Search & fill form data automatically

#Setup

We are going to start with this very simple form schema. Our goal is to automatically fill the country_region & country_subregion, based on country_name

[
    TextInput::make('country_name'),
    TextInput::make('country_region'),
    TextInput::make('country_subregion'),
]

#Search method

Lets create a new method to handle our actual search functionality.

public static function getCountryData(?string $searchTerm = null): ?array
{
    if (blank($searchTerm)) {
        return null;
    }

    try {
        $countryData = Http::baseUrl('https://restcountries.com/v3.1/name')
            ->get($searchTerm, ['fields' => 'region,subregion'])
            ->throw()
            ->json('0');

        return $countryData;
    } catch (RequestException $e) {

        return null;
    }
}

#Triggering the search

To trigger the search we are going to use a suffix action on the country_name field.

use Filament\Forms\Components\Actions\Action;

//...
TextInput::make('country_name')
    ->suffixAction(fn ($state, Set $set) =>
        Action::make('search-action')
            ->icon('heroicon-o-magnifying-glass')
            ->action(function () use ($state, $set) {
                $countryData = static::getCountryData($state);

                $set('country_region', $countryData['region'] ?? null);
                $set('country_subregion', $countryData['subregion'] ?? null);
            })
        ),