Laravel form request not updating nullable field

Question

I have created a PostRequest in Laravel (using php artisan make:request PostRequest ). I have three columns: title, content, and tag). The tag column is nullable. When I add some posts there is no problem, I am able to add title, content, and tag.

However, when I want to edit a post, the title and content column change but the tag column is not. How can handle this?

Controller

public function update(PostRequest $request, Post $post)
{
    $validated = $request->validated();

    Post::whereId($post->id)->update($validated);

    return redirect('/posts')->with('success', 'success');
}

PostRequest.php

public function rules()
{
    switch ($this->method()) {
        case 'POST':
        {
            return [
                'title' => 'required|max:512',
                'content' => 'required',
            ];
        }
        case 'PUT':
        case 'PATCH':
        {
            return [
                'title' => 'required|max:512',
                'content' => 'required',
            ];
        }
        default:
            break;
    }
}

Post.php (model)

protected $fillable = [
    'title',
    'content',
    'tag',
    'created_at',
];

Answer 1

You are using $request->validated() that filters your request inputs and returns only validated fields. So adding a new rule for tag will fix your issue:

return [
    'title' => 'required|max:512',
    'content' => 'required',
    'tag' => 'nullable'
];