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Migrate DigitalOcean module from Terraform v0.11 to v0.12

Browse Source 
* Replace v0.11 bracket type hints with Terraform v0.12 list expressions
* Use expression syntax instead of interpolated strings, where suggested
* Update DigitalOcean tutorial documentation
* Define Terraform and plugin version requirements in versions.tf
  * Require digitalocean ~> v1.3 to support Terraform v0.12
  * Require ct ~> v0.3.2 to support Terraform v0.12
This commit is contained in:
Dalton Hubble 2019-05-27 15:37:36 -07:00
parent 0ccb2217b5
commit 1366ae404b
11 changed files with 211 additions and 241 deletions
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6
CHANGES.md
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@ -2,6 +2,12 @@
Notable changes between versions.
#### DigitalOcean
* Migrate from Terraform v0.11 to v0.12.x (**action required!**)
* Require `terraform-provider-digitalocean` v1.3+ to support Terraform v0.12
* Require `terraform-provider-ct` ~> v0.3.2+ to support Terraform v0.12
## Latest
## v1.14.3

23
digital-ocean/container-linux/kubernetes/bootkube.tf
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@ -1,21 +1,22 @@
# Self-hosted Kubernetes assets (kubeconfig, manifests)
module "bootkube" {
source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=082921d67905417755609eebda7d39a7e26f7fdb"
source = "git::https://github.com/poseidon/terraform-render-bootkube.git?ref=0103bc06bb3f597455a765bf5d916f9b241cbea0"
cluster_name = "${var.cluster_name}"
api_servers = ["${format("%s.%s", var.cluster_name, var.dns_zone)}"]
etcd_servers = "${digitalocean_record.etcds.*.fqdn}"
asset_dir = "${var.asset_dir}"
cluster_name = var.cluster_name
api_servers = [format("%s.%s", var.cluster_name, var.dns_zone)]
etcd_servers = digitalocean_record.etcds.*.fqdn
asset_dir = var.asset_dir
networking = "${var.networking}"
networking = var.networking
# only effective with Calico networking
network_encapsulation = "vxlan"
network_mtu = "1450"
pod_cidr = "${var.pod_cidr}"
service_cidr = "${var.service_cidr}"
cluster_domain_suffix = "${var.cluster_domain_suffix}"
enable_reporting = "${var.enable_reporting}"
enable_aggregation = "${var.enable_aggregation}"
pod_cidr = var.pod_cidr
service_cidr = var.service_cidr
cluster_domain_suffix = var.cluster_domain_suffix
enable_reporting = var.enable_reporting
enable_aggregation = var.enable_aggregation
}

