fix(state): restore 422 for empty scalar params

src/Doctrine/Common/Filter/EmptyValueParameterTrait.php

@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Doctrine\Common\Filter;
+
+use ApiPlatform\Metadata\Parameter;
+use Symfony\Component\TypeInfo\Type;
+use Symfony\Component\TypeInfo\Type\CollectionType;
+use Symfony\Component\TypeInfo\TypeIdentifier;
+
+/** @internal */
+trait EmptyValueParameterTrait
+{
+    private function ignoreEmptyValue(Parameter $parameter, mixed &$value): bool
+    {
+        if ('' !== $value && !(\is_array($value) && \in_array('', $value, true))) {
+            return false;
+        }
+
+        $nativeType = $parameter->getNativeType();
+        $isStringLike = static fn (Type $t): bool => $t->isIdentifiedBy(TypeIdentifier::STRING)
+            || ($t instanceof CollectionType && $t->getCollectionValueType()->isIdentifiedBy(TypeIdentifier::STRING));
+
+        if (null === $nativeType || $nativeType->isSatisfiedBy($isStringLike)) {
+            return false;
+        }
+
+        if (\is_array($value)) {
+            $value = array_values(array_filter($value, static fn (mixed $v): bool => '' !== $v));
+
+            return [] === $value;
+        }
+
+        return true;
+    }
+}

src/Doctrine/Odm/Filter/ExactFilter.php

@@ -13,6 +13,7 @@
 
 namespace ApiPlatform\Doctrine\Odm\Filter;
 
+use ApiPlatform\Doctrine\Common\Filter\EmptyValueParameterTrait;
 use ApiPlatform\Doctrine\Common\Filter\ManagerRegistryAwareInterface;
 use ApiPlatform\Doctrine\Common\Filter\ManagerRegistryAwareTrait;
 use ApiPlatform\Doctrine\Common\Filter\OpenApiFilterTrait;
@@ -32,6 +33,7 @@
 final class ExactFilter implements FilterInterface, OpenApiParameterFilterInterface, ManagerRegistryAwareInterface
 {
     use BackwardCompatibleFilterDescriptionTrait;
+    use EmptyValueParameterTrait;
     use ManagerRegistryAwareTrait;
     use NestedPropertyHelperTrait;
     use OpenApiFilterTrait;
@@ -50,6 +52,10 @@ public function apply(Builder $aggregationBuilder, string $resourceClass, ?Opera
             return;
         }
 
+        if ($this->ignoreEmptyValue($parameter, $value)) {
+            return;
+        }
+
         if (null === $parameter->getProperty()) {
             throw new InvalidArgumentException(\sprintf('The filter parameter with key "%s" must specify a property. Please provide the property explicitly.', $parameter->getKey()));
         }

src/Doctrine/Odm/composer.json

@@ -25,7 +25,7 @@
     ],
     "require": {
         "php": ">=8.2",
-        "api-platform/doctrine-common": "^4.4",
+        "api-platform/doctrine-common": "^4.4.5",
         "api-platform/metadata": "^4.4",
         "api-platform/serializer": "^4.4",
         "api-platform/state": "^4.4",

src/Doctrine/Orm/Filter/ExactFilter.php

@@ -13,6 +13,7 @@
 
 namespace ApiPlatform\Doctrine\Orm\Filter;
 
+use ApiPlatform\Doctrine\Common\Filter\EmptyValueParameterTrait;
 use ApiPlatform\Doctrine\Common\Filter\OpenApiFilterTrait;
 use ApiPlatform\Doctrine\Orm\NestedPropertyHelperTrait;
 use ApiPlatform\Doctrine\Orm\Util\QueryNameGeneratorInterface;
@@ -28,6 +29,7 @@
 final class ExactFilter implements FilterInterface, OpenApiParameterFilterInterface
 {
     use BackwardCompatibleFilterDescriptionTrait;
+    use EmptyValueParameterTrait;
     use NestedPropertyHelperTrait;
     use OpenApiFilterTrait;
 
@@ -41,6 +43,10 @@ public function apply(QueryBuilder $queryBuilder, QueryNameGeneratorInterface $q
             return;
         }
 
+        if ($this->ignoreEmptyValue($parameter, $value)) {
+            return;
+        }
+
         if (null === $parameter->getProperty()) {
             throw new InvalidArgumentException(\sprintf('The filter parameter with key "%s" must specify a property. Please provide the property explicitly.', $parameter->getKey()));
         }

src/Doctrine/Orm/composer.json

@@ -24,7 +24,7 @@
     ],
     "require": {
         "php": ">=8.2",
-        "api-platform/doctrine-common": "^4.4",
+        "api-platform/doctrine-common": "^4.4.5",
         "api-platform/metadata": "^4.4",
         "api-platform/serializer": "^4.4",
         "api-platform/state": "^4.4",

src/State/Parameter/ValueCaster.php

@@ -13,12 +13,9 @@
 
 namespace ApiPlatform\State\Parameter;
 
