Using JMSSerializer (or its bundle) serialized field are renamed by default to the underscore-separated words naming convention. If like me you prefer camel-case naming and you want fields serialized as it, there's two solutions.
1. Set serialize name for each fields
2. Change the whole naming strategy
If like me you don't want to set the serialized name for each field, you can change the naming strategy by your custom one or the simple
IdenticalPropertyNamingStrategy that don't rename fields.
The first solution is to set the naming strategy while creating your serializer using the
return SerializerBuilder::create() ->setPropertyNamingStrategy(new SerializedNameAnnotationStrategy(new PassThroughNamingStrategy())) ->build();
The second solution if you use the bundle is to override the
jms_serializer.camel_case_naming_strategy.class parameter in your
parameters: jms_serializer.camel_case_naming_strategy.class: JMS\Serializer\Naming\IdenticalPropertyNamingStrategy