laravel_demo/app/Http/Controllers/data_controller.php

<?php

namespace App\Http\Controllers;

use Illuminate\Support\Facades\Storage;
use Illuminate\Http\Request;

class data_controller extends Controller {
	public function index() {
		$files = Storage::files("test_data");
		$rows = [];

		foreach ($files as $k => $v) {
			$data = json_decode(Storage::get($v));
			$rows[] = [
				// "file" => $v,
				"email" => $data->email,
				"message" => $data->message
			];
		}

		return $rows;

		return view("data", ["rows"]);
	}
}