Tiles.php

<?php

declare(strict_types=1);

namespace App\Http\Controllers\Services;

use App\Models\Country;
use Illuminate\Http\Response;
use Illuminate\Support\Facades\DB;
use App\Http\Controllers\Controller;
use ShabuShabu\PostGIS\Expressions\As;
use Tpetry\QueryExpressions\Language\Alias;
use ShabuShabu\PostGIS\Expressions\Simplify;
use ShabuShabu\PostGIS\Expressions\Transform;
use ShabuShabu\PostGIS\Expressions\TileEnvelope;
use Symfony\Component\HttpFoundation\StreamedResponse;

class CountryTiles extends Controller
{
    public function __invoke(int $z, int $x, int $y): StreamedResponse
    {
        $stream = DB::query()
            ->withExpression(
                'mvtgeom',
                DB::query()
                    ->select([
                        new Alias(
                            new As\MvtGeom(
                                new Transform('t.geom', 3857),
                                new TileEnvelope($z, $x, $y),
                            ),
                            'geom',
                        ),
                        't.id',
                        't.name',
                    ])
                    ->from(
                        Country::query()->select([
                            new Alias(new Simplify('geom', 0.1), 'geom'),
                            'id',
                            'name',
                        ]),
                        't'
                    )
            )
            ->select(new Alias(new As\MVT('mvtgeom.*', 'countries'), 'pbf'))
            ->from('mvtgeom')
            ->value('pbf');

        abort_unless(is_resource($stream), Response::HTTP_NO_CONTENT);

        defer(static fn () => fclose($stream));

        return response()->stream(function () use ($stream) {
            while (! feof($stream) && connection_status() === 0) {
                echo fread($stream, 8192);
                ob_flush();
                flush();
            }
        }, Response::HTTP_OK, [
            'Content-Type' => 'application/vnd.mapbox-vector-tile',
        ]);
    }
}