I'm using a for_each to loop through the following variable:
networks = {
network1 = {
name = "NETWORK1"
},
network2 = {
name = "NETWORK2"
}
}
There is a dependency on the underlying API that a second network can only be created if the previous one has been created.
Therefore I wanted to use a depends_on in the below snippet:
resource "virtual_network" "network" {
depends_on = []
for_each = var.networks
parameters {
payload {
name = each.value.name
}
}
}
How can I make the network creation dependent on the previous iteration of the for_each loop?
Related
I have created some subnets. I want to share those subnets with other accounts. For that I need to retrieve the ARN of the subnets.
I am able to get a list of ARNs like this
data "aws_subnets" "dev_subnet" {
filter {
name = "vpc-id"
values = [module.vpc.vpc_id]
}
tags = {
Environment = "dev-*"
}
}
data "aws_subnet" "dev_subnet" {
for_each = toset(data.aws_subnets.dev_subnet.ids)
id = each.value
}
output "dev_subnet_arns" {
value = [for s in data.aws_subnet.dev_subnet : s.arn]
}
This results in
+ dev_subnet_arns = [
+ "arn:aws:ec2:ca-central-1:0097747:subnet/subnet-013987fd9651c3545",
+ "arn:aws:ec2:ca-central-1:0477747:subnet/subnet-015d76b264280321a",
+ "arn:aws:ec2:ca-central-1:0091747:subnet/subnet-026cd0402fe283c33",
]
Now I want to take the list of arns of the subnets and associate them with the resource_share_arn
What Im trying is something like this
resource "aws_ram_resource_association" "example" {
for_each = toset(data.aws_subnets.dev_subnet.ids)
resource_arn = each.value
resource_share_arn = aws_ram_resource_share.share_subnets_with_dev_account.arn
}
But this fails since it only gets the subnets ids and thats wrong
error associating RAM Resource Share: MalformedArnException: The specified resource ARN subnet-0c4afd736c18b3c28 is not valid. Verify the ARN and try again.
This also fails
resource "aws_ram_resource_association" "example" {
for_each = toset(data.aws_subnets.dev_subnet.arn)
resource_arn = each.value
resource_share_arn = aws_ram_resource_share.share_subnets_with_dev_account.arn
}
since arn is not an attribute. What am I missing here ?
You need to loop over the ARNs of the subnets and pass the ARN value for the resource_arn:
resource "aws_ram_resource_association" "example" {
for_each = toset([for s in data.aws_subnet.dev_subnet : s.arn])
resource_arn = each.value
resource_share_arn = aws_ram_resource_share.share_subnets_with_dev_account.arn
}
Or another solution would be:
resource "aws_ram_resource_association" "example" {
for_each = toset(values(data.aws_subnet.dev_subnet)[*].arn)
resource_arn = each.value
resource_share_arn = aws_ram_resource_share.share_subnets_with_dev_account.arn
}
I have a terraform file with the following contents:
resource "aws_iam_group" "developers" {
name = each.value
for_each = toset(var.groups)
}
resource "aws_iam_group_membership" "developers_team" {
name = "Developers Team"
users = [each.value]
for_each = toset(var.group_users)
group = aws_iam_group.developers.name
}
I would like to reference aws_iam_group from aws_iam_group_membership. How would I do that? The current terraform file is not working.
I tried this:
group = aws_iam_group.developers[each.value] //This will not work since it uses the for_each of
its own code block
The variable file is as below:
variable "groups" {
type = list(string)
default = [
"terraform_group1",
"terraform_group2",
"terraform_group3",
]
}
variable "group_users" {
type = list(string)
default = [
"terraform_test_user1",
"terraform_test_user2"
]
}
Edit:
I tried the below, but it is not working
resource "aws_iam_group_membership" "developers_team" {
name = "Developers Team"
users = [for group_user in var.group_users : group_user]
for_each = toset(var.groups)
group = aws_iam_group.developers[each.key]
}
Apparently, this is working:
resource "aws_iam_group" "developer" {
name = "truedeveloper"
}
resource "aws_iam_group_membership" "developers_team" {
name = "Developers_Team"
users = [for group_user in var.group_users : group_user]
for_each = toset(var.groups)
group = aws_iam_group.developer.name
}
I am new to terraform and I'm trying to create a VPC with multiple subnets and adding route tables to all those subnets in a for loop manner.
VPC: 10.207.0.0/16
There's number_of_subnets which will create subnets like this: 10.207.x.0/24
This code works fine:
variable "region" {
default = "us-east-1"
}
variable "availability_zone" {
default = "us-east-1a"
}
variable "cidr_block" {
default = "207"
}
variable "number_of_subnets" {
default = 5
}
provider "aws" {
region = var.region
}
resource "aws_vpc" "test_vpc" {
cidr_block = "10.${var.cidr_block}.0.0/16"
instance_tenancy = "default"
enable_dns_support = true
enable_dns_hostnames = true
tags = {
Name = "test_vpc_${var.cidr_block}"
}
}
resource "aws_subnet" "test_subnets" {
count = var.number_of_subnets
vpc_id = aws_vpc.test_vpc.id
cidr_block = "10.${var.cidr_block}.${count.index+1}.0/24" # start from x.x.1.0/24
availability_zone = var.availability_zone
map_public_ip_on_launch = false
tags = {
Name = "test_subnet_${var.cidr_block}_${count.index+1}"
}
}
Now if I try to add this code to the bottom of the same file (everything is in one file called main.tf) to get the subnets and add route table to each:
# get all subnet IDs
data "aws_subnets" "q_subnets" {
filter {
name = "vpc-id"
values = [aws_vpc.test_vpc.id]
}
}
# add route table to all subnets
resource "aws_route_table_association" "rt_assoc_subnet" {
depends_on = [aws_subnet.test_subnets]
for_each = toset(data.aws_subnets.q_subnets.ids)
subnet_id = each.value
route_table_id = aws_route_table.test_rt.id
}
and run terraform apply it will give this error:
invalid for_each argument...
