Files
terraform-aws-eks/modules/karpenter/main.tf
2023-05-17 10:04:11 -04:00

380 lines
11 KiB
HCL

data "aws_partition" "current" {}
data "aws_caller_identity" "current" {}
locals {
account_id = data.aws_caller_identity.current.account_id
partition = data.aws_partition.current.partition
dns_suffix = data.aws_partition.current.dns_suffix
}
################################################################################
# IAM Role for Service Account (IRSA)
# This is used by the Karpenter controller
################################################################################
locals {
create_irsa = var.create && var.create_irsa
irsa_name = coalesce(var.irsa_name, "KarpenterIRSA-${var.cluster_name}")
irsa_policy_name = coalesce(var.irsa_policy_name, local.irsa_name)
irsa_oidc_provider_url = replace(var.irsa_oidc_provider_arn, "/^(.*provider/)/", "")
}
data "aws_iam_policy_document" "irsa_assume_role" {
count = local.create_irsa ? 1 : 0
statement {
effect = "Allow"
actions = ["sts:AssumeRoleWithWebIdentity"]
principals {
type = "Federated"
identifiers = [var.irsa_oidc_provider_arn]
}
condition {
test = var.irsa_assume_role_condition_test
variable = "${local.irsa_oidc_provider_url}:sub"
values = [for sa in var.irsa_namespace_service_accounts : "system:serviceaccount:${sa}"]
}
# https://aws.amazon.com/premiumsupport/knowledge-center/eks-troubleshoot-oidc-and-irsa/?nc1=h_ls
condition {
test = var.irsa_assume_role_condition_test
variable = "${local.irsa_oidc_provider_url}:aud"
values = ["sts.amazonaws.com"]
}
}
}
resource "aws_iam_role" "irsa" {
count = local.create_irsa ? 1 : 0
name = var.irsa_use_name_prefix ? null : local.irsa_name
name_prefix = var.irsa_use_name_prefix ? "${local.irsa_name}-" : null
path = var.irsa_path
description = var.irsa_description
assume_role_policy = data.aws_iam_policy_document.irsa_assume_role[0].json
max_session_duration = var.irsa_max_session_duration
permissions_boundary = var.irsa_permissions_boundary_arn
force_detach_policies = true
tags = merge(var.tags, var.irsa_tags)
}
locals {
irsa_tag_values = coalescelist([var.cluster_name], var.irsa_tag_values)
}
data "aws_iam_policy_document" "irsa" {
count = local.create_irsa ? 1 : 0
statement {
actions = [
"ec2:CreateLaunchTemplate",
"ec2:CreateFleet",
"ec2:CreateTags",
"ec2:DescribeLaunchTemplates",
"ec2:DescribeImages",
"ec2:DescribeInstances",
"ec2:DescribeSecurityGroups",
"ec2:DescribeSubnets",
"ec2:DescribeInstanceTypes",
"ec2:DescribeInstanceTypeOfferings",
"ec2:DescribeAvailabilityZones",
"ec2:DescribeSpotPriceHistory",
"pricing:GetProducts",
]
resources = ["*"]
}
statement {
actions = [
"ec2:TerminateInstances",
"ec2:DeleteLaunchTemplate",
]
resources = ["*"]
condition {
test = "StringEquals"
variable = "ec2:ResourceTag/${var.irsa_tag_key}"
values = local.irsa_tag_values
}
}
statement {
actions = ["ec2:RunInstances"]
resources = [
"arn:${local.partition}:ec2:*:${local.account_id}:launch-template/*",
]
condition {
test = "StringEquals"
variable = "ec2:ResourceTag/${var.irsa_tag_key}"
values = local.irsa_tag_values
}
}
statement {
actions = ["ec2:RunInstances"]
resources = [
"arn:${local.partition}:ec2:*::image/*",
"arn:${local.partition}:ec2:*:${local.account_id}:instance/*",
"arn:${local.partition}:ec2:*:${local.account_id}:spot-instances-request/*",
"arn:${local.partition}:ec2:*:${local.account_id}:security-group/*",
"arn:${local.partition}:ec2:*:${local.account_id}:volume/*",
"arn:${local.partition}:ec2:*:${local.account_id}:network-interface/*",
