Laravel 6 with function not showing related data - php

Question

I've made a really simple function in Laravel 6 that uses with():
$forms = Form::with('itemsForms')->get();
return response()->json([
'code' => 200,
'data' => $forms
]);
The following are the relationships between Form and ItemsForm:
//Form
protected $fillable = [
'title',
'subtitle',
'text',
'name',
'email',
'phone_number',
'address',
'board',
'date',
'file',
'purchasable',
'payment_for',
'invoice_amount',
];
protected $visible = [
'title',
'subtitle',
'text',
'name',
'email',
'phone_number',
'address',
'board',
'date',
'file',
'purchasable',
'payment_for',
'invoice_amount',
];
public function itemsForms()
{
return $this->hasMany('App\ItemsForm');
}
//ItemsForm
protected $fillable = [
'item_id', 'form_id'
];
public function form()
{
return $this->belongsTo('App\Form', 'form_id');
}
The thing is it doesn't retrieve any data from ItemsForm.
Here's some of what I've tried:
I tried changing parameter in with to other similar names but in each case I got an error of "relationship not found" or something like that. When I use itemsForms I get no error.
I tried debugging it enabling the query log. Here's what I got:
array:2 [
0 => array:3 [
"query" => "select * from `forms`"
"bindings" => []
"time" => 5.77
]
1 => array:3 [
"query" => "select * from `items_forms` where `items_forms`.`form_id` in (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)"
"bindings" => []
"time" => 1.03
]
]
I tried getting the ItemsForm data and it retrieves it with no issue (ItemsForm::all()).
Any idea of what could be causing this?
Edit: the schema for ItemsForm is the following:
Schema::create('items_forms', function (Blueprint $table) {
$table->bigIncrements('id');
$table->unsignedBigInteger('item_id');
$table->unsignedBigInteger('form_id');
$table->foreign('item_id')
->references('id')->on('items')
->onDelete('no action')
->onUpdate('no action');
$table->foreign('form_id')
->references('id')->on('forms')
->onDelete('no action')
->onUpdate('no action');
});

Answer 1

Change the relationship as follows..
In Form class
public function itemsForms()
{
return $this->hasMany('App\ItemsForm','form_id','id');
}
In ItemsForm
public function form()
{
return $this->belongsTo('App\Form', 'id','form_id');
}
You can use the relationship as
$res = Form::find($id);
foreach($res->itemsForms as $item)
{
echo $item->item_id;
}

Answer 2

I finally found out what the issue was.
The issue was I didn't include itemsForms in the visible array (even though it is not part of the database fields).
There was no particular reason to include the visible array in my case so I deleted it but if I had wanted to keep it I should have included itemsForms as an element of the array.