Laravel 5 route protection - laravel

Assume we´ve got a User and Conversation model with a many-to-many relation.
class User extends Model ... {
public function conversations()
{
return $this->belongsToMany('App\Conversation');
}
}
class Conversation extends Model {
public function users()
{
return $this->belongsToMany('App\User');
}
}
Besides authentication (logging in) which comes out of the box with laravel: How can I protect a specific conversation route for it´s related users?
Which would be the most maintainable way to achieve this? Middleware? Guard? Route model binding? ... right now I´m a bit lost ...

Good question. In this case you'd be best off using Laravel's authorization features. Here are the differences:
Middleware: used to run logic based on either routes or logged in / logged out state. So, if you want to block the conversations entirely from non-logged in users, use a middleware.
Authorization (policies): not to be confused with authentication, is intended for cases where the rules to block someone is not based on route but on some other, more specific reason. These reasons can be anything from roles, to teams, entity ownership, and so on. If you wanted to hide a conversation to only those in the conversation, you can create a policy that kicks the user back to their previous page if they were not in the conversation.
Here's a quick policy you might create:
class ConversationPolicy {
public function view(User $user, Conversation $conv) {
return in_array($user->id, $conv->users->pluck('id'));
}
}
You could check your policy in a controller like the following:
if($request->user()->can('view', $conversation))
{
return view('conversation', ['conversation' => $conversation]);
}
return back()->withError('You are not authorized to view this conversation');
Just be aware you'll have to bind this policy in the AuthServiceProvider before it can be used.

Related

Laravel 8 - Global Object available throughout application (not just in view files)

In my application, users can belong to different accounts and have different roles on those accounts. To determine which account is "current" I am setting a session variable in the LoginController in the authenticated() method.
$request->session()->put('account_id', $user->accounts()->first()->id);
Then, throughout the application I am doing a simple Eloquent query to find an account by ID.
While this "works", I am basically repeating the same exact query in every single Controller, Middleware, etc. The maintainability is suffering and there are duplicate queries showing in Debugbar.
For example, in every controller I am doing:
protected $account;
public function __construct()
{
$this->middleware(function($req, $next){
$this->account = Account::find($req->session()->get('account_id'));
return $next($req);
});
}
In custom middleware and throughout the entire application, I am essentially doing the same thing - finding Account by ID stored in session.
I understand you can share variable with all views, but I need a way to share with the whole application.
I suppose much in the same way you can get the auth user with auth()->user.
What would be the way to do this in Laravel?
I would create a class to handle this logic. Making it a singleton, to ensure it is the same class you are accessing. So in a provider singleton the class you are gonna create in a second.
$this->app->singleton(AccountContext::class);
Create the class, where you can set the account in context and get it out.
class AccountContext
{
private $account;
public function getAccount()
{
return $this->account;
}
public function setAccount($account)
{
$this->account = $account;
}
}
Now set your account in the middleware.
$this->middleware(function($req, $next){
resolve(AccountContext::class)->setAccount(Account::find($req->session()->get('account_id')));
return $next($req);
});
Everywhere in your application you can now access the account, with this snippet.
resolve(AccountContext::class)->getAccount();

Create generic route-based authorization in Laravel

I'm coming from conventional PHP background and trying to create my first big project in Laravel.
I usually user User/Role/Permission to manage user permissions in my applications. It works like follows:
User has many Roles
Role has many Permissions
to make things simple, I actually used the page names as permissions, so that I check the current page name against user permissions.
That was all easy in PHP, now I am trying to implement a similar approach in Laravel. I have User, Role, Permission models, and I check if user has permission using a method in User model as follows (inspired from a Laracasts tutorial):
public function permissions()
{
return $this->roles->map->permissions->flatten()->pluck('name')->unique();
}
And in my AuthServiceProvider I added the following code:
Gate::before(function ($user, $permission){
return $user->permissions()->contains($permission);
});
So if I add some permission (for example 'add_user') to the user, I can simply do the following in the route, and it works just fine:
Route::get('/test', function () {
return 'You are authorized';
})->name('add_user')->middleware('can:add_user');
Now since I have a lot of pages, I wouldn't like to pass specific permission name to the middleware, rather find a better and more generic way.
The only way I could come up with is to use the permission name same as the route name, and create a new middleware to take care of authorization.
So In my solution I added the following middleware class:
class BeforeMiddleware
{
public function handle($request, Closure $next)
{
$route_name = $request->route()->getName();
if(!Auth::user()->permissions()->contains($route_name)) {
throw new \Exception('Not Authorized');
}
return $next($request);
}
}
Added it to Kernel.php:
protected $routeMiddleware = [
'before' => \App\Http\Middleware\BeforeMiddleware::class,
...
];
And finally changed the route to be as follows:
Route::middleware(['before'])->group(function () {
Route::get('/test', function () {
return 'You are authorized';
})->name('add_user');
});
This way I don't actually have to pass the permission name when I check the permission, and directly get it from the route name.
I have many questions about my solution: is it really a good approach? Does it have any drawbacks? Is there a better approach?
Also I preferred to use AuthServiceProvider instead of the new middleware, but I couldn't retrieve the route name from ServiceProvider scope. Can I somehow use AuthServiceProvider for a similar case?
Sorry if I made the post somehow long, but I needed to be as clear as I could.

