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content/blog/autodeployterraform.md

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+---
+title: "Automatic Deployments with Terraform"
+date: 2020-05-08T22:45:18-04:00
+draft: false
+tags: []
+---
+
+I have recently written about [Packer](https://brandonrozek.com/blog/snapshotswithpacker/) to create system images or snapshots. This post will go over another [HashiCorp](https://www.hashicorp.com/) project named [Terraform](https://www.terraform.io/) that we can use to deploy that image to a VPS. Like before, I am going to go over how to setup this up in DigitalOcean. Check out [this list](https://www.terraform.io/docs/providers/index.html) for documentation on your favorite cloud provider.
+
+## Variables
+
+To protect against committing secrets like API keys, we're going to create a file that only stores variables. For it to be loaded automatically, it needs to be named `terraform.tfvars`. Here is an example configuration:
+
+```
+region = "nyc3"
+size = "512mb"
+domain = "example.com"
+subdomain = "temp"
+
+# Secrets
+do_token = "DO-TOKEN-HERE"
+key_name = "SSH-KEY-NAME-ON-DO"
+```
+
+Now to define the variables in HCL, we need to create a separate `variables.tf` file defining their types
+
+```
+variable "do_token" {
+  type = string
+}
+
+variable "domain" {
+  type = string
+}
+
+variable "key_name" {
+  type = string
+}
+
+variable "subdomain" {
+  type = string
+}
+
+variable "region" {
+  type = string
+}
+
+variable "size" {
+  type = string
+}
+
+```
+
+## Configuration
+
+Now let's create a file called `do.tf`.  We need to start off by stating which provider we are using
+
+```
+provider "digitalocean" {
+    token = var.do_token
+}
+```
+
+If you want to hook up your SSH key, then we need to query the Digital Ocean API for its ID.
+
+```
+data "digitalocean_ssh_key" laptop {
+    name = var.key_name
+}
+```
+
+We need to also query the API for the packer snapshot we created. Replace this with any standard image like `"ubuntu-20-04-x64"` if you don't want to use a snapshot.
+
+```
+data "digitalocean_droplet_snapshot" "packer_snapshot" {
+    name = "packer-example"
+    most_recent = true
+}
+```
+
+Now we can create the droplet
+
+```
+resource "digitalocean_droplet" "web" {
+    name = "tf-1"
+    image = data.digitalocean_droplet_snapshot.packer_snapshot.id
+    region = var.region
+    size = var.size
+    ssh_keys = [data.digitalocean_ssh_key.laptop.id]
+    backups = false
+}
+```
+
+Attach a domain to the droplet
+
+```
+resource "digitalocean_record" "www" {
+  domain = var.domain
+  type   = "A"
+  name   = var.subdomain
+  value  = digitalocean_droplet.web.ipv4_address
+}
+```
+
+Output useful pieces of information like the new system's IP address and the domain
+
+```
+output "ip" {
+    value = digitalocean_droplet.web.ipv4_address
+}
+
+output "domain" {
+    value = "${digitalocean_record.www.name}.${digitalocean_record.www.domain}"
+}
+```
+
+The whole configuration file for your convenience:
+
+```
+provider "digitalocean" {
+    token = var.do_token
+}
+
+data "digitalocean_ssh_key" laptop {
+    name = var.key_name
+}
+
+data "digitalocean_droplet_snapshot" "packer_snapshot" {
+    name = "packer-example"
+    most_recent = true
+}
+
+# Create a droplet
+resource "digitalocean_droplet" "web" {
+    name = "tf-1"
+    image = data.digitalocean_droplet_snapshot.packer_snapshot.id
+    region = var.region
+    size = var.size
+    ssh_keys = [data.digitalocean_ssh_key.laptop.id]
+    backups = false
+}
+
+# Attach a subdomain
+resource "digitalocean_record" "www" {
+  domain = var.domain
+  type   = "A"
+  name   = var.subdomain
+  value  = digitalocean_droplet.web.ipv4_address
+}
+
+output "ip" {
+    value = digitalocean_droplet.web.ipv4_address
+}
+
+output "domain" {
+    value = "${digitalocean_record.www.name}.${digitalocean_record.www.domain}"
+}
+```
+
+# Deploy
+
+Check if your configuration is valid
+
+```bash
+terraform plan
+```
+
+Deploy!
+
+```bash
+terraform apply
+```
+
+Take down when done
+
+```bash
+terraform destroy
+```
+