ubuntu-torrent-operator

A Juju charm that deploys and manages the BitTorrent seeding infrastructure behind torrent.ubuntu.com.

Components

The charm orchestrates three sub-components:

• Aquatic (src/aquatic.py) — a high-performance HTTP BitTorrent tracker written in Rust. It runs with an access-list allow mode so only approved torrents can announce.

• Transmission (src/transmission.py) — the BitTorrent client daemon that seeds Ubuntu ISO files. It watches a directory for new .torrent files and auto-adds them, announcing to the Aquatic tracker.

• Synchronizer (src/synchronizer.py) — a systemd timer that periodically runs src/torrent-sync.py, which rsyncs .torrent metafiles and ISO images from cdimage.ubuntu.com, feeds them to Transmission, and updates the Aquatic access list.

Data Flow

                  cdimage.ubuntu.com
                           ↓
             torrent-sync.py (every 5 min)
          runs `rsync` and manipulates files
            ↙              ↓           ↘
   .torrent files      ISO images     access-list
           ↓               ↓            |
     watch dir        download dir      |
              ↘        ↙                |
               auto-add                 |
                  ↓                     ↓
             Transmission → Aquatic tracker
                      announce
                          

Code Layout

Path	Purpose
src/charm.py	Charm entry point — wires lifecycle hooks to the three sub-components
src/aquatic.py	Aquatic tracker lifecycle
src/transmission.py	Transmission daemon lifecycle
src/synchronizer.py	Torrent-sync systemd timer lifecycle
src/torrent-sync.py	Script that downloads torrents and ISOs
src/constants.py	Shared paths and user constants

Github Actions and Charmhub

The charm is automatically built and published by the CI.

Refreshing the CHARMCRAFT_TOKEN

The CHARMCRAFT_TOKEN is what allows the CI to push the charm to charmhub. If it expires, you can refresh it with the following:

charmcraft login --export=secrets.auth --charm=ubuntu-torrent-operator  --permission=package-manage --permission=package-view --ttl=$((3600*24*365))
cat secrets.auth