Sample code to get the current date, day of the week, and current time in Swift4.1.
You can get it as a string of the following format.

Thu, Apr 03, 2018
19:03:34

Here is the sample code to get it in the form shown above.

If you use Calendar.current, there is a possibility that you will get it in Japanese calendar (Heisei 00 year) depending on the setting (you want 2018/04/03, but 30/04/03 comes back), so it is better to get it in Gregorian calendar.
On the other hand, if you want a Japanese calendar, there is a way to get a Japanese calendar.

This site is detailed.
Swift 3 の日時操作チートシート

Other sites that I found helpful
Swift3での日時に関する処理
【Swift3】現在時刻の取得とDataFormatterでの文字列化