Using rust_light

The rust_light image provides the minimal amount of CLI tooling and libraries needed to do the practicals. It is based on Ubuntu 22.04, with libraries installed system-wide and the Rust toolchain and associated software installed locally to the root user’s home directory (/root).

The intent is for you to layer whatever code editing environment you prefer1 on top of this using your favorite container image building mechanisms: Dockerfiles, docker commit, buildah…

Alternatively, you can just directly bind-mount the source code as done with the rust_code_server image (minus the :U bind mount flag for Podman, see bullets below) and start editing it with your local code editor on the host system, only using the container for builds and executions. Compared to the suggested rust_code_server workflow…

  • You cannot get early feedback from rust-analyzer while editing code, because it must be running inside of the container to have access to all dependencies. In general, if your code editor’s has check/build/run shortcuts or other IDE functionality, it won’t work as expected.
  • You will not experience any file permission issues inside of the container and can/should drop the :U bind mount flag when using Podman, because everything in the rust_light container runs as the root user, and root can write to any file no matter which UID/GID is the owner.
  • If you are using Docker, you will still get file permission issues outside of the container because on Linux, any file created by the root user inside of a Docker container is owned by the host root account. Podman does not suffer from this issue.2

Given that this environment is open-ended and geared towards expert container users who want to go in exotic directions, a detailed tutorial cannot be easily written, so I invite you to just e-mail the trainer if you run into any trouble while going this route, and we’ll try to figure it out together.

1

Be warned that getting X11/Wayland software to work inside of Linux containers involves a fair amount of suffering. You will make your life easier by favoring editors that run directly in the terminal (like vi and nano) or expose a web-based gui via an HTTP server (like jupyterlab and code-server).

2

Speaking from the perspective of using Docker and Podman in the conventional way, which for Docker involves a daemon with root privileges and for Podman involves a rootless setup with sub-UIDs/GIDs. If you are using more exotic setups, like rootless Docker or sudo’d Podman commands, your experience may differ.