Have you ever wanted to generate a password using the openssl passwd command, but didn't want the prompt?

I encountered this problem when I was writing an Ansible role for setting up Nginx basic auth. I didn't want the prompt since I had no way for ansible to handle that gracefully. After some Googling, and some man page grepping, I found the answer.

You can generate a password without a prompt by piping text into openssl and passing a new flag. For example:

echo "password" | openssl passwd -apr1 -stdin

This will echo to stdout. This way you can write a script or something instead of having to use the prompt to type in the password.

In my case of generating a basic auth password, I had to append the output to the /etc/nginx/.htpasswd file. That was done using the following command:

echo "password" | openssl passwd -apr1 -stdin >> /etc/nginx/.htpasswd

There ya go. It's that easy. I have actually used this trick a couple times for generating passwords and piping to pbcopy (the clipboard) on my mac.

Pretty useful stuff!