Is there a need to abstract services by creating a "container" [closed] - php

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I am currently working on a personal project and i have implemented service layers. I prefer to store services independently so i don't have a large library within one file. Brief Example of File Structure below
services/
user/
authentication
login
logout
registration
news/
articles
article
I know a few people who implement a userService class that will group everything that i currently have. I prefer my method to save time in future edits + i have a lot of user services/functionality so its better to keep it separate. I was recently advised to implement a userService class in the root of my services folder and use it to call/execute the services needed within the application. Below is my example/understanding
<?php
/**
*-----------------------------------------------------------------
*
* USER SERVICE CLASS
*
* Simplifies Service Usage Within Application
*
*/
namespace Service;
use \Helper\ServiceAccess;
class UserService extends ServiceAccess {
// Define Service Prefix Key
protected $prefix = 'user/';
}
///////////////////////////////////////////////////////////////////
// Separate File ( Helper Function )
///////////////////////////////////////////////////////////////////
/**
*-----------------------------------------------------------------
*
* SERVICE ACCESS LAYER
*
* Used to Simplify the Process of Executing Services, and Grouping
* Alerts For Simple Front-end Error Messages
*
*/
namespace Helper;
class ServiceAccess extends Base {
public $dependencies = ['factory'];
// Default Service Prefix
protected $prefix = '';
// Alert Container Used By Controller to Set UI Alerts
protected $alerts = [
'errors' => [],
'info' => [],
'success' => [],
'warning' => []
];
/**
* Service Execution Method
*
* Used Within Parent Service Classes Such as UserServices
* TournamentServices
* etc.
*
* #param string $key Refers to the Factory Key ( Excluding Prefix )
* #param mixed $input Any Type of Input to Be Passed to Execute Method of Child Service
*/
public function execute($key, $input = []) {
// Create Service Class Via Factory - Call Execute Method Within Service
$service = $this->factory->make($this->prefix . $key);
$execute = $service->execute($input);
// Get & Merge Alerts From Service
$this->setAlerts($service);
// Return Result From Service Execution
return $execute;
}
/**
* Set Alerts
*
* #param array $alerts Front-End User Alerts Defined By Services
*/
private function setAlerts($service) {
$this->alerts = [
'errors' => array_merge($this->alerts['errors'], (array) $service->get('errors')),
'info' => array_merge($this->alerts['info'], (array) $service->get('info')),
'success' => array_merge($this->alerts['success'], (array) $service->get('success')),
'warning' => array_merge($this->alerts['warning'], (array) $service->get('warning'))
];
}
}
CONTROLLER EXAMPLE
<?php
/**
*-----------------------------------------------------------------
*
* LOGIN CONTROLLER
*
*/
namespace Controller\www;
use \Helper\Controller;
class Login extends Controller {
public $dependencies = ['arena', 'login', 'notification', 'site', 'userservice'];
/**
* Login
*
* Login Runs Through Various Checks Including If User is Banned, Account is Locked,
* or Forgot Password Request Is Active. Then the Entered Password is Matched & if Valid
* User is Logged In
*/
public function index() {
// User Already Logged In Redirect
$this->user->get('id') ? $this->redirect->home() : '';
/**
* User Login
*
* If Successful, Login User, Redirect Home
* Else Set Error Alerts
*/
if ($this->form->post('login')) {
// Define and Sanitize Post Data
$input = $this->input->get(['username', 'password']);
// Execute Login Service Layer - Define Flash Alerts
$login = $this->userservice->execute('login', $input);
$this->alerts($this->userservice->get('alerts'));
// Redirect Home on Successful Login
$login === true ? $this->redirect->home() : '';
}
}
}
The execute method within the ServiceAccess class is what i was advised to do the rest i added for my user error handling. My questions are as follows
Why is this better than calling the services directly within the application?
It simplified the execution of the services/setting of alerts within my controllers ( turned ~15 lines of code into 4 lines within controller ) BUT i have services like user/transactions ( Handles credit/debit of user account ) and they have separate methods that need to be used. So i am wondering if it is the UserService Class or my transaction class that needs to be updated. I was thinking of defining an execution method within transaction and just passing a key within the input to define the type of transaction being used.
Is this the best route to go about accessing/implementing services within my application?

Answer 1

The purpose of abstraction is to manage underlying complexity. If the overall complexity of the system is reduced because of an additional layer, do it. If not, reconsider. Every layer in the architecture should have a purpose for being there. And this purpose must be communicated (documented) to the developers, otherwise everyone would just be stabbing in the dark.
A good way to plan your architecture is to draw architectural diagrams and assign roles to each layer. Each layer may be a single or a collection of classes. If you struggle to find a good, clean role for a particular layer, you may not need that layer after all.
I know you're using an MVC pattern in your architecture, but that does not constitute the entire architecture, just the broad approach. Think about the consumption and execution of your services and the various layers. Think about the layers you want in your architecture. Would a UserService class make sense in your architecture? What layer does it belong to? What is the role of that layer? Sometimes you want an additional abstraction layer to reduce duplicate code - like you seem to have achieved in your case; sometimes you simply want to do it the simple, intuitive way rather than over-complicate things.
Every architectural layer, every pattern, every abstraction can be well applied or badly abused. Does adding such a layer confuse you or other developers in the team? If it does, take it out. The application of every layer (abstraction) should be elegant and intuitive - it should make everyone else in the team go "Oh yea, this is smart." But if you end up in a situation where developers are unsure how to extend/maintain the code, it becomes counter-productive.
Without a good understanding of the intent of the entire application and the background of the developers (you), it is impossible to make a good choice or give good advice. So while I understand you're asking for a best practice - in essence, "how much abstraction should we apply in our architecture/framework?", there are really no correct answers. It depends on too many things - developer preference and even coding style included. Some would even say that MVC is the wrong thing to do on the server-side.
To conclude: I can't give you a direct "Yes" or "No" answer. And I don't think anyone can. The only advice anyone can give for an architectural framework: stay DRY but avoid over-engineering.