[Serializer] Add context for CamelCaseToSnakeCaseNameConverter

[AurelienPillevesse]

Q	A
Branch?	7.1
Bug fix?	no
New feature?	yes
Deprecations?	no
Issues
License	MIT

Currently, when we use a Symfony 7.0 project (or 6.4 for example) with the symfony/serializer component installed.

With the #[MapRequestPayload] feature and this configuration :

framework:
    serializer:
        name_converter: 'serializer.name_converter.camel_case_to_snake_case'

This configuration forces Symfony to return to the snake case format.
But when sending these two POST requests :

{
    "lastName": "MyLastName"
}

{
    "last_name": "MyLastName"
}

They will be handled exactly the same.

The idea is to add a context CamelCaseToSnakeCaseNameConverter::REQUIRE_SNAKE_CASE_PROPERTIES which can be used in #[MapRequestPayload] attribute to only accept the POST request with last_name attribute body.

Example :

class MyRouteInput
{
    public string $lastName;
}

#[MapRequestPayload(serializationContext: [CamelCaseToSnakeCaseNameConverter::REQUIRE_SNAKE_CASE_PROPERTIES => true])]
MyRouteInput $input

[Note]
This is a first draft to expose my idea. The exception thrown and where the new condition is added can probably be improved.
A possible improvement can be to use the existing logic with PartialDenormalizationException.
If for you it can added in 6.4 and 7.0 instead of 7.1, i'm OK.

[OskarStark]

Please add a test case to avoid further regression, thanks

[fabpot]

Thank you @AurelienPillevesse.

[soyuka]

Isn't this is a bc-break as both interfaces (AdvancedNameConverterInterface and the NameConverterInterface) are not compatible and this class is not internal. One could extend the current CamelCaseToSnakeCaseNameConverter.

[nicolas-grekas]

Yes it is. @AurelienPillevesse can you please have a look?

[AurelienPillevesse]

@nicolas-grekas How can we implement this feature without changing the interface ?

[xabbuh]

I suggest that we add the arguments to the NameConverterInterface (in 8.0) instead: #54531