Laravel: How can I write a policy class for API methods on a nested resource controller?

I have a many to many relationship that I'm working with between User and Task models. A user belongs to many tasks and a task belongs to many users. I have a pivot table called task_user.
In my API, I have a route defined as follows:
Route::get('/users/{user}/tasks', 'TaskUserController#all');
I want to write a policy to enforce that the currently logged in user, auth()->user, is the user being requested in the route. Basically, a user can only view their own tasks.
How can I write a policy class for the nested resource controller TaskUserController?
Nesting of your resource has nothing to do with making policies.
Make your UserPolicy.
class UserPolicy()
{
public function view(User $authorizedUser, User $user) {
return $authorizedUser->is($user);
}
}
In your controller, you can authorize the action, with the authorize() helper. Alternatively it can be executed in your form request with Auth::user()->can().
class TaskController {
public function all(User $user)) {
$this->authorize('view', $user);
return $user->tasks;
}
}

In Laravel, Where I should fire events and emails in repo or in controller?

I am using repository pattern in develop an application using laravel, my question is where I have to write code for fire events, send email or send an notification? and why?
This is really a broad question and many will come with their own opinions. In my opinion, form the context of Laravel, I would define types of my events depending on the operations.
So for example, as you mentioned email/notification events, I would like to think this way (This is a hypothetical example):
class UserController
{
public function register(Request $request, UserRepository $user)
{
if ($user = $user->register($request->all())) {
Email::send(...);
}
}
}
In this case, an email should be sent to the user after the registration so I can use an event to do the same thing within the controller for example:
class UserController
{
public function register(Request $request, UserRepository $user)
{
try {
$user = $user->register($request->all());
Event::fire('user_registered', $user);
} catch(RegistrationException $e) {
// Handle the exception
}
}
}
In this case, I think, the event dispatching should be in the controller because it's the part of my application layer to control the application flow so, email sending event should be dispatched from controller. The UserRepository should not care about your application's flow, sending email to the user is not part of your UserRepository, so that's it.
Now, think about another hypothetical example, say you've a delete method in your UserController as given below:
class UserController
{
public function delete(UserRepository $user, $id)
{
if($user->findOrFail($id)->delete()) {
Post::where('user_id', $id)->delete();
}
}
}
Well, in this case, the deletion of the user involves some domain related operations so I would rewrite the method as given below:
public function delete(UserRepository $user, $id)
{
try {
$user->delete($id);
return redirect('/users'); // show users index page
} catch (InvalidOperationException $e) {
// Handle the custom exception thrown from UserRepository
}
}
Notice that, there is no related operations took place in the delete method because I would probably fire an event inside the UserRepository because this delete action involves some other domain/business related operation and application layer should not care about it (in this case) because the deleting an user effects some other domain objects so I'll handle that event this way.
Anyways, this is just my way of thinking and it's just an opinion. Maybe in a real world situation, I could come up with a different idea so it's up to you, depending on the context you should think about it and finally there's no recommended way in Laravel, you can even use Models to fire events, so just keep it simple, make the decision depending on your context that fits well.

Controller constructor to check Auth middleware for two different guards

I have a dashboard view that shows certain contain depending on which user is viewing, whether it be an admin or just a regular user.
I can get my admins onto that page, but regular users aren't able to currently because of my middleware guard.
class DashboardController extends Controller {
public function __construct()
{
$this->middleware('auth:admin');
}
public function index()
{
return view('dashboard.index');
}
}
The following code checks on each DashboardController call for auth:admins, but I want regular users to access this too, is there a way to check the auth middleware twice like so?
$this->middleware(['auth:admin','auth']);
So ideally it will check if you're an admin or just a regular auth user.
Also on my view page, when accessing properties of an admin I'm using:
{{ Auth::user()->admin_username }}
Is this normal? I have an admin Model but I'm still accessing it via Auth::user() which feels strange to me, shouldn't it be Auth::admin()->admin_username
Accessing a particular page for users with differing roles is more suited for laravels gates and policy authorization mechanisms.
https://laravel.com/docs/5.5/authorization#writing-gates
These allow you to write fine tuned rules for each use case you have. Simple gates can be defined as closures within your application AuthServiceProvider. For example:
public function boot()
{
$this->registerPolicies();
Gate::define('access-dashboard', function ($user, $post) {
return auth()->check() && (auth()->user()->hasRole('admin') || auth()->user()->hasRole('regular'));
});
}
Then you can use the gate facade wherever necessary, for instance a controller method or constructor.
if (Gate::allows('access-dashboard', $model)) {
// The current user can access dashboard, load their data
}
Alternatively use the can or cant helpers on the user model directly.
if (auth()->user()->can('access-dashboard')) {
//
}
Of course, you can achieve similar via middleware, the advantage of using the above is you can authorize actions at specific points in your code as well as reusability.
As for for last question, as you have it written is correct.
{{ Auth::user()->admin_username }}
Auth::user() or auth()->user() simply returns the currently authenticated user, regardless of their role.
Policies will never work without auth middleware

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