Often your project will require some secret keys or tokens - for instance, API keys or database authentication information. Learn how to safely and easily deploy secrets to now, and how to expose them as environment variables that your applications can load without making them public to the world.
Deploy with env variable:
now -e GREETING=Hello
now -e GREETING=Hello -e NAME=Egghead
But sometime you might don‘t know the variable be public. You want to make it secret.
now secret add greeting Hello
now secret add name Egghead
Then you can make a script to deploy:
now -e GREETING=@greeting -e NAME=@name
List your all secrets:
now secrets ls
Remove recret:
now secret remove name
[Now] Configure secrets and environment variables with Zeit’s Now
原文：http://www.cnblogs.com/Answer1215/p/6193131.html