Docker entrypoint will not prompt for my input

Question

Here's the entrypoint of my Dockerfile:

ENTRYPOINT ssh-agent bash\
           && ssh-add directory/id_rsa

If I run my docker container with docker run my_conatiner -rm, I get:

Could not open a connection to your authentication agent.

instead of being prompted to insert the private key password.

If I run, however, with ENTRYPOINT /bin/bash, and paste the two commands manually, I get prompted to insert the password for the private key.

Answer 1

Running ssh-agent bash will start a new bash with the environment variables set. But since you don't provide any input, the bash exits, together with the ssh-agent and then in the original bash, there is again no connection to your ssh-agent. With a diagram of processes how they are called:

bash
 '- ssh-agent bash
   '- bash < no input, exits cleanly
 '- ssh-add ...

What you want to do instead is to invoke ssh-agent the intended way:

ENTRYPOINT eval `ssh-agent` \
       && ssh-add directory/id_rsa