"arn:${local.partition}:ec2:*:${coalesce(var.irsa_subnet_account_id, local.account_id)}:subnet/*",
]
}
statement {
actions = ["ssm:GetParameter"]
resources = var.irsa_ssm_parameter_arns
}
statement {
actions = ["eks:DescribeCluster"]
resources = ["arn:${local.partition}:eks:*:${local.account_id}:cluster/${var.cluster_name}"]
}
statement {
actions = ["iam:PassRole"]
resources = [var.create_iam_role ? aws_iam_role.this[0].arn : var.iam_role_arn]
}
dynamic "statement" {
for_each = local.enable_spot_termination ? [1] : []
content {
actions = [
"sqs:DeleteMessage",
"sqs:GetQueueUrl",
"sqs:GetQueueAttributes",
"sqs:ReceiveMessage",
]
resources = [aws_sqs_queue.this[0].arn]
}
}
}
resource "aws_iam_policy" "irsa" {
count = local.create_irsa ? 1 : 0
name_prefix = "${local.irsa_policy_name}-"
path = var.irsa_path
description = var.irsa_description
policy = data.aws_iam_policy_document.irsa[0].json
tags = var.tags
}
resource "aws_iam_role_policy_attachment" "irsa" {
count = local.create_irsa ? 1 : 0
role = aws_iam_role.irsa[0].name
policy_arn = aws_iam_policy.irsa[0].arn
}
resource "aws_iam_role_policy_attachment" "irsa_additional" {
for_each = { for k, v in var.policies : k => v if local.create_irsa }
role = aws_iam_role.irsa[0].name
policy_arn = each.value
}
################################################################################
# Node Termination Queue
################################################################################
locals {
enable_spot_termination = var.create && var.enable_spot_termination
queue_name = coalesce(var.queue_name, "Karpenter-${var.cluster_name}")
}
resource "aws_sqs_queue" "this" {
count = local.enable_spot_termination ? 1 : 0
name = local.queue_name
message_retention_seconds = 300
sqs_managed_sse_enabled = var.queue_managed_sse_enabled ? var.queue_managed_sse_enabled : null
kms_master_key_id = var.queue_kms_master_key_id
kms_data_key_reuse_period_seconds = var.queue_kms_data_key_reuse_period_seconds
tags = var.tags
}
data "aws_iam_policy_document" "queue" {
count = local.enable_spot_termination ? 1 : 0
statement {
sid = "SqsWrite"
actions = ["sqs:SendMessage"]
resources = [aws_sqs_queue.this[0].arn]
principals {
type = "Service"
identifiers = [
"events.${local.dns_suffix}",
"sqs.${local.dns_suffix}",
]
}
}
}
resource "aws_sqs_queue_policy" "this" {
count = local.enable_spot_termination ? 1 : 0
queue_url = aws_sqs_queue.this[0].url
policy = data.aws_iam_policy_document.queue[0].json
}
################################################################################
# Node Termination Event Rules
################################################################################
locals {
events = {
health_event = {
name = "HealthEvent"
description = "Karpenter interrupt - AWS health event"
event_pattern = {
source = ["aws.health"]
detail-type = ["AWS Health Event"]
}
}
spot_interupt = {
name = "SpotInterrupt"
description = "Karpenter interrupt - EC2 spot instance interruption warning"
event_pattern = {
source = ["aws.ec2"]
detail-type = ["EC2 Spot Instance Interruption Warning"]
}
}
instance_rebalance = {
name = "InstanceRebalance"
description = "Karpenter interrupt - EC2 instance rebalance recommendation"
event_pattern = {
source = ["aws.ec2"]
detail-type = ["EC2 Instance Rebalance Recommendation"]
}
}
instance_state_change = {
name = "InstanceStateChange"
description = "Karpenter interrupt - EC2 instance state-change notification"
event_pattern = {
