reuse the mapper function
+        $mapper->map($fqcn, ['id' => '10']);
+        $mapper->map($fqcn, ['id' => '11']);
+        $mapper->map($fqcn, ['id' => '0']);
+        $this->assertCount(1, \glob(\sys_get_temp_dir() . '/' . $classname . '/*'));
+
+        // Changing the file content should also not change the mapper function
+        \file_put_contents($filename, \str_replace('final ', '', $classContent));
+        $mapper->map($fqcn, ['id' => 8]);
+        $this->assertCount(1, \glob(\sys_get_temp_dir() . '/' . $classname . '/*'));
+
+        // Changing to md5 cache key should create a new mapper
+        $config->classCacheKeySource = 'md5';
+        $result = $mapper->map($fqcn, ['id' => '65536']);
+        $this->assertSame(65536, $result->id);
+        $this->assertCount(2, \glob(\sys_get_temp_dir() . '/' . $classname . '/*'));
+
+        // Changing the file contents should now also create a new mapper
+        \file_put_contents($filename, \str_replace('class', 'final class', $classContent));
+        $mapper->map($fqcn, ['id' => 8]);
+        $this->assertCount(3, \glob(\sys_get_temp_dir() . '/' . $classname . '/*'));
+
+        // Cleanup afterward
+        \unlink($filename);
+    }
+
     /** @test */
     public function it_should_let_classes_map_themselves(): void
     {