58
digital-ocean/container-linux/kubernetes/controllers.tf
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@ -1,25 +1,25 @@
# Controller Instance DNS records
resource "digitalocean_record" "controllers" {
count = "${var.controller_count}"
count = var.controller_count
# DNS zone where record should be created
domain = "${var.dns_zone}"
domain = var.dns_zone
# DNS record (will be prepended to domain)
name = "${var.cluster_name}"
name = var.cluster_name
type = "A"
ttl = 300
# IPv4 addresses of controllers
value = "${element(digitalocean_droplet.controllers.*.ipv4_address, count.index)}"
value = element(digitalocean_droplet.controllers.*.ipv4_address, count.index)
}
# Discrete DNS records for each controller's private IPv4 for etcd usage
resource "digitalocean_record" "etcds" {
count = "${var.controller_count}"
count = var.controller_count
# DNS zone where record should be created
domain = "${var.dns_zone}"
domain = var.dns_zone
# DNS record (will be prepended to domain)
name = "${var.cluster_name}-etcd${count.index}"
@ -27,34 +27,32 @@ resource "digitalocean_record" "etcds" {
ttl = 300
# private IPv4 address for etcd
value = "${element(digitalocean_droplet.controllers.*.ipv4_address_private, count.index)}"
value = element(digitalocean_droplet.controllers.*.ipv4_address_private, count.index)
}
# Controller droplet instances
resource "digitalocean_droplet" "controllers" {
count = "${var.controller_count}"
count = var.controller_count
name = "${var.cluster_name}-controller-${count.index}"
region = "${var.region}"
region = var.region
image = "${var.image}"
size = "${var.controller_type}"
image = var.image
size = var.controller_type
# network
ipv6 = true
private_networking = true
user_data = "${element(data.ct_config.controller-ignitions.*.rendered, count.index)}"
ssh_keys = ["${var.ssh_fingerprints}"]
user_data = element(data.ct_config.controller-ignitions.*.rendered, count.index)
ssh_keys = var.ssh_fingerprints
tags = [
"${digitalocean_tag.controllers.id}",
digitalocean_tag.controllers.id,
]
lifecycle {
ignore_changes = [
"user_data",
]
ignore_changes = [user_data]
}
}
@ -65,37 +63,37 @@ resource "digitalocean_tag" "controllers" {
# Controller Ignition configs
data "ct_config" "controller-ignitions" {
count = "${var.controller_count}"
content = "${element(data.template_file.controller-configs.*.rendered, count.index)}"
count = var.controller_count
content = element(data.template_file.controller-configs.*.rendered, count.index)
pretty_print = false
snippets = ["${var.controller_clc_snippets}"]
snippets = var.controller_clc_snippets
}
# Controller Container Linux configs
data "template_file" "controller-configs" {
count = "${var.controller_count}"
count = var.controller_count
template = "${file("${path.module}/cl/controller.yaml.tmpl")}"
template = file("${path.module}/cl/controller.yaml.tmpl")
vars = {
# Cannot use cyclic dependencies on controllers or their DNS records
etcd_name = "etcd${count.index}"
etcd_domain = "${var.cluster_name}-etcd${count.index}.${var.dns_zone}"
# etcd0=https://cluster-etcd0.example.com,etcd1=https://cluster-etcd1.example.com,...
etcd_initial_cluster = "${join(",", data.template_file.etcds.*.rendered)}"
cluster_dns_service_ip = "${cidrhost(var.service_cidr, 10)}"
cluster_domain_suffix = "${var.cluster_domain_suffix}"
etcd_initial_cluster = join(",", data.template_file.etcds.*.rendered)
cluster_dns_service_ip = cidrhost(var.service_cidr, 10)
cluster_domain_suffix = var.cluster_domain_suffix
}
}
data "template_file" "etcds" {
count = "${var.controller_count}"
count = var.controller_count
template = "etcd$${index}=https://$${cluster_name}-etcd$${index}.$${dns_zone}:2380"
vars = {
index = "${count.index}"
cluster_name = "${var.cluster_name}"
dns_zone = "${var.dns_zone}"
index = count.index
cluster_name = var.cluster_name
dns_zone = var.dns_zone
}
}

