Association finding wrong table - cakephp

Question

I am trying to get contain the Children of my DomainTypes table for my DomainTypes view() function but it is complaining with "Error: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'Children.domain_type_id' in 'where clause'" The problem is that my DomainTypes table doesn't have a domain_type_id column. The Domain table does. Here is the code for my DomainTypes view():
public function view($id) {
if (!$id) {
throw new NotFoundException(__('Invalid DomainType'));
}
$domainType = $this->DomainTypes
->find()
->where(['DomainTypes.id' => $id])
->contain(['Parent', 'Children', 'Affiliates'])
->first();
$this->set(compact('domainType'));
}
So a little about my setup. I have 2 tables, Domains and DomainTypes. Both use the Tree behavior.
Here is the initialize code for the Domain Table:
public function initialize(array $config){
parent::initialize($config);
$this->displayField('name');
$this->addBehavior('Tree');
//Associations
$this->hasMany('Children', [
'className' => 'Domains',
]);
$this->belongsTo('Parent', [
'className' => 'Domains',
]);
$this->belongsTo('Affiliates');
$this->belongsTo('DomainTypes');
}
And here is the initialize code for the DomainTypes Table:
public function initialize(array $config){
parent::initialize($config);
$this->displayField('name');
$this->addBehavior('Tree');
//Associations
$this->hasMany('Children', [
'className' => 'DomainTypes',
]);
$this->belongsTo('Parent', [
'className' => 'DomainTypes',
]);
$this->belongsTo('Affiliates');
$this->hasMany('Domains');
}
Both very similar but also clearly defining which className to use. Why is Cakephp 3 assuming there is a domain_type_id column on my DomainTypes table? Thanks in advance!

Answer 1

We were both close, but not quite right. ndm, your answer was helpful though as it did point to another mistake I was making. The final association code should look like this:
$this->hasMany('Children', [
'className' => 'DomainTypes',
'foreignKey' => 'parent_id',
]);
$this->belongsTo('Parent', [
'className' => 'DomainTypes',
]);
When I was trying to enter the foreign key, Instead of "foreignKey", I was using "foreign_key" which was pretty much useless. Thanks for the help ndm.

Answer 2

Update I wasn't paying attention properly, and CakePHP seems to be actually correct when it auto-generates a foreign key named domain_type_id, it's a hasMany association and so the FK should be based on the source table.
The solution is still the same, the FK needs to be set explictly, and as already figured by #MjGaiser the parent_id for the belongsTo association isn't necessary, and instead the FK for the hasMany association should use parent_id instead of child_id:
$this->hasMany('Children', [
'className' => 'DomainTypes',
'foreignKey' => 'parent_id'
]);
$this->belongsTo('Parent', [
'className' => 'DomainTypes'
]);