Why is terraform saying my required variable is not defined? - amazon-web-services

Question

TF project:
main.tf
inputs.tf
The contents are:
main.tf
locals {
common_tags = {
SECRET_MGR_HOST = "${var.SECRET_MGR_HOST}",
SECRET_MGR_SAFE = "${var.SECRET_MGR_SAFE}",
SECRET_MGR_SECRET_KEY_NAME = "${var.SECRET_MGR_SECRET_KEY_NAME}",
SECRET_MGR_USER_NAME = "${var.SECRET_MGR_USER_NAME}",
LOGON_URL = "${var.LOGON_URL}",
PLATFORM_SECRET_NAME = "${var.PLATFORM_SECRET_NAME}"
}
vpc_config_vars = {
subnet_ids = "${var.SUBNET_IDS}",
security_group_ids = "${var.SECURITY_GROUP_IDS}"
}
}
module "lambda" {
source = "git::https://corpsource.io/corp-cloud-platform-team/corpcloudv2/terraform/lambda-modules.git?ref=dev"
lambda_name = var.name
lambda_role = "arn:aws:iam::${var.ACCOUNT}:role/${var.lambda_role}"
lambda_handler = var.handler
lambda_runtime = var.runtime
default_lambda_timeout = var.timeout
ACCOUNT = var.ACCOUNT
vpc_config_vars = merge(
local.vpc_config_vars
)
env = merge(
local.common_tags,
{ DEFAULT_ROLE = "corp-platform" }
)
}
module "lambda_iam" {
source = "git::https://corpsource.io/corp-cloud-platform-team/corpcloudv2/terraform/iam-modules/lambda-iam.git?ref=dev"
lambda_policy = var.lambda_policy
ACCOUNT = var.ACCOUNT
lambda_role = var.lambda_role
}
and inputs.tf
variable "handler" {
type = string
default = "handler.lambda_handler"
}
variable "runtime" {
type = string
default = "python3.8"
}
variable "name" {
type = string
default = "create-SECRET_MGR-entry"
}
variable "timeout"{
type = string
default = "120"
}
variable "lambda_role" {
type = string
default = "create-SECRET_MGR-entry-role"
}
variable "ACCOUNT" {
type = string
default = ""
}
variable "SECRET_MGR_HOST" {
type = string
default = ""
}
variable "SECRET_MGR_SAFE" {
type = string
default = ""
}
variable "SUBNET_IDS" {
type = string
default = ""
}
variable "subnet_ids" {
type = string
default = ""
}
variable "security_group_ids" {
type = string
default = ""
}
variable "SECURITY_GROUP_IDS" {
type = string
default = ""
}
variable "SECRET_MGR_SECRET_KEY_NAME" {
type = string
default = ""
}
variable "SECRET_MGR_USER_NAME" {
type = string
default = ""
}
variable "LOGON_URL" {
type = string
default = ""
}
variable "PLATFORM_SECRET_NAME" {
type = string
default = ""
}
variable "lambda_policy" {
default = "{\"Version\": \"2012-10-17\",\"Statement\": [{\"Sid\":\"VisualEditor0\",\"Effect\":\"Allow\",\"Action\":[\"logs:CreateLogStream\",\"logs:CreateLogGroup\"],\"Resource\":\"*\"},{\"Sid\":\"UseKMSKey\",\"Effect\":\"Allow\",\"Action\":\"kms:Decrypt\",\"Resource\":\"*\"},{\"Sid\":\"GetSecret\",\"Effect\":\"Allow\",\"Action\":\"secretsmanager:GetSecretValue\",\"Resource\":\"*\"},{\"Sid\":\"ConnectToVPC\",\"Effect\":\"Allow\",\"Action\":[\"ec2:CreateNetworkInterface\",\"ec2:DescribeNetworkInterfaces\",\"ec2:DeleteNetworkInterface\"],\"Resource\":\"*\"},{\"Sid\":\"VisualEditor1\",\"Effect\":\"Allow\",\"Action\":\"logs:PutLogEvents\",\"Resource\":\"*\"},{\"Effect\": \"Allow\",\"Action\": [\"logs:*\"],\"Resource\": \"arn:aws:logs:*:*:*\"},{\"Effect\": \"Allow\",\"Action\": [\"s3:GetObject\",\"s3:PutObject\"],\"Resource\": \"arn:aws:s3:::*\"}]}"
}
As you see, main.tf references a module in another project referenced via source argument. The structure of the module project is also:
main.tf
inputs.tf
main.tf
data "archive_file" "lambda_handler" {
