Validating a Unique Slug on Update in Laravel 5 - php

Question

I currently have a model that has a text field and a slug field.
I validate that the slug is unique in my form request class:
public function rules()
{
return [
'name' => 'required|min:3',
'slug' => 'required|alpha_dash|unique:questions'
];
}
This works fine on create and properly denies the creation of duplicate slugs. However on my update method, it won't let me save a record because the slug already exists. Of course the slug does exist, but it exists on the record being edited, so I would like to continue to allow it to be saved. However, it should not be able to be changed to a slug on ANOTHER record.
Here's what my update ArticlesController method looks like:
public function update(Article $article, ArticleRequest $request)
{
$article->update($request->all());
return redirect('articles');
}
Is there a way to make this work in L5?

Answer 1

Try to modify your rule like following(in form request class):
public function rules()
{
return [
'name' => 'required,min:3',
'slug' => 'required|alpha_dash|unique:categories,slug,'.$this->id')
];
}
It works for me.

Answer 2

In unique rule you may specify id you want to ignore.
You can create 2 separate request (one for create and one for update), but you can do it also this way checking if if is set(I assume your update url looks like /questions/2 ):
public function rules()
{
$rules = [
'name' => 'required|min:3',
'slug' => ['required', 'alpha_dash']
];
$rule = 'unique:questions';
$segments = $this->segments();
$id = intval(end($segments));
if ($id != 0) {
$rule .= ',slug,' . $id;
}
$rules['slug'][] = $rule;
return $rules;
}
}

Answer 3

If you must have the ability to update a slug, projects I've worked on usually require it is not editable after creation, then you can use laravel's built in rule to ignore a certain record on the table by primary key.
$rules['slug'] = "required|unique:questions,slug,{$id}";
http://laravel.com/docs/5.0/validation
see "Forcing a unique rule to ignore a given ID"

Answer 4

In EditArticleRequest:
public function $rules ()
{
$id = $this->id;
return [
'name' => 'required|min:3',
'slug' => "required|alpha_dash|unique:articles,slug,$id",
];
}

Answer 5

Here is how I do it in Laravel 5.3 in details:
1- Create a new Form Request class by executing the next command in your terminal:
php artisan make:request ArticleFormRequest
Where ArticleFormRequest is the name of the form request class. This command will create a file called ArticleFormRequest.php in app/Http/Requests directory.
2- Open that created file and remove its content then place the next content in it:
<?php
namespace App\Http\Requests;
use Illuminate\Foundation\Http\FormRequest;
use Illuminate\Http\Request;
use Illuminate\Validation\Rule;
use App\Article;
class ArticleFormRequest extends FormRequest
{
protected $rules = [
'name' => 'required|min:3',
'slug' => 'required|alpha_dash|unique:articles,slug',
];
// protected $user; // in case you want the current authenticated user
protected $request_method;
protected $id;
public function __construct(Request $request)
{
// $request->user() returns an instance of the authenticated user
// $this->user = $request->user(); // in case you want the current authenticated user
// $request->method() returns method of the request (GET, POST, PUT, DELETE, ...)
$this->request_method = strtoupper($request->method());
// segments(): Returns an array containing all of the segments for the request path
// it is important to assign the returned "segments" array to a variable first before using it, otherwise an error will occur
$segments = $request->segments();
// note this way will be valid only if "id" of the element is the last segment
$this->id = end($segments);
}
/**
* 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()
{
$rules = $this->rules;
if ($this->request_method == "POST") {
// do nothing..
} elseif (in_array($this->request_method, ["PUT", "PATCH"])) {
$article = Article::find($this->id);
if ($article) {
// forcing a unique rule to ignore a given id | https://laravel.com/docs/5.3/validation
$rules["slug"] = [
"required",
"alpha_dash",
Rule::unique("articles", "slug")->ignore($article->id, "id"),
];
// this is also can be used
// $rules['slug'] = "required|alpha_dash|unique:articles,slug,$article->id,id";
}
}
return $rules;
}
}
3- In your controller, you can use that ArticleFormRequest in store() and update() methods like this:
<?php
namespace App\Http\Controllers;
use App\Http\Requests\ArticleFormRequest;
class ArticlesController extends Controller
{
public function store(ArticleFormRequest $request)
{
// your code here..
}
public function update(ArticleFormRequest $request, $id)
{
// Your code here..
}
}

Answer 6

As already mentioned you can use the ignore feature in the validator functionality.
Just reference the id of the item you wish to ignore and make sure that when you update you use a patch request!
See more info here! http://laravel.com/docs/5.0/validation#rule-unique
protected $rules = [
'name' => 'required|min:3',
'slug' => 'required|alpha_dash|unique:questions'
];
public function rules()
{
$rules = $this->rules;
if ($this->isMethod('patch'))
{
$id = $this->articles;
$rules['slug'] = $rules['slug'].',slug,'.$id;
}
return $rules;
}