150
digital-ocean/container-linux/kubernetes/network.tf
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@ -1,50 +1,51 @@
resource "digitalocean_firewall" "rules" {
name = "${var.cluster_name}"
name = var.cluster_name
tags = ["${var.cluster_name}-controller", "${var.cluster_name}-worker"]
# allow ssh, internal flannel, internal node-exporter, internal kubelet
inbound_rule = [
{
protocol = "tcp"
port_range = "22"
source_addresses = ["0.0.0.0/0", "::/0"]
},
{
protocol = "udp"
port_range = "4789"
source_tags = ["${digitalocean_tag.controllers.name}", "${digitalocean_tag.workers.name}"]
},
{
protocol = "tcp"
port_range = "9100"
source_tags = ["${digitalocean_tag.workers.name}"]
},
{
protocol = "tcp"
port_range = "10250"
source_tags = ["${digitalocean_tag.controllers.name}", "${digitalocean_tag.workers.name}"]
},
]
inbound_rule {
protocol = "tcp"
port_range = "22"
source_addresses = ["0.0.0.0/0", "::/0"]
}
inbound_rule {
protocol = "udp"
port_range = "4789"
source_tags = [digitalocean_tag.controllers.name, digitalocean_tag.workers.name]
}
inbound_rule {
protocol = "tcp"
port_range = "9100"
source_tags = [digitalocean_tag.workers.name]
}
inbound_rule {
protocol = "tcp"
port_range = "10250"
source_tags = [digitalocean_tag.controllers.name, digitalocean_tag.workers.name]
}
# allow all outbound traffic
outbound_rule = [
{
protocol = "tcp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
},
{
protocol = "udp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
},
{
protocol = "icmp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
},
]
outbound_rule {
protocol = "tcp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
}
outbound_rule {
protocol = "udp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
}
outbound_rule {
protocol = "icmp"
port_range = "1-65535"
destination_addresses = ["0.0.0.0/0", "::/0"]
}
}
resource "digitalocean_firewall" "controllers" {
@ -53,23 +54,23 @@ resource "digitalocean_firewall" "controllers" {
tags = ["${var.cluster_name}-controller"]
# etcd, kube-apiserver, kubelet
inbound_rule = [
{
protocol = "tcp"
port_range = "2379-2380"
source_tags = ["${digitalocean_tag.controllers.name}"]
},
{
protocol = "tcp"
port_range = "2381"
source_tags = ["${digitalocean_tag.workers.name}"]
},
{
protocol = "tcp"
port_range = "6443"
source_addresses = ["0.0.0.0/0", "::/0"]
},
]
inbound_rule {
protocol = "tcp"
port_range = "2379-2380"
source_tags = [digitalocean_tag.controllers.name]
}
inbound_rule {
protocol = "tcp"
port_range = "2381"
source_tags = [digitalocean_tag.workers.name]
}
inbound_rule {
protocol = "tcp"
port_range = "6443"
source_addresses = ["0.0.0.0/0", "::/0"]
}
}
resource "digitalocean_firewall" "workers" {
@ -78,21 +79,22 @@ resource "digitalocean_firewall" "workers" {
tags = ["${var.cluster_name}-worker"]
# allow HTTP/HTTPS ingress
inbound_rule = [
{
protocol = "tcp"
port_range = "80"
source_addresses = ["0.0.0.0/0", "::/0"]
},
{
protocol = "tcp"
port_range = "443"
source_addresses = ["0.0.0.0/0", "::/0"]
},
{
protocol = "tcp"
port_range = "10254"
source_addresses = ["0.0.0.0/0"]
},
]
inbound_rule {
protocol = "tcp"
port_range = "80"
source_addresses = ["0.0.0.0/0", "::/0"]
}
inbound_rule {
protocol = "tcp"
port_range = "443"
source_addresses = ["0.0.0.0/0", "::/0"]
}
inbound_rule {
protocol = "tcp"
port_range = "10254"
source_addresses = ["0.0.0.0/0"]
}
}

19
digital-ocean/container-linux/kubernetes/outputs.tf
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@ -1,40 +1,41 @@
output "kubeconfig-admin" {
value = "${module.bootkube.kubeconfig-admin}"
value = module.bootkube.kubeconfig-admin
}
output "controllers_dns" {
value = "${digitalocean_record.controllers.0.fqdn}"
value = digitalocean_record.controllers[0].fqdn
}
output "workers_dns" {
# Multiple A and AAAA records with the same FQDN
value = "${digitalocean_record.workers-record-a.0.fqdn}"
value = digitalocean_record.workers-record-a[0].fqdn
}
output "controllers_ipv4" {
value = ["${digitalocean_droplet.controllers.*.ipv4_address}"]
value = [digitalocean_droplet.controllers.*.ipv4_address]
}
output "controllers_ipv6" {
value = ["${digitalocean_droplet.controllers.*.ipv6_address}"]
value = [digitalocean_droplet.controllers.*.ipv6_address]
}
output "workers_ipv4" {
value = ["${digitalocean_droplet.workers.*.ipv4_address}"]
value = [digitalocean_droplet.workers.*.ipv4_address]
}
output "workers_ipv6" {
value = ["${digitalocean_droplet.workers.*.ipv6_address}"]
value = [digitalocean_droplet.workers.*.ipv6_address]
}
# Outputs for custom firewalls
output "controller_tag" {
description = "Tag applied to controller droplets"
value = "${digitalocean_tag.controllers.name}"
value = digitalocean_tag.controllers.name
}
output "worker_tag" {
description = "Tag applied to worker droplets"
value = "${digitalocean_tag.workers.name}"
value = digitalocean_tag.workers.name
}

