Circular reference detected when using fos:elastica:populate

Question

I was until now using the Groups annotation to serialize and populate my Elastic search index, and it was working fine as it was only using the fields in the group "elastica", and only for the Entities listed in my fos_elastica.yml. So I could control easily which field was sent in my index and avoid circular references.

The issue now is that I need to set some relationships as "nested" in my index, and couldn't find how to do this with the Groups annotations, so I decided to configure my types in my fos_elastica.yml...

But now the Serializer wants to serialize fields I don't ask him to (or at least I don't think I am...)

fos_elastica:
serializer: ~
clients:
     default:
         url: '%elasticsearch.url%'
         logger: true
indexes:
    alternance:
        finder: ~
        use_alias: true
        index_name: '%elastic_index_name%'
        types:
            offer:
                mappings:
                    id: { type: integer }
                    name: ~
                    slug: ~
                    metaTitle: ~
                    metaDescription: ~
                    metaKeywords: ~
                    content: ~
                    duration: ~
                    startat: ~
                    keywords: ~
                    email: ~
                    wage: ~
                    profile: ~
                    premiumFlag: ~
                    idValid: { type: integer }
                    updated: ~
                    created: ~
                    levels:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                    diplomas:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                    company:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                    domains:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                    contract:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                    city:
                        type: nested
                        properties:
                            id: { type: integer }
                            name: ~
                            slug: ~
                            metaTitle: ~
                            metaDescription: ~
                            metaKeywords: ~
                            content: ~
                            county:
                                type: nested
                                properties:
                                    id: { type: integer }
                                    name: ~
                                    slug: ~
                                    metaTitle: ~
                                    metaDescription: ~
                                    metaKeywords: ~
                                    content: ~
                                    region:
                                        type: nested
                                        properties:
                                            id: { type: integer }
                                            name: ~
                                            slug: ~
                                            metaTitle: ~
                                            metaDescription: ~
                                            metaKeywords: ~
                                            content: ~
                persistence:
                    driver: orm
                    model: ModelBundle\Entity\Offer
                    provider: ~

When I run bin\console fos:elastica:populate, I get this error : A circular reference has been detected when serializing the object of class "Proxies__CG__\ModelBundle\Entity\County"

So I'm assuming it's trying to serialize County, and finds out that there is a OneToMany relationship "Cities", but in my configuration file I'm not asking him to serialize the "Cities" field ??

Can I force the serializer to ignore/not serialize the circular references ? All I can find regarding circular references handling is not in the entities classes/yml configuration :(

Here is the entities configuration :

//OFFER

/**
     * @ORM\ManyToOne(targetEntity="City", inversedBy="offers")
     * @ORM\JoinColumn(name="city_id", referencedColumnName="id", nullable=false)
     */
    private $city;

// CITY

/**
 * @ORM\ManyToOne(targetEntity="ModelBundle\Entity\County", inversedBy="cities")
 * @ORM\JoinColumn(name="county_id", referencedColumnName="id", nullable=false)
 */
private $county;

/**
 * @ORM\OneToMany(targetEntity="ModelBundle\Entity\Offer", cascade={"remove"}, mappedBy="city", fetch="EAGER")
 * @ORM\JoinColumn(onDelete="CASCADE", nullable=true)
 */
private $offers;

// COUNTY

/**
 * @ORM\OneToMany(targetEntity="ModelBundle\Entity\City", cascade={"remove"}, mappedBy="county", fetch="EAGER")
 * @ORM\JoinColumn(onDelete="CASCADE", nullable=true)
 */
private $cities;

Answer 1

Apparently just removing the

serializer: ~

l.2 fixed the issue :D