laravel 5.4 herokuapp在将图像上传到谷歌硬盘时引发错误

Question

Uploading Images using google drive api and it works fine locally but throws an error on heroku
ErrorException in GoogleDriveAdapter.php line 1143: A non well formed numeric value encountered

public function store() {
    $validator = Validator::make(request()->all(), [
        'img' => 'required|image'
    ]);
    if ($validator->fails()) {
        return response()->json('err');
    } else {
        $path = request()->file('img')->store('');
        $url = Storage::url($path);
        auth()->user()->addImage($url);
        return response()->json($url);
    }
}