CakePhp 3 Save data in belongsTo - cakephp

Question

So, i have problem with saving data to DB
Model Table is
...
$this->belongsTo('Users', [
'foreignKey' => 'user_id',
'joinType' => 'INNER'
]);
...
I want to store new Address in row and data structure is
object(App\Model\Entity\Address) {
'type' => (int) 1,
'Users' => [
'user_id' => '9'
],
'short_name' => 'Test',
'long_name' => 'test',
'additional_name' => 'test',
I have tried in controller
if ($this->request->is('post')) {
$address = $this->Addresses->patchEntity($address, $this->request->data, ['associated' => ['Users.user_id']]);
if ($this->Addresses->save($address)) {
$this->Flash->success(__('The address has been saved.'));
return $this->redirect(['action' => 'index']);
} else {
$this->Flash->error(__('The address could not be saved. Please, try again.'));
}
And in my template view this is input field
echo $this->Form->input('Users.user_id', ['type' => 'select', 'options' => $groups, 'class' => 'form-control']);
echo $this->Form->input('short_name', ['class' => 'form-control']);
echo $this->Form->input('long_name', ['class' => 'form-control']);
So, what can I do? How to reorganize data stucture?
Thank you!

Answer 1

You are using the CakePHP <= 2.x styled naming conventions for your inputs, that's not how it works with CakePHP 3.x anymore.
Please refer to the docs on how to create inputs for associated data:
Cookbook > Views > Helpers > Form > Creating Inputs for Associated Data
You have to use the appropriate property name of the association, just as it appears in the entity when reading data. For belongsTo associations, this is by default the singular, underscored variant of the association alias, so in your case user, ie
echo $this->Form->input('user.user_id', [
'type' => 'select',
'options' => $groups,
'class' => 'form-control'
]);
See also
Cookbook > Database Access & ORM > Associations > BelongsTo Associations
Cookbook > Database Access & ORM > Saving Data > Saving BelongsTo Associations
Cookbook > Views > Helpers > Form > Field Naming Conventions