25
digital-ocean/container-linux/kubernetes/require.tf
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@ -1,25 +0,0 @@
# Terraform version and plugin versions
terraform {
required_version = ">= 0.11.0"
}
provider "digitalocean" {
version = "~> 1.0"
}
provider "local" {
version = "~> 1.0"
}
provider "null" {
version = "~> 1.0"
}
provider "template" {
version = "~> 1.0"
}
provider "tls" {
version = "~> 1.0"
}

39
digital-ocean/container-linux/kubernetes/ssh.tf
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@ -1,55 +1,55 @@
# Secure copy etcd TLS assets and kubeconfig to controllers. Activates kubelet.service
resource "null_resource" "copy-controller-secrets" {
count = "${var.controller_count}"
count = var.controller_count
depends_on = [
"digitalocean_firewall.rules",
digitalocean_firewall.rules
]
connection {
type = "ssh"
host = "${element(concat(digitalocean_droplet.controllers.*.ipv4_address), count.index)}"
host = element(digitalocean_droplet.controllers.*.ipv4_address, count.index)
user = "core"
timeout = "15m"
}
provisioner "file" {
content = "${module.bootkube.kubeconfig-kubelet}"
content = module.bootkube.kubeconfig-kubelet
destination = "$HOME/kubeconfig"
}
provisioner "file" {
content = "${module.bootkube.etcd_ca_cert}"
content = module.bootkube.etcd_ca_cert
destination = "$HOME/etcd-client-ca.crt"
}
provisioner "file" {
content = "${module.bootkube.etcd_client_cert}"
content = module.bootkube.etcd_client_cert
destination = "$HOME/etcd-client.crt"
}
provisioner "file" {
content = "${module.bootkube.etcd_client_key}"
content = module.bootkube.etcd_client_key
destination = "$HOME/etcd-client.key"
}
provisioner "file" {
content = "${module.bootkube.etcd_server_cert}"
content = module.bootkube.etcd_server_cert
destination = "$HOME/etcd-server.crt"
}
provisioner "file" {
content = "${module.bootkube.etcd_server_key}"
content = module.bootkube.etcd_server_key
destination = "$HOME/etcd-server.key"
}
provisioner "file" {
content = "${module.bootkube.etcd_peer_cert}"
content = module.bootkube.etcd_peer_cert
destination = "$HOME/etcd-peer.crt"
}
provisioner "file" {
content = "${module.bootkube.etcd_peer_key}"
content = module.bootkube.etcd_peer_key
destination = "$HOME/etcd-peer.key"
}
@ -72,17 +72,17 @@ resource "null_resource" "copy-controller-secrets" {
# Secure copy kubeconfig to all workers. Activates kubelet.service.
resource "null_resource" "copy-worker-secrets" {
count = "${var.worker_count}"
count = var.worker_count
connection {
type = "ssh"
host = "${element(concat(digitalocean_droplet.workers.*.ipv4_address), count.index)}"
host = element(digitalocean_droplet.workers.*.ipv4_address, count.index)
user = "core"
timeout = "15m"
}
provisioner "file" {
content = "${module.bootkube.kubeconfig-kubelet}"
content = module.bootkube.kubeconfig-kubelet
destination = "$HOME/kubeconfig"
}
@ -97,20 +97,20 @@ resource "null_resource" "copy-worker-secrets" {
# one-time self-hosted cluster bootstrapping.
resource "null_resource" "bootkube-start" {
depends_on = [
"module.bootkube",
"null_resource.copy-controller-secrets",
"null_resource.copy-worker-secrets",
module.bootkube,
null_resource.copy-controller-secrets,
null_resource.copy-worker-secrets,
]
connection {
type = "ssh"
host = "${digitalocean_droplet.controllers.0.ipv4_address}"
host = digitalocean_droplet.controllers[0].ipv4_address
user = "core"
timeout = "15m"
}
provisioner "file" {
source = "${var.asset_dir}"
source = var.asset_dir
destination = "$HOME/assets"
}
@ -121,3 +121,4 @@ resource "null_resource" "bootkube-start" {
]
}
}