source = ["aws.ec2"]
detail-type = ["EC2 Instance State-change Notification"]
}
}
}
}
resource "aws_cloudwatch_event_rule" "this" {
for_each = { for k, v in local.events : k => v if local.enable_spot_termination }
name_prefix = "${var.rule_name_prefix}${each.value.name}-"
description = each.value.description
event_pattern = jsonencode(each.value.event_pattern)
tags = merge(
{ "ClusterName" : var.cluster_name },
var.tags,
)
}
resource "aws_cloudwatch_event_target" "this" {
for_each = { for k, v in local.events : k => v if local.enable_spot_termination }
rule = aws_cloudwatch_event_rule.this[each.key].name
target_id = "KarpenterInterruptionQueueTarget"
arn = aws_sqs_queue.this[0].arn
}
################################################################################
# Node IAM Role
# This is used by the nodes launched by Karpenter
################################################################################
locals {
create_iam_role = var.create && var.create_iam_role
iam_role_name = coalesce(var.iam_role_name, "Karpenter-${var.cluster_name}")
iam_role_policy_prefix = "arn:${local.partition}:iam::aws:policy"
cni_policy = var.cluster_ip_family == "ipv6" ? "${local.iam_role_policy_prefix}/AmazonEKS_CNI_IPv6_Policy" : "${local.iam_role_policy_prefix}/AmazonEKS_CNI_Policy"
}
data "aws_iam_policy_document" "assume_role" {
count = local.create_iam_role ? 1 : 0
statement {
sid = "EKSNodeAssumeRole"
actions = ["sts:AssumeRole"]
principals {
type = "Service"
identifiers = ["ec2.${local.dns_suffix}"]
}
}
}
resource "aws_iam_role" "this" {
count = local.create_iam_role ? 1 : 0
name = var.iam_role_use_name_prefix ? null : local.iam_role_name
name_prefix = var.iam_role_use_name_prefix ? "${local.iam_role_name}-" : null
path = var.iam_role_path
description = var.iam_role_description
assume_role_policy = data.aws_iam_policy_document.assume_role[0].json
max_session_duration = var.iam_role_max_session_duration
permissions_boundary = var.iam_role_permissions_boundary
force_detach_policies = true
tags = merge(var.tags, var.iam_role_tags)
}
# Policies attached ref https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/eks_node_group
resource "aws_iam_role_policy_attachment" "this" {
for_each = { for k, v in toset(compact([
"${local.iam_role_policy_prefix}/AmazonEKSWorkerNodePolicy",
"${local.iam_role_policy_prefix}/AmazonEC2ContainerRegistryReadOnly",
var.iam_role_attach_cni_policy ? local.cni_policy : "",
])) : k => v if local.create_iam_role }
policy_arn = each.value
role = aws_iam_role.this[0].name
}
resource "aws_iam_role_policy_attachment" "additional" {
for_each = { for k, v in var.iam_role_additional_policies : k => v if local.create_iam_role }
policy_arn = each.value
role = aws_iam_role.this[0].name
}
################################################################################
# Node IAM Instance Profile
# This is used by the nodes launched by Karpenter
################################################################################
locals {
external_role_name = try(replace(var.iam_role_arn, "/^(.*role/)/", ""), null)
}
resource "aws_iam_instance_profile" "this" {
count = var.create && var.create_instance_profile ? 1 : 0
name = var.iam_role_use_name_prefix ? null : local.iam_role_name
name_prefix = var.iam_role_use_name_prefix ? "${local.iam_role_name}-" : null
path = var.iam_role_path
role = var.create_iam_role ? aws_iam_role.this[0].name : local.external_role_name
tags = merge(var.tags, var.iam_role_tags)
}