SOLID laravel examples #blog

di_violation.php

<?php

namespace App\Domain\Employee;

// this introduces a source code dependency
use App\Domain\Employee\ScreenOutput;

class Employee
{
    // this violates the dependency inversion principal because we depend on a concretion
    public function __construct(ScreenOutput $outputDevice) { 
        $this->outputDevice = $outputDevice;
    }
}

fat_controller.php

<?php

public function showWeeklyHours()
{
    $employeeId = e(Input::get('employee_id',''));
    if(!$query && $query == '') return Response::json(array(), 400);
    $hours = HoursWorked::where('active', true)
        ->where('employee_id',$employeeId)
        ->where('created_at', '>', strtototime('-1 week'))
        ->orderBy('created_at','desc')
        ->take(7)
        ->toArray();    
    // Data normalization and validation
    $returndata = [];
    foreach ($hours as $hour) {
       $returnData = [
           'date' => $hour['created_at']
           'hours' => number_format($hour['hours_worked'], 2, '.', '');
       ];
    }
    // format the data and return it 
    return Response::json(array(
        'hours' => $returnData
    ));
}

public function calculateWeeklyPay()
{
    $employeeId = e(Input::get('employee_id',''));
    if(!$query && $query == '') return Response::json(array(), 400);
    $hours = HoursWorked::where('active', true)
        ->where('employee_id',$employeeId)
        ->where('created_at', '>', strtototime('-1 week'))
        ->orderBy('created_at','desc')
        ->take(7)
        ->toArray();    
    $employee = Employee::find($employeeId);
    // Calculation
    $wage = 0;
    foreach ($hours as $hour) {
        $wage += $employee->hourlyWage * $hour['hours_worked'];
    }
    // format the data and return it 
    return Response::json(array(
        'week_starting' => strtototime('-1 week')
        'wage' => $wage
    ));
}

liskov_principal_violation.php

<?php

class PayCalculator { }

// the below class would be in a different file!
class PermanentEmployeePayCalculator  extends PayCalculator
{
    public function calculatePay(int $employeeId) { ... }
}

// the below class would be in a different file!
class TemporaryEmployeePayCalculator extends PayCalculator
{
    public function calculatePay(int $employeeId, float $hourlyWage) { ... }
}

liskov_substitution.php

<?php

namespace App\Domain\Employee;

class PermanentEmployeePayCalculator  implements PayCalculatorInterface
{
    public function calculatePay(int $employeeId) { ... }
}

// the below class would be in a different file!
class TemporaryEmployeePayCalculator implements PayCalculatorInterface
{
    public function calculatePay(int $employeeId) { ... }
}

single_responsibility_example.php

<?php

namespace App\Domain\Employee;

class PayCalculator 
{
    public function calculatePay(int $employeeId) { ... }
}