Webapi: nullable nested objects does not support null

[stollr]

Preconditions and environment

• Magento version 2.4.6-p12

Steps to reproduce

I have a webapi service that handles an object as input, which has a nullable property which is another object. When null is provided as value for the nested object, I get an error.

Here are the files needed to reproduce the issue:

namespace Stollr\CrmApi\Api\Data;

interface TestTypeInterface
{
    /**
     * @return string
     */
    public function getName(): string;

    /**
     * @param string $name
     * @return void
     */
    public function setName(string $name): void;

    /**
     * @return \Stollr\CrmApi\Api\Data\TestTypeNestedInterface|null
     */
    public function getNestedType(): ?TestTypeNestedInterface;

    /**
     * @param \Stollr\CrmApi\Api\Data\TestTypeNestedInterface|null $nestedType
     * @return void
     */
    public function setNestedType(?TestTypeNestedInterface $nestedType): void;
}

namespace Stollr\CrmApi\Api\Data;

interface TestTypeNestedInterface
{
    /**
     * @return string
     */
    public function getName(): string;

    /**
     * @param string $name
     * @return void
     */
    public function setName(string $name): void;
}

namespace Stollr\CrmApi\Api\Webapi;

use Stollr\CrmApi\Api\Data\TestTypeInterface;

interface TestNestedNullableWebapiInterface
{
    /**
     * @param \Stollr\CrmApi\Api\Data\TestTypeInterface $type
     * @return \Stollr\CrmApi\Api\Data\TestTypeInterface
     */
    public function save(TestTypeInterface $type): TestTypeInterface;
}

namespace Stollr\CrmApi\Model\Data;

use Stollr\CrmApi\Api\Data\TestTypeInterface;
use Stollr\CrmApi\Api\Data\TestTypeNestedInterface;

class TestType implements TestTypeInterface
{
    /**
     * @param string $name
     * @param \Stollr\CrmApi\Api\Data\TestTypeNestedInterface|null $nestedType
     */
    public function __construct(
        private string $name,
        private ?TestTypeNestedInterface $nestedType = null,
    ) {
    }

    public function getName(): string
    {
        return $this->name;
    }

    public function setName(string $name): void
    {
        $this->name = $name;
    }

    public function getNestedType(): ?TestTypeNestedInterface
    {
        return $this->nestedType;
    }

    public function setNestedType(?TestTypeNestedInterface $nestedType): void
    {
        $this->nestedType = $nestedType;
    }
}

namespace Stollr\CrmApi\Model\Data;

use Stollr\CrmApi\Api\Data\TestTypeNestedInterface;

class TestTypeNested implements TestTypeNestedInterface
{
    /**
     * @param string $name
     */
    public function __construct(private string $name) {}

    public function getName(): string
    {
        return $this->name;
    }

    public function setName(string $name): void
    {
        $this->name = $name;
    }
}

namespace Stollr\CrmApi\Webapi;

use Stollr\CrmApi\Api\Data\TestTypeInterface;
use Stollr\CrmApi\Api\Webapi\TestNestedNullableWebapiInterface;

class TestNestedNullableWebapi implements TestNestedNullableWebapiInterface
{
    public function save(TestTypeInterface $type): TestTypeInterface
    {
        return $type;
    }
}

<!-- etc/di.xml -->
<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Stollr\CrmApi\Api\Data\TestTypeInterface" type="Stollr\CrmApi\Model\Data\TestType"/>
    <preference for="Stollr\CrmApi\Api\Data\TestTypeNestedInterface" type="Stollr\CrmApi\Model\Data\TestTypeNested"/>
    <preference for="Stollr\CrmApi\Api\Webapi\TestNestedNullableWebapiInterface" type="Stollr\CrmApi\Webapi\TestNestedNullableWebapi"/>
</config>

<!-- etc/webapi.xml -->
<?xml version="1.0"?>
<routes xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Webapi:etc/webapi.xsd">
    <route url="/V1/test-nested-nullable" method="POST">
        <service class="Stollr\CrmApi\Api\Webapi\TestNestedNullableWebapiInterface" method="save"/>
        <resources>
            <resource ref="anonymous"/>
        </resources>
    </route>
</routes>

The important thing is that in TestType the nestedType property is nullable.

Now, I call the API service with POST https://localhost/rest/V1/test-nested-nullable and the following request body:

{
  "type": {
    "name": "test",
    "nested_type": null
  }
}

Expected result

I get a response with the status code 200 and the json object.

Actual result

In fact I get a 400 error with the following content:

{
"message": "Type Error occurred when creating object: %type, %msg",
"parameters": {
"type": "Stollr\CrmApi\Model\Data\TestTypeNested",
"msg": "Stollr\CrmApi\Model\Data\TestTypeNested::__construct(): Argument #1 ($name) must be of type string, null given, called in /var/www/html/magento/vendor/magento/framework/ObjectManager/Factory/AbstractFactory.php on line 121"
},
"trace": "#0 /var/www/html/magento/vendor/magento/framework/ObjectManager/Factory/Compiled.php(108): Magento\Framework\ObjectManager\Factory\AbstractFactory->createObject('Stollr\\CrmApi\\...', Array)\n#1 /var/www/html/magento/vendor/magento/framework/ObjectManager/ObjectManager.php(56): Magento\Framework\ObjectManager\Factory\Compiled->create('Stollr\\CrmApi\\...', Array)\n#2 /var/www/html/magento/vendor/magento/framework/Webapi/ServiceInputProcessor.php(298): Magento\Framework\ObjectManager\ObjectManager->create('\\Stollr\\CrmApi...', Array)\n#3 /var/www/html/magento/vendor/magento/framework/Webapi/ServiceInputProcessor.php(537): Magento\Framework\Webapi\ServiceInputProcessor->_createFromArray('\\Stollr\\CrmApi...', Array)\n#4 /var/www/html/magento/vendor/magento/framework/Webapi/ServiceInputProcessor.php(329): Magento\Framework\Webapi\ServiceInputProcessor->convertValue(NULL, '\\Stollr\\CrmApi...')\n#5 /var/www/html/magento/vendor/magento/framework/Webapi/ServiceInputProcessor.php(537): Magento\Framework\Webapi\ServiceInputProcessor->_createFromArray('Stollr\\CrmApi\\...', Array)\n#6 /var/www/html/magento/vendor/magento/framework/Webapi/ServiceInputProcessor.php(200): Magento\Framework\Webapi\ServiceInputProcessor->convertValue(Array, 'Stollr\\CrmApi\\...')
[...]
}

Additional information

I think the relevant code for this issue is in Magento\Framework\Webapi\ServiceInputProcessor.
In this line a check could be added, and if $value === null then $setterValue should be set to null.

Trying to convert null to anything else does not make sense.

I hope this helps.

Release note

No response

Triage and priority

• Severity: S0 - Affects critical data or functionality and leaves users without workaround.
• Severity: S1 - Affects critical data or functionality and forces users to employ a workaround.
• Severity: S2 - Affects non-critical data or functionality and forces users to employ a workaround.
• Severity: S3 - Affects non-critical data or functionality and does not force users to employ a workaround.
• Severity: S4 - Affects aesthetics, professional look and feel, “quality” or “usability”.

[m2-assistant]

Hi @stollr. Thank you for your report.
To speed up processing of this issue, make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce.

• For more details, review the Magento Contributor Assistant documentation.
• Add a comment to assign the issue: @magento I am working on this
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