How to use the user ID as a foreign key? - php

Question

I have two tables, 'users' and 'posts', looking like this:
users:
- id
- username
- password
...
posts:
- id
- user_id (foreign key referencing users.id)
- text
Basically, a user has multiple posts (blog-type posts). Now, I'm trying to create a new post as a logged in user, but I can't get it to work. Here's what I've done:
// 'User' model
class User extends AppModel
{
public $name = 'User';
public $hasMany = array('Post');
...
// 'Post' model
class Post extends AppModel
{
public $name = 'Post';
public $belongsTo = array(
'User' => array(
'className' => 'User',
'foreignKey' => 'user_id'
)
);
// In PostsController
public function create()
{
if($this->request->is('post'))
{
$this->Post->create();
if($this->Post->save($this->request->data)
{
// Success
}
}
}
// In the post view
<?php echo $this->Session->flash('auth'); ?>
<?php echo $this->Form->create('Post', array('action' => 'create')); ?>
<fieldset>
<legend>
<?php echo __("Write a post"); ?>
</legend>
</fieldset>
<?php echo $this->Form->end(__('Post')); ?>
If I write a post and click 'Post', I get an integrity constraint violation:
Error: SQLSTATE[23000]: Integrity constraint violation:
1452 Cannot add or update a child row: a foreign key
constraint fails (`yams`.`posts`, CONSTRAINT `user_id`
FOREIGN KEY (`user_id`) REFERENCES `users` (`id`)
ON DELETE NO ACTION ON UPDATE NO ACTION)
Am I missing something here? It looks like the user id is not saved to the model.
EDIT:
I forgot to mention, the database error also prints out the SQL query which is clearly wrong:
INSERT INTO `yams`.`posts` (`text`) VALUES ('this is a test post.')
There's no ID whatsoever...

Answer 1

You need to do this:
// In PostsController
public function create()
{
if($this->request->is('post'))
{
$this->request->data['Post']['user_id'] = $this->Auth->user('id');
$this->Post->create();
if($this->Post->save($this->request->data)
{
// Success
}
}
}

Answer 2

I am just copying the book here, i have not used cakePHP at all!
According to the book: http://book.cakephp.org/2.0/en/models/associations-linking-models-together.html then a 'hasMany' relationship should look similar to:
class User extends AppModel {
public $hasMany = array(
'Recipe' => array(
'className' => 'Recipe',
'conditions' => array('Recipe.approved' => '1'),
'order' => 'Recipe.created DESC'
)
);
}
You have:
public $hasMany = array('Post');
Should there be mention of a classname in yours?
i.e.
public $hasMany = array(
'Post' => array(
'className' => 'Post'
)
);
With this then the ORM can work out how the classes relate and what to fill in at run time.