deathbox - a dead man's switch

A monitoring service that listens to heartbeats from other devices and executes actions if no heartbeats are received after an inactive duration.

By default, sending a tweet is implemented as the action.

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Overview

I made a Youtube video briefly going over it, link is here!

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Service Instructions

Intended for VPS hosting on Linux.

git clone https://github.com/echo4eva/deathbox.git
cd deathbox
cp .env.example .env
docker compose up --build

• Change shared secret in .env, this is what the client will use to authenticate with the service. Also change or remove Twitter keys/tokens.
• Refactor code as you see fit. db.go to change the duration, or main.go to remove tweeting action.

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Client Instructions

Intended for Linux devices. Shell script runs on startup to send heartbeat to service.

Important files in this repo's /scripts directory

• deathbox.service - systemd unit to run shell script on startup
• deathbox.sh - shell script to curl the service
• deathbox.conf - config file that holds environment variables for the shell script

1. Setting up deathbox.service

mkdir -p ~/.config/systemd/user
curl https://raw.githubusercontent.com/echo4eva/deathbox/refs/heads/main/scripts/deathbox.service -o ~/.config/systemd/user/deathbox.service
systemctl --user daemon-reload
systemctl --user enable deathbox

2. Setting up deathbox.sh

mkdir -p ~/.local/bin
curl https://raw.githubusercontent.com/echo4eva/deathbox/refs/heads/main/scripts/deathbox.sh -o ~/.local/bin/deathbox
chmod +x ~/.local/bin/deathbox

3. Setting up deathbox.conf AND EDIT

curl https://raw.githubusercontent.com/echo4eva/deathbox/refs/heads/main/scripts/.deathbox.conf -o ~/.deathbox.conf

Make sure to edit the configuration:

• DEATHBOX_HOST - address of your service to send heartbeat to
• DEATHBOX_CLIENT_DEVICE - name of the client device
• DEATHBOX_SHARED_SECRET - value for authenticating client to service, should be the same

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Acknowledgements

5HT2B/heartbeat - Used as reference for infrastructure and client setup! Shoutout to an oomf for telling me about this project.