Authenticating your Command Bus

gistfile1.txt

<?php

class AddStudentGradeToCourseCommand {
    public $studentId;
    public $courseId;
    public $grade;
 
    public function __construct($studentId, $courseId, $grade)
    {
        $this->studentId = $studentId;
        $this->courseId = $courseId;
        $this->grade = $grade;
    }
}

gistfile2.txt

<?php

// Given a AddStudentGradeToCourseCommand we handle it by registering
// the new grade
use Acme\Grades\GradesRepository;
use Laracasts\Commander\Events\DispatchableTrait;
 
class AddStudentGradeToCourseHandler implements Handler {
 
    use DispatchableTrait;
 
    protected $grades;
 
    public function __construct(GradesRepository $grades)
    {
        $this->repo = $grades;
    }
 
    // We handle the adding of a new grade, the Grade::register() method
    // will raise a couple of events such that we can easily notify
    // students about their grades
    public function handle(AddStudentGradeToCourseCommand $command)
    {
        $grade = Grade::register($command->studentId, $command->courseId, $command->grade);
 
        $this->repo->save($grade);
 
        $this->dispatchEventsFor($grade);
 
        return $grade;
    }
}

gistfile3.txt

<?php

use Illuminate\Auth\AuthManager as Auth;
use Acme\Courses\CoursesRepository;
use Acme\Students\StudentsRepository;
 
class AddStudentGradeToCourseAuthenticator {
 
    protected $courses;
    protected $students;
    protected $auth;
 
    public function __construct(Auth $auth, CoursesRepository $courses, StudentsRepository $students)
    {
        $this->auth = $auth;
        $this->courses = $courses;
        $this->students = $students;
    }
 
    public function authenticate(AddStudentGradeToCourseCommand $command)
    {
        // Get the user who wants to add a grade
        $user = $this->auth->user();
 
        // Get the course from the database with its associated teachers
        $course = $this->courses->byIdWithTeachers($command->courseId);
        // Check if the given course is teached by the authenticated user
        $verification = $course->verifyCourseIsTaughtByUser($course, $user);
 
        // If any domain events were raised, dispatch them
        $this->dispatchEventsFor($course);
 
        // We throw an exception if we couldn't verify that the user teaches
        // the given course corresponding
        if (! $verification)
        {
            throw new NoPermissionException('User is not allowed to add grades to this course');
        }
    }
}

gistfile4.txt

<?php
 
// A controller using the laracasts/commander package to execute commands
class GradesController extends BaseController {
 
    public function store()
    {
        $grade = $this->execute(AddStudentGradeToCourseCommand::class);
 
        return $grade;
    }
 
}