A bitbar app that starts and stops a DO droplet

ssh_config

Host workspace
	User steven
	ForwardAgent yes
	ControlPersist 300
	HostName 64.225.89.72
	StrictHostKeyChecking no
	UserKnownHostsFile=/dev/null

workspace.sh

#!/usr/bin/env bash
set -euo pipefail

# README
#
# This script creates a BitBar application that lets you manage a Droplet
# suitable for daily development use. When you're done working, it will power
# down, snapshot, and destroy the droplet to save you money.
#
# When you're ready to work again, it will create a new Droplet from the
# snapshot and assign a floating IP to it.
#
# Credit to @andrewhamon for the idea. I just made it a BitBar application.
# See https://github.com/andrewhamon/pcmd

################################################################################
# Configuration
# ——————————————————————————————————————————————————————————————————————————————
# You can duplicate this file and change the $NAME variable to have multiple
# workspaces. Make sure you make all $NAMEs unique. Beware DigitalOcean's rate
# limits when doing this.
################################################################################

# The name given in the Mac menu bar
NICKNAME="Workspace"

# The DigitalOcean Droplet size, image and region
SIZE=s-6vcpu-16gb
IMAGE=ubuntu-18-04-x64
REGION=sfo3

# The name given to the actual Droplet and the prefix given to every snapshot.
# If you have multiple copies of this script, you should change this to a unique
# name in each one.
NAME=workspace.$IMAGE

# The IP of a floating IP you MUST set up before using this script. It will give
# your Droplet a stable IP address to SSH into. It does cost a few dollars a
# month when it's not assigned to a Droplet.
FLOATING_IP=64.225.89.72

################################################################################
# Code (no need to edit)
################################################################################

export PATH="/usr/local/bin:$PATH"

if ! command -v jq &> /dev/null; then
    echo "Ensure jq is installed."
    exit
fi

if ! command -v doctl &> /dev/null; then
    echo "Ensure doctl is installed and authenticated."
    exit
fi

log(){
  echo $@ >&2
}

# Run commands with stdout and stderr redirected to /dev/null
shush(){
  $@ &>/dev/null
}

fetch_ssh_keys(){
  log "Fetching account SSH keys"

  # Join ids with a comma, and delete the trailing comma
  doctl compute ssh-key list --format ID --no-header | tr '\n' ',' | sed 's/,$//'
}

# Find the most recent snapshot that includes the VPS name as the prefix of the
# snapshot name
fetch_latest_snapshot(){
  local prefix=$1

  # log "Checking for existing snapshot"
  doctl compute snapshot list --format Name,ID --no-header | grep $prefix | sort | tail -1 | awk '{print $NF}'
}

fetch_running_droplet(){
  local prefix=$1

  log "Checking for existing droplet"
  doctl compute droplet list --format Name,ID --no-header | grep $prefix | tail -1 | awk '{print $NF}'
}

create_and_wait(){
  local image=$1

  local ssh_keys=$(fetch_ssh_keys)

  log "Creating instance $NAME"
  doctl compute droplet create $NAME \
    --image $image \
    --region $REGION \
    --size $SIZE \
    --ssh-keys $ssh_keys \
    --enable-monitoring \
    --enable-private-networking \
    --enable-ipv6 \
    --format ID,PublicIPv4 \
    --no-header \
    --wait
}

assign_floating_ip_and_wait(){
  local instance_id=$1

  log "Assigning floating IP $FLOATING_IP to $instance_id"
  doctl compute floating-ip-action assign $FLOATING_IP $instance_id
}

shutdown_and_wait(){
  local instance_id=$1

  log "Shutting down"
  shush doctl compute droplet-action shutdown $instance_id --wait
}

snapshot_and_wait(){
  local old_snapshot_id=$(fetch_latest_snapshot $NAME)

  local instance_id=$1
  local snapshot_name=$NAME.$(date -u +"%Y-%m-%dT%H:%M:%SZ")

  log "Taking snapshot"
  shush doctl compute droplet-action snapshot $instance_id --snapshot-name $snapshot_name --wait
}

delete(){
  local instance_id=$1

  log "Deleting instance"
  shush doctl compute droplet delete --force $instance_id
}

start(){
  local latest_snapshot_id=$(fetch_latest_snapshot $NAME)
  local create_result

  case $latest_snapshot_id in
  (*[![:space:]]*)
    log "Snapshot found: $latest_snapshot_id"
    create_and_wait $latest_snapshot_id
    ;;
  (*)
    log "Snapshot not found"
    create_and_wait $IMAGE
    ;;
  esac

  local instance_id=$(fetch_running_droplet $NAME)
  assign_floating_ip_and_wait $instance_id
}

stop(){
  local instance_id=$(fetch_running_droplet $NAME)
  shutdown_and_wait $instance_id
  snapshot_and_wait $instance_id
  delete $instance_id
}

fetch_status() {
  local prefix=$1
  local status=$(doctl compute droplet list --format Name,Status --no-header | grep $prefix | tail -1 | awk '{print $NF}')

  if [ -z "$status" ]; then
    echo "🔴"
  else
    echo "🟢 $status"
  fi
}

if [ $# -eq 0 ]; then
  status=$(fetch_status $NAME)
  amount=$(doctl invoice summary preview --format Amount --no-header)
  echo "$NICKNAME $status"
  echo "---"

  echo "Usage: \$$amount"

  if [ "$status" = "🔴" ]; then
    echo "Start $NICKNAME | bash='$0 start'"
  else
    echo "Stop $NICKNAME | bash='$0 stop'"
  fi
else
  case $1 in
  "start")
    start
    ;;
  "stop")
    stop
    ;;
  "cleanup")
    cleanup_old_snapshots
  esac
fi