Run DDNS updater as a systemd service

.env

RESOLVER_ADDRESS=1.1.1.1:53
BACKUP_PERIOD=24h
LISTENING_ADDRESS=:8092
DATADIR=data
BACKUP_DIRECTORY=backups
TZ=Europe/London

build.sh

#!/bin/bash

# Build ddns-updater (optional: pass release tag, e.g. v2.6.0)

(
        cd src
        if [[ -n "$1" ]]; then
                git fetch
                git checkout "$1"
        fi
        go build -o ../ddns-updater cmd/updater/main.go
)

ddns-updater.service

[Unit]
Description=Update DNS records periodically
After=network.target
Wants=network-online.target

[Service]
Restart=always
Type=simple
ExecStart=/home/ddns-updater/ddns-updater
WorkingDirectory=/home/ddns-updater
User=ddns-updater
Group=ddns-updater
EnvironmentFile=/home/ddns-updater/.env

[Install]
WantedBy=multi-user.target

setup.sh

#!/bin/bash

# Add ddns-updater user
sudo adduser ddns-updater

# Create data and backups directory
sudo mkdir /home/ddns-updater/{data,backups}
sudo touch /home/ddns-updater/data/config.json
sudo cp {.env,build.sh} /home/ddns-updater/
sudo chown -R ddns-updater:ddns-updater /home/ddns-updater/{data,backups,.env}

# Become ddns-updater user
sudo su - ddns-updater

# Clone source code
git clone https://github.com/qdm12/ddns-updater.git src

# Build version 2.6.0
./build.sh v2.6.0

# Test that it works
export $(cat .env | xargs)
./ddns-updater

# Go back to originating user
logout

# Create systemd service
sudo cp ddns-updater.service /etc/systemd/system/
sudo systemctl start ddns-updater.service
sudo systemctl enable ddns-updater.service

# Final check
sudo journalctl -u ddns-updater.service