How to set a maximum per page in laravel dynamically? - laravel

Question

I have a Products class that looks for these paginated items, but in the front end I allow the user to define how many items he wants to display per page (10, 30, 50, 100) the problem is that if someone passes 1000, the api returns 1000 records per page.
How can I validate this for all controllers and models dynamically?
I could do this "easily" by validating each request ('limit') on each controller, but it would not be practical, how can I do that?
public function index(Request $request)
{
$perPage = $request->input('limit'); // User input
$sort = 'global_performance';
$descending = 'desc';
$products = Product::where('status', 1)
->orderBy($sort, $descending)
->paginate($perPage); //
return $products;
}

Answer 1

You can validate the limit like this:
public function index(Request $request)
{
$this->validate($request, [
'limit' => ['required', 'integer', Rule::in([10, 30, 50, 100])]
]);
$perPage = $request->input('limit'); // User input
$sort = 'global_performance';
$descending = 'desc';
$products = Product::where('status', 1)
->orderBy($sort, $descending)
->paginate($perPage); //
return $products;
}
Now, add following line in just before controller class:
use Illuminate\Validation\Rule;
Update
More dynamic way might be creating custom request class like this:
Run following command to create a new form request class:
php artisan make:request PaginateRequest
This will create PaginateRequest class at App\Http\Requests directory like this:
<?php
namespace App\Http\Requests;
use Illuminate\Foundation\Http\FormRequest;
class PaginateRequest extends FormRequest
{
/**
* Determine if the user is authorized to make this request.
*
* #return bool
*/
public function authorize()
{
return false;
}
/**
* Get the validation rules that apply to the request.
*
* #return array
*/
public function rules()
{
return [
//
];
}
}
Now change this class into following:
<?php
namespace App\Http\Requests;
use Illuminate\Validation\Rule;
use Illuminate\Foundation\Http\FormRequest;
class PaginateRequest extends FormRequest
{
/**
* Determine if the user is authorized to make this request.
*
* #return bool
*/
public function authorize()
{
return true;
}
/**
* Get the validation rules that apply to the request.
*
* #return array
*/
public function rules()
{
return [
'limit' => ['required', 'integer', Rule::in([10, 30, 50, 100])]
];
}
}
After this, you can use in controller function by adding it as function parameter.
public function index(PaginateRequest $request)
{
$perPage = $request->input('limit'); // User input
$sort = 'global_performance';
$descending = 'desc';
$products = Product::where('status', 1)
->orderBy($sort, $descending)
->paginate($perPage); //
return $products;
}
Please don't forget to import it just before controller class like this:
use App\Http\Requests\PaginateRequest;
In this way, You can use this request class everywhere you need.
You can see more at documentation here: https://laravel.com/docs/5.8/validation

Answer 2

You could easily create a middleware. Apply it simply from kernel to each and every route or make a group in your route file to apply it to selective routes.
Inside the middleware just check the limit, if empty or more than the max limit you want let's say 100, make it 100 like so:
$limit = $request->input('limit');
if (empty($limit) || ($limit > 100)) {
$request['limit'] = 100;
}
wouldn't that work?
Here is link for middlewares in Laravel.