Question

I have a somewhat complex pricing mechanism in my application- Here are some of my business rules to set the stage (Entities are bolded):

• A Product may have unique Price Points for a given Customer, Website, or Customer Group.
• A Product can sometimes have one or more additional Options that may have their own Price Points or Price Rules.
• A Product has one Unique Addition selected by the user, which is essentially a price and an integer.

Right now, I have an EntityRepository for Price Points to essentially determine the correct price point for the base product. The same goes for the Unique Addition and the Options.

PricePointRepository

public function getThePrice($Product, $qty, $Website, $Customer = null) 
{
    //all logic to get product price for this given instance goes here. Good.
}

Controller (simplified)

public function indexAction() 
{
    $Product = $em->dostuffwithpostdata;
    $qty = POST['qty']; //inb4insecure trolls
    $Website = $em->dostuff();
    $Customer = (if user is logged in, return their object with $em, otherwise null as it is a guest or public person); // No business logic here, just understanding the request.

    $price = $em->getRepository(PricePointRepository)->getThePrice($Product,$qty,Website,$Customer);

    $Options[] = $em->dostuffwithPOSTdata;
    $optionsPrice = 0;
    //Below is some logic directly related to pricing the product. 
    foreach($Options as $option) {
        if($option->hasRule()) {
            $optionsPrice += $ruleprice; //after some other stuff of course)
        } else {
            $optionsPrice += $em->getRepository(OptionPricePoints)->getPrice($option->getID(),$qty);
        }
    }

    $uniqueAdditionPrice = $em->stuff;

    $finalprice = $price + $optionsPrice + $uniqueAdditionPrice; //This is logic related to how I price this type of product!
    $unitprice = $finalprice / $qty;

    //twig stuff to render and show $finalprice, $unitprice, $uniqueAdditionPrice
}

That’s just for the product page. What happens when I get to the cart, saving the order, etc, when this logic needs to be reused. As you can see, I use Doctrine throughout to pull data based on my business logic in the repository classes.

I gladly welcome urdoingitwrong answers, because I really do think this is wrong. How do I go about fixing this? Something beautiful would be a service that essentially goes like this:

$pricer = getPricerService->Pricer($Entities,$postdata,$etc);
$unitPrice = $pricer->getUnitPrice();
$totalPrice = $pricer->getTotalPrice();
$optionsPrice = $pricer->getOptionsPrice();

But I have no idea how to go about doing that inside of Symfony/Doctrine, especially the way Doctrine and Repositories are accessed in Controllers.

Answer 1

You’re correct that you should have all your re-usable business logic farmed off to a service so that different controllers can re-use the code.

Have you checked out the “how to create a service” documentation:

Service Container Documentation

I’ll give you the speed run-down though.

In config.yml you need to define your service:

services:
    pricing_service:
        class: Acme\ProductBundle\Service\PricingService
        arguments: [@doctrine]

Then you just need to make a bog standard PHP class to represent your service:

namespace Acme\ProductBundle\Service;

class PricingService {

    private $doctrine;        

    function __construct($doctrine) {
        $this->doctrine = $doctrine; // Note that this was injected using the arguments in the config.yml
    }

    // Now the rest of your functions go here such as "getUnitPrice" etc etc.
}

Lastly to get your service from a controller you just need to do:

$pricingService = $this->get('pricing_service');

There are other ways you can modularise the service such as not dumping all your services into config.yml but all of that is explained in the documentation. Also note that you can inject any other service you wish into your service so if you need stuff like arguments: [@doctrine, @security.context, @validator] you can do all that stuff or even: [@my_other_service].

I suspect from your other question on injecting the EntityManager you may have already gleamed this was the way to go though!

Hopefully this was still useful to you!