Cakephp 3 - save data to belongstomany table - cakephp

Question

In Cakephp3, I have the following tables:
CREATE TABLE `users` (
`id` int(11) NOT NULL,
`name` varchar(45) DEFAULT NULL,
`created` datetime NOT NULL,
`modified` datetime DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `roles` (
`id` int(11) NOT NULL,
`title` varchar(45) DEFAULT NULL,
`created` datetime NOT NULL,
`modified` datetime DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
CREATE TABLE `roles_users` (
`id` int(11) NOT NULL,
`note` text,
`created` datetime DEFAULT NULL,
`modified` datetime DEFAULT NULL,
`role_id` int(11) NOT NULL,
`user_id` int(11) NOT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
My intention is, to edit the available fields in table 'roles_users' within the Users add & edit view (and the related controller actions). I considereded https://book.cakephp.org/3.0/en/views/helpers/form.html#associated-form-inputs, my user view (edit) look like:
<div class="users form large-9 medium-8 columns content">
<?= $this->Form->create($user) ?>
<fieldset>
<legend><?= __('Edit User') ?></legend>
<?php
echo $this->Form->control('name');
echo $this->Form->control('roles.0._joinData.role_id', ['type'=>'select', 'options' => $roles]);
echo $this->Form->control('roles.1._joinData.role_id', ['type'=>'select', 'options' => $roles]);
echo $this->Form->control('roles.2._joinData.role_id', ['type'=>'select', 'options' => $roles]);
?>
</fieldset>
<?= $this->Form->button(__('Submit')) ?>
<?= $this->Form->end() ?>
</div>
the underlying controller action is:
public function edit($id = null)
{
$user = $this->Users->get($id, [
'contain' => ['Roles']
]);
if ($this->request->is(['patch', 'post', 'put'])) {
$user = $this->Users->patchEntity($user,$this->request->getData());
pr($this->request->getData());
if ($this->Users->save($user)) {
$this->Flash->success(__('The user has been saved.'));
return $this->redirect(['action' => 'index']);
}
$this->Flash->error(__('The user could not be saved. Please, try again.'));
}
$roles = $this->Users->Roles->find('list', ['limit' => 200]);
$this->set(compact('user', 'roles'));
}
The correct data are displayed, while accessing the edit action. But when submitting the data (even unchanged) new records are saved to table 'roles'. How do I have to update the controller actions and the related views, to write data to the table 'roles_users'?

Answer 1

You need to add associated model in your patchEntity like below
$user = $this->Users->patchEntity($user,$this->request->getData(), [
'associated' => ['RolesUsers']
]);
https://book.cakephp.org/3.0/en/orm/saving-data.html#

Answer 2

echo $this->Form->control('roles.0._joinData.role_id', ['type'=>'select', 'options' => $roles])
to:
echo $this->Form->control('roles.0.id', ['type'=>'select', 'options' => $roles])
echo $this->Form->control('roles.1.id', ['type'=>'select', 'options' => $roles])