Slipway

An easier way to use containers for development on Linux. It automatically maps credentials, sets up things such as the clipboard, and corrects permission issues which arise from developing with containers natively.

What this tool does

• Automatically maps ssh credentials into the container
• Automatically maps GPG
• Inspects the image for volumes and will correct any permission issues. For example if you're using npm and you want the cache to be persisted between restarts you can add the following to your image:

VOLUME $HOME/.npm

Since docker will create the directory with root as the owner slipway will correct it automatically.

• Detects X11 support and will map it into the container (clipboard integration).
• Handles open calls (e.g., open in browser on the host) via unix sockets.
• Maps your ~/workspace directory into the container (can be overriden).
• Sets the timezone to match the host
• Sets your git config to match the host
• Maps credentials files for certain package managers to the container (yarn, cargo, etc).
• sets up correct uid mappings on podman.

Requirements

• Linux OS
• Python 3.7+
• Podman (rootless only)

Getting Started

Install slipway:

python3 -m pip install slipway

Run an example image:

slipway start aghost7/nodejs-dev:focal-carbon

Configuration

The start command line options can be specified in a configuration file under ~/.config/slipway.yaml.

pull: true
pull_daily: true
runtime: podman
alias:
  devops:
    image: aghost7/devops:focal
    network: slirp4netns
    environment:
    - AWS_ACCESS_KEY_ID

You can then use your devops alias in place of the image name:

slipway start devops

Optional GnuPG (GPG) Support

On your host, you will need to have gpg configured with the daemon running. Slipway will detect that gpg is running and will automatically create a bind mount (volume) to map the socket file into the container.

Enable gpg signing git commits:

git config --global commit.gpgSign true

If you want to always sign tags:

git config --global tag.forceSignAnnotated true

Since we want gnupg to be used from the terminal interface, we need to change the configuration under ~/.gnupg/gpg.conf:

use-agent
pinentry-mode loopback

Using rootless containers

Slipway supports podman, which is an alternative implementation to docker that has much better security. There are additional steps to setting this up, which is why it isn't the default.

Start by installing podman.

Setup the registry configuration:

mkdir -p ~/.config/containers
echo 'unqualified-search-registries = ["docker.io"]' > ~/.config/containers/registries.conf

Install some additional dependencies:

sudo apt-get install -y fuse-overlayfs slirp4netns

Grant your user some [subuids][subuids]/[subgids][subgids]:

echo "$USER:100000:600000" | sudo tee -a /etc/subuid
echo "$USER:100000:600000" | sudo tee -a /etc/subgid
podman system migrate

And then you can run your containers with podman instead!

slipway start --runtime podman aghost7/nvim:focal

I can't use networking tools (nmap, traceroute, etc) with rootless containers

This is actually because slipway defaults to host-based networking. When using rootless containers, you need to change the network used to slirp4netns.

slipway start --network slirp4netns aghost7/devops:focal

Developing

Requirements:

• python 3
• poetry

Install dependencies:

poetry install

Run tests:

poetry run pytest