44
digital-ocean/container-linux/kubernetes/variables.tf
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@ -1,60 +1,60 @@
variable "cluster_name" {
type = "string"
type = string
description = "Unique cluster name (prepended to dns_zone)"
}
# Digital Ocean
variable "region" {
type = "string"
type = string
description = "Digital Ocean region (e.g. nyc1, sfo2, fra1, tor1)"
}
variable "dns_zone" {
type = "string"
type = string
description = "Digital Ocean domain (i.e. DNS zone) (e.g. do.example.com)"
}
# instances
variable "controller_count" {
type = "string"
type = string
default = "1"
description = "Number of controllers (i.e. masters)"
}
variable "worker_count" {
type = "string"
type = string
default = "1"
description = "Number of workers"
}
variable "controller_type" {
type = "string"
type = string
default = "s-2vcpu-2gb"
description = "Droplet type for controllers (e.g. s-2vcpu-2gb, s-2vcpu-4gb, s-4vcpu-8gb)."
}
variable "worker_type" {
type = "string"
type = string
default = "s-1vcpu-1gb"
description = "Droplet type for workers (e.g. s-1vcpu-1gb, s-1vcpu-2gb, s-2vcpu-2gb)"
}
variable "image" {
type = "string"
type = string
default = "coreos-stable"
description = "Container Linux image for instances (e.g. coreos-stable)"
}
variable "controller_clc_snippets" {
type = "list"
type = list(string)
description = "Controller Container Linux Config snippets"
default = []
}
variable "worker_clc_snippets" {
type = "list"
type = list(string)
description = "Worker Container Linux Config snippets"
default = []
}
@ -62,24 +62,24 @@ variable "worker_clc_snippets" {
# configuration
variable "ssh_fingerprints" {
type = "list"
type = list(string)
description = "SSH public key fingerprints. (e.g. see `ssh-add -l -E md5`)"
}
variable "asset_dir" {
description = "Path to a directory where generated assets should be placed (contains secrets)"
type = "string"
type = string
}
variable "networking" {
description = "Choice of networking provider (flannel or calico)"
type = "string"
type = string
default = "flannel"
}
variable "pod_cidr" {
description = "CIDR IPv4 range to assign Kubernetes pods"
type = "string"
type = string
default = "10.2.0.0/16"
}
@ -89,24 +89,26 @@ CIDR IPv4 range to assign Kubernetes services.
The 1st IP will be reserved for kube_apiserver, the 10th IP will be reserved for coredns.
EOD
type = "string"
type = string
default = "10.3.0.0/16"
}
variable "cluster_domain_suffix" {
description = "Queries for domains with the suffix will be answered by coredns. Default is cluster.local (e.g. foo.default.svc.cluster.local) "
type = "string"
default = "cluster.local"
type = string
default = "cluster.local"
}
variable "enable_reporting" {
type = "string"
type = string
description = "Enable usage or analytics reporting to upstreams (Calico)"
default = "false"
default = "false"
}
variable "enable_aggregation" {
description = "Enable the Kubernetes Aggregation Layer (defaults to false)"
type = "string"
default = "false"
type = string
default = "false"
}

12
digital-ocean/container-linux/kubernetes/versions.tf Normal file
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@ -0,0 +1,12 @@
# Terraform version and plugin versions
terraform {
required_version = "~> 0.12.0"
required_providers {
digitalocean = "~> 1.3"
ct = "~> 0.3.2"
template = "~> 2.1"
null = "~> 2.1"
}
}

