Docker starts a process inside its container as a "root" user. In some cases, this is not convenient though. For example,
initdb from PostgreSQL doesn't like to be started as root and will fail. In rultor.com, a DevOps team assistant, we're using Docker as a virtualization technology for every build we run.
Here is how we change the user inside a running container, right after it is started.
First, this is how we start a new Docker container:
There are two files in the current directory:
entry.sh is the file being executed by Docker on start, and it contains the following:
script.sh will be executed as a user
r inside the container. And this
r user will have
sudo permissions. This is exactly what all projects, managing their DevOps procedures with rultor.com, need.