什么是一个好的秘密密钥，以及如何在节点中存储它。js /表达应用程序吗?

Firstly, what's a good method of generating a secret key? I should punch in a lot of random keys on my keyboard to generate one, but there must be a better solution to this. Explain the way to generate a very good key.Firstly, what's a good method of generating a s