A Laravel class for content negotiation in JSON or flat-file (CSV/XLS(X)/etc)

Negotiable.php

<?php

namespace App\Http\Responses;

use Closure;
use Illuminate\Contracts\Support\Responsable;
use Illuminate\Database\Eloquent\Builder as EloquentBuilder;
use Illuminate\Database\Eloquent\Relations\Relation;
use Illuminate\Database\Query\Builder;
use Illuminate\Http\Resources\Json\JsonResource;
use InvalidArgumentException;
use Maatwebsite\Excel\Concerns\FromQuery;
use Spatie\QueryBuilder\QueryBuilder;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\Exception\NotAcceptableHttpException;

/**
 * Implements an HTTP-compliant Content Negotiation response.
 *
 * Given a Laravel "JsonResource" transformer and a Laravel-Excel "Exporter",
 * the incoming request's `Accept` header is used to choose the appropriate response
 * format.
 *
 * In the event the incoming request indicates that any response type is accepted
 * (using `*\/*`), JSON is used as the default. If the requested type is not supported,
 * a spec-compliant 406 response is returned.
 *
 * This class is partially inspired by the Ruby on Rails `ActionController#respond_to` method.
 *
 * @package App\Http\Responses
 */
class Negotiable implements Responsable
{
    protected const SUPPORTED_DOWNLOAD_TYPES = [
        'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' => \Maatwebsite\Excel\Excel::XLSX,
        'application/vnd.ms-excel' => \Maatwebsite\Excel\Excel::XLS,
        'application/vnd.oasis.opendocument.spreadsheet' => \Maatwebsite\Excel\Excel::ODS,
        'text/csv' => \Maatwebsite\Excel\Excel::CSV,
    ];

    public function __construct(
        protected Builder|EloquentBuilder|Relation|QueryBuilder $query,
        protected string $jsonResource,
        protected string $exportClass,
        protected null|array|Closure $additionalData = null,
        protected string $name = 'data',
    )
    {
        if (!is_a($jsonResource, JsonResource::class, allow_string: true)) {
            throw new InvalidArgumentException("$jsonResource must be a valid JsonResource");
        }

        if (!is_a($exportClass, FromQuery::class, allow_string: true)) {
            throw new InvalidArgumentException("$exportClass must be a valid Laravel-Excel Exporter");
        }
    }

    /**
     * Create an HTTP response that represents the object.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function toResponse($request): Response
    {
        // Check for JSON
        if ($request->accepts('application/json')) {
            return tap(($this->jsonResource)::collection($this->query->get()), function (JsonResource $r) {
                if ($this->additionalData) {
                    $r->additional(value($this->additionalData));
                }
            })->toResponse($request);
        }

        // Check for any supported flat-file type
        if (($mimeType = $request->prefers(array_keys(static::SUPPORTED_DOWNLOAD_TYPES)))) {
            $type = static::SUPPORTED_DOWNLOAD_TYPES[$mimeType];
            $name = $this->name . '.' . strtolower($type);

            return (new ($this->exportClass)($this->query))
                ->download(
                    $name,
                    $type,
                    [
                        'Content-Type' => $mimeType,
                    ],
                );
        }

        throw new NotAcceptableHttpException('Unrecognized content type');
    }
}