37
digital-ocean/container-linux/kubernetes/workers.tf
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@ -1,47 +1,47 @@
# Worker DNS records
resource "digitalocean_record" "workers-record-a" {
count = "${var.worker_count}"
count = var.worker_count
# DNS zone where record should be created
domain = "${var.dns_zone}"
domain = var.dns_zone
name = "${var.cluster_name}-workers"
type = "A"
ttl = 300
value = "${element(digitalocean_droplet.workers.*.ipv4_address, count.index)}"
value = element(digitalocean_droplet.workers.*.ipv4_address, count.index)
}
resource "digitalocean_record" "workers-record-aaaa" {
count = "${var.worker_count}"
count = var.worker_count
# DNS zone where record should be created
domain = "${var.dns_zone}"
domain = var.dns_zone
name = "${var.cluster_name}-workers"
type = "AAAA"
ttl = 300
value = "${element(digitalocean_droplet.workers.*.ipv6_address, count.index)}"
value = element(digitalocean_droplet.workers.*.ipv6_address, count.index)
}
# Worker droplet instances
resource "digitalocean_droplet" "workers" {
count = "${var.worker_count}"
count = var.worker_count
name = "${var.cluster_name}-worker-${count.index}"
region = "${var.region}"
region = var.region
image = "${var.image}"
size = "${var.worker_type}"
image = var.image
size = var.worker_type
# network
ipv6 = true
private_networking = true
user_data = "${data.ct_config.worker-ignition.rendered}"
ssh_keys = ["${var.ssh_fingerprints}"]
user_data = data.ct_config.worker-ignition.rendered
ssh_keys = var.ssh_fingerprints
tags = [
"${digitalocean_tag.workers.id}",
digitalocean_tag.workers.id,
]
lifecycle {
@ -56,17 +56,18 @@ resource "digitalocean_tag" "workers" {
# Worker Ignition config
data "ct_config" "worker-ignition" {
content = "${data.template_file.worker-config.rendered}"
content = data.template_file.worker-config.rendered
pretty_print = false
snippets = ["${var.worker_clc_snippets}"]
snippets = var.worker_clc_snippets
}
# Worker Container Linux config
data "template_file" "worker-config" {
template = "${file("${path.module}/cl/worker.yaml.tmpl")}"
template = file("${path.module}/cl/worker.yaml.tmpl")
vars = {
cluster_dns_service_ip = "${cidrhost(var.service_cidr, 10)}"
cluster_domain_suffix = "${var.cluster_domain_suffix}"
cluster_dns_service_ip = cidrhost(var.service_cidr, 10)
cluster_domain_suffix = var.cluster_domain_suffix
}
}

39
docs/cl/digital-ocean.md
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@ -10,15 +10,15 @@ Controllers are provisioned to run an `etcd-member` peer and a `kubelet` service
* Digital Ocean Account and Token
* Digital Ocean Domain (registered Domain Name or delegated subdomain)
* Terraform v0.11.x and [terraform-provider-ct](https://github.com/poseidon/terraform-provider-ct) installed locally
* Terraform v0.12.x and [terraform-provider-ct](https://github.com/poseidon/terraform-provider-ct) installed locally
## Terraform Setup
Install [Terraform](https://www.terraform.io/downloads.html) v0.11.x on your system.
Install [Terraform](https://www.terraform.io/downloads.html) v0.12.x on your system.
```sh
$ terraform version
Terraform v0.11.14
Terraform v0.12.0
```
Add the [terraform-provider-ct](https://github.com/poseidon/terraform-provider-ct) plugin binary for your system to `~/.terraform.d/plugins/`, noting the final name.
@ -50,34 +50,13 @@ Configure the DigitalOcean provider to use your token in a `providers.tf` file.
```tf
provider "digitalocean" {
version = "~> 1.3.0"
version = "1.3.0"
token = "${chomp(file("~/.config/digital-ocean/token"))}"
alias = "default"
}
provider "ct" {
version = "0.3.2"
}
provider "local" {
version = "~> 1.0"
alias = "default"
}
provider "null" {
version = "~> 1.0"
alias = "default"
}
provider "template" {
version = "~> 1.0"
alias = "default"
}
provider "tls" {
version = "~> 1.0"
alias = "default"
}
```
## Cluster
@ -86,15 +65,7 @@ Define a Kubernetes cluster using the module `digital-ocean/container-linux/kube
```tf
module "digital-ocean-nemo" {
source = "git::https://github.com/poseidon/typhoon//digital-ocean/container-linux/kubernetes?ref=v1.14.3"
providers = {
digitalocean = "digitalocean.default"
local = "local.default"
null = "null.default"
template = "template.default"
tls = "tls.default"
}
source = "git::https://github.com/poseidon/typhoon//digital-ocean/container-linux/kubernetes?ref=v1.14.4"
# Digital Ocean
cluster_name = "nemo"