Using Terraform with Digital Ocean

tf.do.md

Using Terraform with Digital Ocean

Note: Still in draft form. Need to flesh out a bit.

From https://www.digitalocean.com/community/tutorials/how-to-use-terraform-with-digitalocean

Setup

On the Digital Ocean site:

1. Create and save a Digital Ocean token.
2. Create an SSH key called '~/.ssh/id_digital_ocean' without a passphrase and upload to Digital Ocean with the name "digital_ocean".

export DO_PAT="${DO_TOKEN}"
export DO_SSH_KEY_NAME="digital_ocean"

Create a background container

docker container run \
  -d \
  --name tform \
  -v ~/.ssh/id_digital_ocean:/tmp/id_digital_ocean:ro \
  ubuntu sleep inf ; sleep 1

Exec into the container

This verifies that the container works.

docker container exec -it tform  /bin/bash

Install terraform in the container

These are items that will eventually make it into a Dockerfile.

docker container exec -i tform /bin/bash << 'eof'  
  export DEBIAN_FRONTEND=noninteractive
  apt-get update
  apt-get install -y curl unzip zip tree vim jq file elinks less

  # fetch hcl2json binary
  curl -L --output-dir /usr/local/bin -O \
    https://github.com/tmccombs/hcl2json/releases/download/v0.6.0/hcl2json_linux_amd64
  chmod +x /usr/local/bin/hcl2json_linux_amd64

  # fetch and install the latest terraform binary
  elinks --dump 'https://releases.hashicorp.com/terraform' |
    grep -v alpha |
    grep -m 1 -o 'https://.*terraform/.*$' |
    xargs elinks --dump |
    grep -m 1 -o 'https://.*_linux_amd64.zip' |
    xargs curl -o /tmp/terraform.zip
  unzip /tmp/terraform.zip -d /usr/local/bin
  rm /tmp/terraform.zip

  mkdir /root/loadbalance
eof

Configure terraform in the container for Digital Ocean

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -e DO_SSH_KEY_NAME="${DO_SSH_KEY_NAME}" \
    -e TF_LOG=1 \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  cut -c5- <<eof2 > provider.tf
    terraform {
      required_providers {
        digitalocean = {
          source = "digitalocean/digitalocean"
          version = "~> 2.0"
        }
      }
    }

    variable "do_token" {}
    variable "pvt_key" {}

    provider "digitalocean" {
      token = var.do_token
    }

    data "digitalocean_ssh_key" "${DO_SSH_KEY_NAME}" {
      name = "${DO_SSH_KEY_NAME}"
    }
eof2

  terraform init
eof

Configure Digital Ocean infrastructure using terraform

This sets up a single droplet.

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -e DO_SSH_KEY_NAME="${DO_SSH_KEY_NAME}" \
    -e TF_LOG=1 \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  cut -c5- <<eof2 > www-1.tf
    resource "digitalocean_droplet" "www-1" {
      image = "ubuntu-22-04-x64"
      name = "www-1"
      region = "sfo3"
      size = "s-1vcpu-512mb-10gb"
      ssh_keys = [
        data.digitalocean_ssh_key.${DO_SSH_KEY_NAME}.id
      ]
    }
eof2
eof

Plan Digital Ocean infrastructure using terraform

This is similar to a dry-run. Terraform informs you about what it will do if you were to deploy ( i.e. apply ).

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  terraform plan \
    -var "do_token=${DO_PAT}" \
    -var "pvt_key=/tmp/id_digital_ocean"

eof

Deploy (apply) Digital Ocean infrastructure using terraform

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  terraform apply -auto-approve \
    -var "do_token=${DO_PAT}" \
    -var "pvt_key=/tmp/id_digital_ocean"

eof

Query (show) Digital Ocean infrastructure state using terraform

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  terraform show terraform.tfstate

eof

Query (refresh) Digital Ocean infrastructure state using terraform

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  terraform refresh \
    -var "do_token=${DO_PAT}" \
    -var "pvt_key=/tmp/id_digital_ocean"

eof

Destroy Digital Ocean infrastructure using terraform

This does both the dry-run ( plan ) and deploy ( apply ).

docker container exec \
    -i \
    -e DO_PAT="${DO_TOKEN}" \
    -w /root/loadbalance \
    tform /bin/bash << 'eof'

  terraform plan -destroy -out=terraform.tfplan \
    -var "do_token=${DO_PAT}" \
    -var "pvt_key=/tmp/id_digital_ocean"

  terraform apply terraform.tfplan
eof

Destroy container

docker container stop tform ; docker container rm tform ;