Container module incorrectly shows "Systemd" in ubuntu:20.04 Docker container

[christoph-blessing]

Current Behavior

The container module shows "Systemd" instead of "Docker" if inside a container created from the ubuntu:20.04 Docker image.

Expected Behavior

It should show "Docker" if inside a Docker container.

Additional context/Screenshots

The container module checks if the path /run/systemd/container exists to determine if it is a Systemd container. For some reason the above mentioned path exists in the mentioned image.

Possible Solution

A relatively simple fix would be to move the check for "Docker" before the one for "Systemd". Currently the Docker check comes after the Systemd check.

Environment

• Starship version: 1.5.4
• zsh version: zsh 5.8 (x86_64-ubuntu-linux-gnu)
• Operating system: Ubuntu 20.04
• Terminal emulator:
• Git Commit Hash: d420a63
• Branch/Tag: v1.5.4
• Rust Version: rustc 1.59.0 (9d1b2106e 2022-02-23)
• Rust channel: release
• Build Time: 2022-03-24 19:18:47 +00:00

Relevant Shell Configuration

<unknown config>

Starship Configuration

[aws]
disabled = true

[container]
format = "[$symbol]($style) "

[younes-io]

I would like to work on this issue

[younes-io]

The .dockerenv file was used by the deprecated LXC driver (LXC support has been removed). So, relying on this file may be an issue in the future.

Apparently, the safest way to determine if a process is running inside Docker or not is cat /proc/1/cgroup. If it's running inside Docker, the result will have /docker; so we could use something like grep -cim1 "/docker" /proc/1/cgroup.

[michel-slm]

This also happens when running under podman, and also for Ubuntu 22.04.

[jeka]

Actually, according to the description of the module the variable $name should contain the container name, not the container engine.
Yes, it shows currently Systemd inside podman container, but even if it is showing Podman or Docker or whatever else is useless info. People usually know what container engine they are using.
Its better to return info as described - the container name which is in most cases is the hostname as seen within the container

[khuongduybui]

on WSL(v2) now when SystemD is natively supported and enabled, container always show [🔴 Systemd].