FactorioBot

FactorioBot is a Telegram Bot that uses Ansible to spin up / down a headless Factorio server on demand.

Why?

Multliplayer Factorio is a great time, but there are a few drawbacks to locally hosting a game that friends connect to:

• The host needs a fast, low-latency, and reliable internet connection to prevent gameplay issues
  • Example: operating vehicles like cars in the game, which have noticeable control lag when connecting to a friend's instance
• In a traditional peer-to-peer hosting case, the server can't be "left on" for others to connect as they have time
  • If you're hosting a game as a player, your player stays logged in which means the server continues to advance the game state. This gets...problematic with aggressive biter game scenarios

Luckily, Factorio has a wonderful headless version of the server available. While it's easy enough to get this running on some at-home equipment, you still run into the network requirements listed above.

So -- to the cloud! There are some great community projects, including the wonderful factorio.zone for quickly spinning up a cloud server. I thought it would be fun to try a version of that on my own, controlled by a bot. This way we can use a beefy virtual server for the game, but make sure we're only running it when we need to.

For an example of cost savings with the current server config (4GB RAM, 2 vCPUs, 80GB storage)

• monthly cost: $20
• 12 hours per week for 4 weeks: $1.44

Plus, the actual server creation doesn't take too long. From my testing, the full process to start a DigitalOcean VPS, install Factorio, copy over a save file, register a service, and boot the server takes around 2 minutes end-to-end.

Installation

FactorioBot uses Ansible to create, configure, and destroy server instances. The Telegram interaction is handled by pyTelegramBotAPI. The ansible host and bot need to be run on a box wtih a persistent internet connection. I use a LXC container in my own infrastructure, but it would probably run just fine on a Raspberry Pi or a cheap VPS instance (Vultr has some that start at $2.50 / month).

Getting started

• Clone this repo on the server that's going to run everything
  • make a copy of config_example.py and rename it to config.py for your own configs
• Create a virtual environment (optional) and install python dependencies (required): pip install -r requirements.txt
• Run factorio_downloader.py to grab the latest version of the factorio server. you might want to update the server version in config.py if you want a specific version

Ansible

• Install ansible using the instructions here. On Ubuntu:

$ sudo apt update
$ sudo apt install software-properties-common
$ sudo apt-add-repository --yes --update ppa:ansible/ansible
$ sudo apt install ansible

• Update /etc/ansible/config.cfg and set host_key_checking = False. This is needed to keep the server setup playbook interaction-free since we run that in the background without any user input.

DigitalOcean

• Create a DigitalOcean API key and add it to config.py
• Setup ssh keys: ansible uses key-based SSH to copy files and provision the VPS
  • create an ssh key on the host running the files
  • Add the ssh key to the digitalocean dashboard (Settings > Security > SSH keys section)
  • Query the digitalocean API to get the numeric key ID, e.g.,: curl -X GET -H "Content-Type: application/json" -H "Authorization: Bearer your-digitalocean-api-token" "https://api.digitalocean.com/v2/account/keys"
  • Update ansible_vars.yml to include the appropriate numeric key ID(s)
  • note: the ansible script doesn't pause for input, so make sure to source ssh keys using ssh-add / keychain / etc.

Telegram

• Talk to @botfather to create a telegram bot; follow the prompts
  • Save your API key somewhere secret
  • Update config.py to include your bot API key
• I recommend adding your bot to a group chat if needed, and then interacting with botfather to disable group adds if you want to keep your bot relatively private

Running

• Run bot.py, or use the included factorio-bot.service to set up a system service. You probably shouldn't run this as root like I did

alternatives considered / things for the future

• Initially I was thinking of using the DigitalOcean API directly and re-creating a new VPS based on a saved VM snapshot rather than from scratch each time. After some investigation of this approach I realized the thing we're doing here (copying some files and unzipipng a binary) are low-lift enough that they don't seem worth saving to a snapshot image
• Ideally we would support a range of possible VPS providers (made easier with Ansible due to a variety of provider-specific playbooks)
• This project doesn't support Factorio mods at all