-use ApiPlatform\Metadata\Exception\BadRequestException;
-
 /**
  * Caster returns the value unchanged when it can not be casted, so constraint validation can
- * reject it. An empty string is the exception: it can not represent a scalar native type, so we
- * throw a Bad Request (400) rather than letting it reach the filter as a raw, untyped value.
+ * reject it. Therefore we do not need to throw exceptions, validation will just fail.
  *
  * @internal
  */
@@ -33,7 +30,6 @@ public static function toBool(mixed $v): mixed
         return match (strtolower($v)) {
             '1', 'true' => true,
             '0', 'false' => false,
-            '' => throw new BadRequestException('An empty value cannot be cast to a boolean.'),
             default => $v,
         };
     }
@@ -44,10 +40,6 @@ public static function toInt(mixed $v): mixed
             return $v;
         }
 
-        if ('' === $v) {
-            throw new BadRequestException('An empty value cannot be cast to an integer.');
-        }
-
         $value = filter_var($v, \FILTER_VALIDATE_INT);
 
         return false === $value ? $v : $value;
@@ -59,10 +51,6 @@ public static function toFloat(mixed $v): mixed
             return $v;
         }
 
-        if ('' === $v) {
-            throw new BadRequestException('An empty value cannot be cast to a float.');
-        }
-
         $value = filter_var($v, \FILTER_VALIDATE_FLOAT);
 
         return false === $value ? $v : $value;

src/State/Tests/Parameter/ValueCasterTest.php

@@ -13,7 +13,6 @@
 
 namespace ApiPlatform\State\Tests\Parameter;
 
-use ApiPlatform\Metadata\Exception\BadRequestException;
 use ApiPlatform\State\Parameter\ValueCaster;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
@@ -67,15 +66,10 @@ public static function floatProvider(): \Generator
         yield 'float passthrough' => [1.5, 1.5];
     }
 
-    /**
-     * An empty string cannot represent a scalar native type, so the caster rejects it with a
-     * Bad Request rather than leaving a raw value for the filter.
-     */
     #[DataProvider('emptyCasterProvider')]
-    public function testEmptyValueThrowsBadRequest(callable $caster): void
+    public function testEmptyValueIsReturnedUnchanged(callable $caster): void
     {
-        $this->expectException(BadRequestException::class);
-        $caster('');
+        $this->assertSame('', $caster(''));
     }
 
     public static function emptyCasterProvider(): \Generator

tests/Fixtures/TestBundle/ApiResource/ChoiceConstrainedScalarParameter/ChoiceConstrainedScalarParameter.php

@@ -0,0 +1,56 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Fixtures\TestBundle\ApiResource\ChoiceConstrainedScalarParameter;
+
+use ApiPlatform\Metadata\ApiResource;
+use ApiPlatform\Metadata\GetCollection;
+use ApiPlatform\Metadata\Operation;
+use ApiPlatform\Metadata\QueryParameter;
+use Symfony\Component\Validator\Constraints as Assert;
+
+#[ApiResource(
+    operations: [
+        new GetCollection(
+            uriTemplate: '/choice_constrained_scalar_parameters',
+            parameters: [
+                'days' => new QueryParameter(
+                    schema: ['type' => 'integer', 'enum' => self::DAYS],
+                    constraints: [new Assert\Choice(choices: self::DAYS)],
+                    castToNativeType: true,
+                ),
+                'ratio' => new QueryParameter(
+                    schema: ['type' => 'number', 'enum' => self::RATIOS],
+                    constraints: [new Assert\Choice(choices: self::RATIOS)],
+                    castToNativeType: true,
+                ),
+                'active' => new QueryParameter(
+                    schema: ['type' => 'boolean'],
+                    constraints: [new Assert\Choice(choices: [true, false])],
+                    castToNativeType: true,
+                ),
+            ],
+            provider: [self::class, 'provide'],
+        ),
+    ]
+)]
+class ChoiceConstrainedScalarParameter
+{
+    public const DAYS = [7, 30, 90];
+    public const RATIOS = [0.5, 1.5];
+
+    public static function provide(Operation $operation): array
+    {
+        return [];
+    }
+}

tests/Fixtures/TestBundle/Document/FilteredNumericParameter.php

@@ -19,6 +19,8 @@
 use ApiPlatform\Metadata\QueryParameter;
 use Doctrine\ODM\MongoDB\Mapping\Annotations as ODM;
 use Symfony\Component\TypeInfo\Type\BuiltinType;
+use Symfony\Component\TypeInfo\Type\CollectionType;
+use Symfony\Component\TypeInfo\Type\GenericType;
 use Symfony\Component\TypeInfo\TypeIdentifier;
 
