Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Environment Variables

1. It seems that Docker reads neither /etc/profile nor /etc/environment for environment variables. For more details, please refer to the issue setting environment variables in a docker container #25388 on GitHub.

2. You can create environment variables for the current user using the command ENV. And you can also manually export environment variables in a init script once the container is started.

3. There is an option in JupyterHub to keep env virables from the JupyterHub process for JupyterLab processes.

Environment Variables in Entrypoint

The exec form of ENTRYPOINT does not invoke a command shell, unlike the shell form. This means that normal shell processing does not happen for exec form. For example, ENTRYPOINT [ "echo", "$HOME" ] will not do variable substitution on $HOME. If you want shell processing then either use the shell form or execute a shell directly, e.g., ENTRYPOINT [ "sh", "-c", "echo", "$HOME" ]. When using the exec form and executing a shell directly, as in the case for the shell form, it is the shell that is doing the environment variable expansion, not docker.