type = "zip"
output_path = "lambda_package.zip"
source_dir = "lambda_code/"
}
resource "aws_lambda_function" "lambda_function" {
filename = "lambda_package.zip"
function_name = var.lambda_name
role = var.lambda_role
handler = var.lambda_handler
runtime = var.lambda_runtime
memory_size = 256
timeout = var.default_lambda_timeout
source_code_hash = filebase64sha256("lambda_code/lambda_package.zip")
dynamic "vpc_config" {
for_each = length(keys(var.vpc_config_vars)) == 0 ? [] : [true]
content {
variables = var.vpc_config_vars
}
}
dynamic "environment" {
for_each = length(keys(var.env)) == 0 ? [] : [true]
content {
variables = var.env
}
}
}
inputs.tf
variable "lambda_name" {
type = string
}
variable "lambda_runtime" {
type = string
}
variable "lambda_role" {
type = string
}
variable "default_lambda_timeout" {
type = string
}
variable "lambda_handler" {
type = string
}
variable "vpc_config_vars" {
type = map(string)
default = {}
}
variable "env" {
type = map(string)
default = {}
}
variable "tags" {
default = {
blc = "1539"
costcenter = "54111"
itemid = "obfuscated"
owner = "cloudengineer#company.com"
}
}
variable "ACCOUNT" {
type = string
}
Error when my pipeline runs the project:
Error: Missing required argument
(and 7 more similar warnings elsewhere)
on .terraform/modules/lambda/main.tf line 18, in resource "aws_lambda_function" "lambda_function":
18: content {
The argument "subnet_ids" is required, but no definition was found.
Error: Missing required argument
on .terraform/modules/lambda/main.tf line 18, in resource "aws_lambda_function" "lambda_function":
18: content {
The argument "security_group_ids" is required, but no definition was found.
Error: Unsupported argument
on .terraform/modules/lambda/main.tf line 19, in resource "aws_lambda_function" "lambda_function":
19: variables = var.vpc_config_vars
An argument named "variables" is not expected here.
Oh and I'm passing in the value for subnet_ids and security_group_ids as an environment variable using my gitlab ci file. And log statements confirm that those values are defined.
What is wrong? thank you

Answer 1

You need to pass the required arguments for the vpc_config child block, which are subnet_ids and security_group_ids. You cannot use the entire map variable as it is inside the nested content block. You need to use the equals sign "=" to introduce the argument value.
Try the below code snippet
###################
# Root Module
###################
locals {
vpc_config_vars = {
vpc_config = {
subnet_ids = ["subnet-072297c000a32e200"],
security_group_ids = ["sg-05d06431bd25870b4"]
}
}
}
module "lambda" {
source = "./modules"
...
......
vpc_config_vars = local.vpc_config_vars
}
###################
# Child Module
###################
variable "vpc_config_vars" {
default = {}
}
resource "aws_lambda_function" "lambda_function" {
filename = "lambda_package.zip"
function_name = var.lambda_name
role = var.lambda_role
handler = var.lambda_handler
runtime = var.lambda_runtime
memory_size = 256
timeout = var.default_lambda_timeout
source_code_hash = filebase64sha256("lambda_code/lambda_package.zip")
dynamic "vpc_config" {
for_each = var.vpc_config_vars != {} ? var.vpc_config_vars : {}
content {
subnet_ids = vpc_config.value["subnet_ids"]
security_group_ids = vpc_config.value["security_group_ids"]
}
}
}