Eloquent relationship in custom pivot table - laravel

Question

I might be overcomplicating things, but here's relationship I'm trying to write in Eloquent (Laravel 5):
I have a list of products and price lists. Each product can have many price lists. This is easy to do, but here's another thing - for every product <> price list assignment I can have many prices based on quantity, so it's like:
productID: 1010
priceListId: 1
min quantity: 1 -> price 10.00
min quantity: 5 -> price 9.50
min quantity: 10 -> price 9.00
productID: 1010
priceListId: 2
min quantity: 1 -> price 15.00
min quantity: 40 -> price 14.00
min quantity: 90 -> price 12.00
I think I know how to create custom pivot table although I don't know how to use it. I followed this link now I'm not sure if my code is correct and how to use it.
At the moment I have:
Product model:
class Product extends Model {
public function pricelists()
{
return $this->belongsToMany('PriceList');
}
public function newPivot(Model $parent, array $attributes, $table, $exists)
{
if ($parent instanceof PriceList)
{
return new ProductPricePivot($parent, $attributes, $table, $exists);
}
return parent::newPivot($parent, $attributes, $table, $exists);
}
}
PriceList model:
class PriceList extends Model {
public function products()
{
return $this->belongsToMany('Product');
}
public function newPivot(Model $parent, array $attributes, $table, $exists)
{
if ($parent instanceof Product)
{
return new ProductPricePivot($parent, $attributes, $table, $exists);
}
return parent::newPivot($parent, $attributes, $table, $exists);
}
}
Pivot:
class ProductPricePivot extends Pivot {
public function product()
{
return $this->belongsTo('Product');
}
public function pricelist()
{
return $this->belongsTo('PriceList');
}
public function prices()
{
return $this->hasMany('ProductPrice');
}
}
Now ProductPrice extends Model again and is just a standard model without any additional methods.
Is this correct? If so, then following example from above, how can I add new quantity/price level to price list 1 on product 1010?
At the moment, when creating relationships, I'm doing:
$productID = 1010;
$priceListID = 1;
$priceList = PriceList::find($priceListID);
$priceList->products()->attach($productID);
$productToPriceList = $priceList->products()->find($productID);
And I'm lost here... I find this relationship, but how can I now attach next quantity <> price level to it?
Can someone please give an example of how to use such relationship or links to pages where I can find something more about it? And yes, I check Laravel documentation, and yes, I googled it as well.
Thank you!

Answer 1

As you described the case, I see here two types of relationships:
Many-to-Many relationship between Product & PriceList
Many-to-One relationship between PriceList & ProductPrice (which holds the "min-quantity" and "price") values.
I'm assuming that you don't need the same price condition for many "price-list"s. Every list will have it's price conditions.
Many-to-one relationship doesn't require pivot table.
Follow this link, you'll find that laravel Eloquent system helps you much.
You need 4 tables: products, price_lists, product_prices, products_to_pricelists (the pivot)
the products_to_pricelists table look like that:
*====*============*===============*
| id | product_id | price_list_id |
*====*============*===============*
Now the models:
Products:
class Product extends Eloquent {
protected $table = 'products';
public function price_lists()
{
return $this->belongsToMany('PriceList', 'products_to_pricelists', 'price_list_id');
}
}
Price lists:
class PriceList extends Eloquent {
protected $table = 'price_lists';
public function prices()
{
return $this->hasMany('ProductPrice');
}
}
Prices:
class ProductPrice extends Eloquent {
protected $table = 'product_prices';
}
Now it's easy:
$productID = 1010;
$list_id = 1;
$theProduct = Product::find( $productID );
$theProductPriceLists = $theProduct->price_lists; // Don't use parens
$theList = Product::find( $productID )->price_lists()->where('price_lists.id', $list_id)->first(); // Here you use parens
$theListPrices = $theList->prices; // Again no parens
Laravel just manage for you the pivot-connection!
Hope that's help