Installing Tailscale via Docker Image

#!/bin/sh

# Script to check if Tailscale Docker image is installed
# and update it if needed using Watchtower.

# Temporary files for storing results
TAILSCALE_IMAGE_RESULT="/var/tmp/tailscale_image_result"
TAILSCALE_UPDATE_RESULT="/var/tmp/tailscale_update_result"

# Docker command for running Tailscale container
TAILSCALE_DOCKER_IMAGE="docker run -d \
    --name=docker-tailscaled \
    -v /storage/.config/dockers/tailscale/var/lib:/var/lib \
    -v /dev/net/tun:/dev/net/tun \
    --network=host \
    --privileged \
    --restart unless-stopped \
    tailscale/tailscale tailscaled"

# Docker command for using Watchtower to update the Tailscale container
WATCHTOWER_DOCKER_IMAGE="docker run --rm \
    -v /var/run/docker.sock:/var/run/docker.sock \
    containrrr/watchtower --run-once docker-tailscaled"

# 1. Clean up old Docker images (optional)
# Uncomment the line below to enable cleaning up old images
# docker system prune -f

# 2. Check if Tailscale container is already running
docker ps -a | grep -c "docker-tailscaled" > $TAILSCALE_IMAGE_RESULT

# 3. Read the result into a variable
IMAGE_RESULT=$(cat $TAILSCALE_IMAGE_RESULT)

# 4. If Tailscale is not installed (IMAGE_RESULT == 0), install it
if [ "$IMAGE_RESULT" -eq 0 ]; then
    echo "Tailscale container not found, installing..."
    eval $TAILSCALE_DOCKER_IMAGE
else
    echo "Tailscale container is already installed."
fi

# 5. Check if an update is required for Tailscale
docker exec docker-tailscaled tailscale update | grep -c "no update needed" > $TAILSCALE_UPDATE_RESULT

# 6. Read the update result into a variable
UPDATE_RESULT=$(cat $TAILSCALE_UPDATE_RESULT)

# 7. If update is required, run Watchtower to update the container
if [ "$UPDATE_RESULT" -eq 0 ]; then
    echo "Update required for Tailscale. Running Watchtower to update..."
    eval $WATCHTOWER_DOCKER_IMAGE
else
    echo "Tailscale is up to date."
fi