Cannot save associated data with hasMany through (Join Model) - php

Question

Hi, I am new to cakephp and doing a project on cakephp 2.3.4.
I have to associate product metal class through has many through association . But it doesn't seem to be working.
Model code
class Metal extends AppModel {
public $hasMany = array(
'MetalProduct'
);
}
class Product extends AppModel {
public $hasMany = array(
'MetalProduct'
);
}
App::uses('AppModel', 'Model');
class MetalProduct extends AppModel {
public $belongsTo = array(
'Metal' => array(
'className' => 'Metal',
'foreignKey' => 'metal_id'
),
'Product' => array(
'className' => 'Product',
'foreignKey' => 'product_id'
)
);}
My database table names are metal, products and metal_products
I have multiple select option for selecting more than one metal type.
This is how I get the the list of metals
$metals=$this->Metal->find('list');
$this->set(compact('metals'));
FormHelper code for listbox is
<?php echo $this->Form->input('Metal',array('type' => 'select',
'multiple' => true)); ?>
The product is getting saved successfully but the associations are not.
The debug array give me this
$message = array(
'Product' => array(
'category_id' => '517a514b-0eb0-4ec9-b018-0b948620d4f0',
'name' => 'mangalsutra Diamond',
'slug' => 'mangalsutra_diamond',
'description' => '1212',
'Metal' => array(
(int) 0 => '5183cb65-bf90-459c-b22e-0b748620d4f0',
(int) 1 => '5183ce25-c744-433e-b035-0b748620d4f0'
),
'image' => '121212',
'price' => '12121',
'weight' => '12',
'active' => '1',
'category' => 'Mangalsutra'
)
)
I had put my head through walls but no clue why the associations are not getting saved.
The way they say in tutorials it seems easy, but why its not working?
I have doubts that its not saving because the metal array is passed like this
'Metal' => array(
(int) 0 => '5183cb65-bf90-459c-b22e-0b748620d4f0',
(int) 1 => '5183ce25-c744-433e-b035-0b748620d4f0'
),
It should mention 'id''rather than (int) 0 or something.
Also, my database table for metal_products which I have created manually has
id(primary key)
metal_id(foreign key to Metal.id)
product_id(foreign key to Product.id)
Am I doing something wrong with naming conventions or the way database is created?
Please give me correct ans cause anything I tried from others answer is not working
I am saving it via
$this->Product->saveAll($this->request->data, array('deep' => true))

Answer 1

In your model, is all of that in your MetalProduct Model? If so you need to move
class Metal extends AppModel {
public $hasMany = array(
'MetalProduct'
);
}
to the Metal model and
class Product extends AppModel {
public $hasMany = array(
'MetalProduct'
);
}
to the Product Model
Also add your belongsTo to each Model
I see you have a join table. Join tables are usually for HABTM associations. This is a HasMany. You need to use the other options available to define the foreign key relationships in each model as outlined above.
Please see the examples on the Cake Documentation.
http://book.cakephp.org/2.0/en/models/associations-linking-models-together.html
Also, if you are unsure of how to set up the models correctly, you can always use the Bake feature of Cakephp to generate the models and code for you in that regard.
book.cakephp.org/2.0/en/console-and-shells/code-generation-with-bake.html
If you are more of a visual learner this video tut should help you through the basics
http://www.youtube.com/watch?v=kJAMifqF5s8

Answer 2

The Relation i generated using Bake looks something like this
class Product extends AppModel {
/**
* hasAndBelongsToMany associations
*/
public $hasAndBelongsToMany = array(
'Metal' => array(
'className' => 'Metal',
'joinTable' => 'metals_products',
'foreignKey' => 'product_id',
'associationForeignKey' => 'metal_id',
'unique' => 'keepExisting',
'conditions' => '',
'fields' => '',
'order' => '',
'limit' => '',
'offset' => '',
'finderQuery' => '',
'deleteQuery' => '',
'insertQuery' => ''
));
}
class Metal extends AppModel {
/** hasAndBelongsToMany associations */
public $hasAndBelongsToMany = array(
'Product' => array(
'className' => 'Product',
'joinTable' => 'metals_products',
'foreignKey' => 'metal_id',
'associationForeignKey' => 'product_id',
'unique' => 'keepExisting',
'conditions' => '',
'fields' => '',
'order' => '',
'limit' => '',
'offset' => '',
'finderQuery' => '',
'deleteQuery' => '',
'insertQuery' => ''
));
}
/**
* MetalsProduct Model
* #property Product $Product
* #property Metal $Metal
*/
class MetalsProduct extends AppModel {
/* belongsTo associations */
public $belongsTo = array(
'Product' => array(
'className' => 'Product',
'foreignKey' => 'product_id',
'conditions' => '',
'fields' => '',
'order' => ''
),
'Metal' => array(
'className' => 'Metal',
'foreignKey' => 'metal_id',
'conditions' => '',
'fields' => '',
'order' => ''
));
}
This worked for me flawlessly.
Hope it works for all.