Laravelの.envでArrayを使う方法
参考
https://laracasts.com/discuss/channels/general-discussion/return-array-from-env#reply-320641
検証環境
Laravel 5.5 LTS
.env
VARIABLE_NAME=name1,name2,name3
config/app.php
'MY_ENV_ARRAY' => array_map('trim', explode(',', env('VARIABLE_NAME')))