Action / GET with limited properties - api-platform.com

Question

Certainly already asked but...
Having this entity
/**
* A form
*
* #ORM\Entity(repositoryClass=FormRepository::class)
*
* #ORM\Table(
* name="forms",
* options={"comment":"Table of the forms"},
* indexes={
* #ORM\Index(name="forms_idx_dofc", columns={"dateofcreation"}),
* #ORM\Index(name="forms_idx_dofu", columns={"dateofupdate"}),
* #ORM\Index(name="forms_idx_dofs", columns={"dateofsubmission"})
* }
* )
*
* #ApiResource(
* routePrefix="/",
* shortName="Forms",
* description="API Access : form Entity",
* collectionOperations={"GET"},
* itemOperations={"GET"},
* attributes={
* "normalization_context"={
* "groups"={
* "GET:FORM"
* }
* },
* "order"={
* "dateofsubmission",
* "dateofupdate",
* "dateofcreation"
* }
* }
* )
*
*/
class Form
{
/**
* #ORM\Id
* #ORM\GeneratedValue
* #ORM\Column(type="integer", options={"comment":"Primary Key, Auto generated"})
*/
private $id;
/**
* #var datetime Date of creation of the form.
*
* #ORM\Column(type="datetime", options={"comment":"date of creation of the form"})
*
* #Assert\NotBlank(message="The date time when was created the form should not be blank")
* #Assert\DateTime(message="The data time when was created the form should be the type DateTime")
*
* #Groups({"GET:FORM"})
*
* #ApiFilter(OrderFilter::class, strategy="ASC")
*/
private $dateofcreation;
/**
* #var datetime Date of update of the form.
*
* #ORM\Column(type="datetime", options={"comment":"date of update of the form"})
*
* #Assert\NotBlank(message="The date time when was updated the form should not be blank")
* #Assert\DateTime(message="The data time when was updated the form should be the type DateTime")
*
* #Groups({"GET:FORM"})
*
* #ApiFilter(OrderFilter::class, strategy="ASC")
*/
private $dateofupdate;
/**
* #var person Person that has created the form.
*
* #ORM\ManyToOne(targetEntity=Person::class, inversedBy="forms")
* #ORM\JoinColumn(nullable=false)
*
* #Groups({"GET:FORM"})
*
* #ApiFilter(SearchFilter::class, properties={"createdBy.id":"exact","createdBy.givenname":"ipartial", "createdBy.familyname":"ipartial"})
* #ApiFilter(OrderFilter::class, strategy="ASC")
*/
private $createdBy;
...
I would like to have the possibility of having :
A base collectionOperations "GET" would return all the properties that have the #GROUP=GET:FORM
A alternate collectionOperations "GETDATES" would return all properties that have a #GROUP=GET:DATES
The operations being accessible (ideally) with different routes.
GET => # http://api/forms?createdBy.id=25 => All properties
GETDATES => http://api/formsLimited?createdBy.id=25 => only the dates
ps: I hope this is better for the readability.

Answer 1

Thanks to Grégoire Hébert(https://stackoverflow.com/users/4887997/gr%C3%A9goire-hebert) for the support (on Slack).
The solution is quite simple.
Create in the ApiResource() a collection operation with:
Method = GET
path (that will become a route)
the normalization context for the group to be applied to the wanted properties
It gives:
collectionOperations={"GET","GETLIMITED"={"method"="GET","path"="formslist","normalization_context"={"groups"="GET:LIMITED"}}},