Add refrences to MongoDB schema within Symfony project - mongodb

Question

I'm trying to create MongoDB database with some references within Symfony.
In my context I have 2 documents Customer and Meeting, One Customer can have Many Meeting so that what I did :
Meeting.php
<?php
namespace FrontOfficeBundle\Document;
use Doctrine\ODM\MongoDB\Mapping\Annotations as MongoDB;
/**
* #MongoDB\Document
*/
class Meeting
{
/**
* #MongoDB\Id
* #MongoDB\ReferenceOne(targetDocument="Customer")
*/
protected $id;
/**
* #MongoDB\Field(type="timestamp")
*/
protected $creationDate;
...
Customer.php
<?php
namespace FrontOfficeBundle\Document;
use Doctrine\ODM\MongoDB\Mapping\Annotations as MongoDB;
/**
* #MongoDB\Document
*/
class Customer
{
/**
* #MongoDB\Id()
* #MongoDB\ReferenceMany(targetDocument="Meeting")
*/
protected $id;
/**
* #MongoDB\Field(type="string")
*/
protected $username;
...
and then when I run the command line:
php bin/console doctrine:mongodb:schema:update
I got :
No identifier/primary key specified for Document 'FrontOfficeBundle\Document\Meeting'. Every Document must have an identifier/primary key.
I tried by using #MongoDB\UniqueIndex() but no way.
I think that #MongoDB\Id is supposed as an identifier !!!
Versions
Symfony 3.2
MongoDB 3.4.4
Any ideas ?
Thanks you.

Answer 1

Finally I found a solution, first I added a field called $meetings in the document Customer and an other $customer in the document meeting like this :
Customer.php
/**
* #MongoDB\ReferenceMany(targetDocument="meeting", mappedBy="customer")
*/
protected $meetings;
Meeting.php
/**
* #MongoDB\ReferenceOne(targetDocument="customer", inversedBy="meetings")
*/
protected $customer;
Then run the command line to generate setters and getters:
php bin/console doctrine:mongodb:generate:documents mybundleBundle
And when I run a fixtures (Creating one customer then its meeting), everything work fine, you'll notice that the relationship 1 to many has been defined in your document (I'm using compass to display mongoDB) as a One-to-Squillions model (for more details about 1-to-N relationship : (https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-1) that's mean the son document (meeting) contains the reference of the parent as shown below :
Customer
Meeting
In MongoDB the #MongDB/Id is a primary key and the foreign key and never try to define references to this unique field.
Thanks for your attention.