Cannot validate a MultiSelect field

[dominik-eller]

• Laravel Version: 10.46
• Nova Version: 4.27
• PHP Version: 8.3
• Database Driver & Version: MYSQL
• Operating System and Version: MAC OS Sonoma 14.2.1
• Browser type and version: Safari 17.2.1
• Reproduction Repository: -/-

Description:

I am trying to make a MultiSelect field required and I ended up using something like that:

MultiSelect::make('reason')->options([
            'Option A' => 'Option A',
            'Option B' => 'Option B',
            'Option C' => 'Option C',
        ])->rules('required', 'array', 'min:1'),

I also tried to use 'in:Option A,Option B,Option C' but it is not working.

I am casting the reason property to array as suggested in the documentation, but the validation message always returns "The reason field must be an array."

Detailed steps to reproduce the issue on a fresh Nova installation:

• add a MultiSelect field to a nova resource
• add a cast to array to that property
• add a validation to the field

even just using ->rules('required') is not working for MultiSelect field.

[crynobone]

The value send on the request is array as json so the correct validation rule should be json.

[dominik-eller]

Thanks for the reply. Do you have a tested / working example of a required validation for a MultiSelect field? I tried json as well before opening the issue (discussion).

[dominik-eller]

Ok I found a solution that works for me

->rules('required', 'json', function($attribute, $value, $fail) {
            $options = ['Option A', 'Option B', 'Option C'];
            $valueArray = json_decode($value);
            $containsOption = array_intersect($options, $valueArray);
            if(empty($containsOption)) {
                $fail('The selected reason should contain at least one allowed option.');
            }
        })