 #[ApiResource]
@@ -36,6 +38,12 @@
             nativeType: new BuiltinType(TypeIdentifier::INT),
             castToNativeType: true,
         ),
+        'quantities' => new QueryParameter(
+            filter: new ExactFilter(),
+            property: 'quantity',
+            nativeType: new CollectionType(new GenericType(new BuiltinType(TypeIdentifier::ARRAY), new BuiltinType(TypeIdentifier::INT)), true),
+            castToNativeType: true,
+        ),
         'ratio' => new QueryParameter(
             filter: new ExactFilter(),
             nativeType: new BuiltinType(TypeIdentifier::FLOAT),

tests/Fixtures/TestBundle/Entity/FilteredNumericParameter.php

@@ -19,6 +19,8 @@
 use ApiPlatform\Metadata\QueryParameter;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Component\TypeInfo\Type\BuiltinType;
+use Symfony\Component\TypeInfo\Type\CollectionType;
+use Symfony\Component\TypeInfo\Type\GenericType;
 use Symfony\Component\TypeInfo\TypeIdentifier;
 
 #[ApiResource]
@@ -36,6 +38,12 @@
             nativeType: new BuiltinType(TypeIdentifier::INT),
             castToNativeType: true,
         ),
+        'quantities' => new QueryParameter(
+            filter: new ExactFilter(),
+            property: 'quantity',
+            nativeType: new CollectionType(new GenericType(new BuiltinType(TypeIdentifier::ARRAY), new BuiltinType(TypeIdentifier::INT)), true),
+            castToNativeType: true,
+        ),
         'ratio' => new QueryParameter(
             filter: new ExactFilter(),
             nativeType: new BuiltinType(TypeIdentifier::FLOAT),

tests/Functional/Parameters/BooleanFilterTest.php

@@ -76,16 +76,16 @@ public static function booleanFilterScenariosProvider(): \Generator
         yield 'enabled_alias_numeric_0' => ['/filtered_boolean_parameters?enabled=0', 1, false];
     }
 
-    /**
-     * An empty value cannot be cast to the boolean native type, so the caster rejects it with a
-     * Bad Request before the filter runs.
-     */
     #[DataProvider('booleanFilterEmptyScenariosProvider')]
     public function testBooleanFilterWithEmptyValues(string $url): void
     {
-        self::createClient()->request('GET', $url);
+        $response = self::createClient()->request('GET', $url);
+        $this->assertResponseIsSuccessful();
+
+        $filteredItems = $response->toArray()['hydra:member'];
 
-        $this->assertResponseStatusCodeSame(400);
+        $expectedItemCount = 3;
+        $this->assertCount($expectedItemCount, $filteredItems, \sprintf('Expected %d items for URL %s', $expectedItemCount, $url));
     }
 
     public static function booleanFilterEmptyScenariosProvider(): \Generator

tests/Functional/Parameters/EmptyScalarParameterTest.php

@@ -0,0 +1,61 @@
+<?php
+
+/*
+ * This file is part of the API Platform project.
+ *
+ * (c) Kévin Dunglas <dunglas@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace ApiPlatform\Tests\Functional\Parameters;
+
+use ApiPlatform\Symfony\Bundle\Test\ApiTestCase;
+use ApiPlatform\Tests\Fixtures\TestBundle\ApiResource\ChoiceConstrainedScalarParameter\ChoiceConstrainedScalarParameter;
+use ApiPlatform\Tests\SetupClassResourcesTrait;
+use PHPUnit\Framework\Attributes\DataProvider;
+
+final class EmptyScalarParameterTest extends ApiTestCase
+{
+    use SetupClassResourcesTrait;
+
+    protected static ?bool $alwaysBootKernel = false;
+
+    /**
+     * @return class-string[]
+     */
+    public static function getResources(): array
+    {
+        return [ChoiceConstrainedScalarParameter::class];
+    }
+
+    #[DataProvider('provideScalarParameters')]
+    public function testEmptyValueIsRejectedByConstraints(string $parameter): void
+    {
+        $response = self::createClient()->request('GET', '/choice_constrained_scalar_parameters?'.$parameter.'=');
+
+        $this->assertResponseStatusCodeSame(422);
+        $this->assertArraySubset([
+            'violations' => [
+                ['propertyPath' => $parameter, 'message' => 'The value you selected is not a valid choice.'],
+            ],
+        ], $response->toArray(false));
+    }
+
+    public static function provideScalarParameters(): \Generator
+    {
+        yield 'integer' => ['days'];
+        yield 'float' => ['ratio'];
+        yield 'boolean' => ['active'];
+    }
+
+    public function testUncastableValueIsRejectedByConstraints(): void
+    {
+        self::createClient()->request('GET', '/choice_constrained_scalar_parameters?days=foo');
+
+        $this->assertResponseStatusCodeSame(422);
+    }
+}

tests/Functional/Parameters/ExactFilterTest.php

@@ -87,6 +87,12 @@ public static function exactSearchFilterProvider(): \Generator
             0,
             [],
         ];
+
+        yield 'filter by an empty string-typed name still filters' => [
+            '/chickens?name=',
+            0,
+            [],
+        ];
     }
 
     public function testExactSearchFilterByCoopId(): void