The "for_each" value depends on resource attribute that cannot be deteremined until apply,...
which doesn't make scense. First create vpc, then subnet, then get all subnets...
I also tried depends_on and didn't help.
How would I write this to make it work?
Any help is appreciated.
UPDATE1:
I tried to use aws_subnet.test_subnets.*.id instead of data and it still gives depencendy error:
variable "region" {
default = "us-east-1"
}
variable "availability_zone" {
default = "us-east-1a"
}
variable "cidr_block" {
default = "207"
}
variable "number_of_subnets" {
default = 5
}
provider "aws" {
region = var.region
}
resource "aws_vpc" "test_vpc" {
cidr_block = "10.${var.cidr_block}.0.0/16"
instance_tenancy = "default"
enable_dns_support = true
enable_dns_hostnames = true
tags = {
Name = "test_vpc_${var.cidr_block}"
}
}
resource "aws_route_table" "test_rt" {
vpc_id = aws_vpc.test_vpc.id
route = []
tags = {
Name = "test_rt_${var.cidr_block}"
}
}
resource "aws_subnet" "test_subnets" {
count = var.number_of_subnets
vpc_id = aws_vpc.test_vpc.id
cidr_block = "10.${var.cidr_block}.${count.index+1}.0/24" # start from x.x.1.0/24
availability_zone = var.availability_zone
map_public_ip_on_launch = false
tags = {
Name = "test_subnet_${var.cidr_block}_${count.index+1}"
}
}
output "subnets" {
value = aws_subnet.test_subnets.*.id
}
# add route table to all subnets
resource "aws_route_table_association" "rt_assoc_subnet" {
depends_on = [aws_subnet.test_subnets]
for_each = toset(aws_subnet.test_subnets.*.id)
subnet_id = each.value
route_table_id = aws_route_table.test_rt.id
}
is there another way to pass the subnets to aws_route_table_association without getting dependency error?
Since you are using count, it is very hard to make count work with for_each. It would be better to continue using count for route table association as well. If you decide to go down that route, the only change you need is:
resource "aws_route_table_association" "rt_assoc_subnet" {
count = var.number_of_subnets
subnet_id = aws_subnet.test_subnets.*.id[count.index]
route_table_id = aws_route_table.test_rt.id
}
This will work as intended. However, if you must use for_each I would suggest defining a variable that could be used with it in all the resources you are now using count. If you really want to use for_each with the current code, then you can use the -target option [1]:
terraform apply -target=aws_vpc.test_vpc -target=aws_route_table.test_rt -target=aws_subnet.test_subnets
When running this command, this will be shown in the command output:
│ Warning: Resource targeting is in effect
│
│ You are creating a plan with the -target option, which means that the result of this plan may not represent all of the changes requested by the current
│ configuration.
│
│ The -target option is not for routine use, and is provided only for exceptional situations such as recovering from errors or mistakes, or when Terraform
│ specifically suggests to use it as part of an error message.
After the targeted resources are created, you could re-run terraform apply and it should create the route table associations.
[1] https://www.terraform.io/cli/commands/plan#target-address
Need your kind help. I am stuck with the following resource creation. Using Terraform v1.0.6
I need to create appropriate subnets dynamically in two VPCs
variables.tf
vpc_resource_networks = {
pnw-01 = [
[
{
subnet_name = "wb-01"
subnet_ip = "10.58.72.0/25"
description = "WEB01"
index = 0
},
{
subnet_name = "wb-02"
subnet_ip = "10.58.72.128/25"
description = "WEB02"
index = 1
}
],
[
{
subnet_name = "wb-01"
subnet_ip = "10.58.80.0/25"
description = "WEB01"
index = 0
},
{
subnet_name = "web-02"
subnet_ip = "10.58.72.128/25"
description = "WEB02"
index = 1
}
]
]
}
main.tf
locals {
wlb_net = element(keys(var.vpc_resource_networks), 0)
}
resource "aws_subnet" "wlb" {
count = length(module.aws_vpc_app_resource)
vpc_id = element(module.aws_vpc_app_resource.*.vpc_id, count.index)
dynamic "subnet_group" {
for_each = var.vpc_resource_networks[local.wlb_net][count.index]
content {
dynamic "subnet" {
for_each = subnet_group.value
content {
cidr_block = subnet.subnet_ip
availability_zone = element(var.azs, subnet.index)
tags = {
Name = subnet.subnet_name
}
}
}
}
}
I intend to create subnets dynamically which is var.vpc_resource_networks.pnw01[0] should be on one vpc and other index on another VPC.
The above block returns
dynamic “subnet_group” {
Blocks of type “subnet_group” are not expected here.
Please assist
Looking at the resource definition of aws_subnet, I can see that, as the error message suggests, there's no property for a "subnet_group".
There are several different resource types that are subnet groups though for different services; such as DMS, DocumentDB, DAX, Elasticache, MemoryDB, Neptune, RDS, and Redshift. Search the term "subnet_group" on the left panel within the provider page.
Perhaps an AWS expert can comment here but I believe you're trying to do two things in one motion here.
First you should create the subnets and define their ranges, then you should create subnet groups that need access to different subnets for a particular service.
Here's some more information on subnets and subnet groups.
I am trying to work out how to iterate over nested variables from a complex object given in the following tfvars file using Terraform 0.12.10:
example.tfvars
virtual_network_data = {
1 = {
product_instance_id = 1
location = "somewhere"
address_space = ["192.168.0.0/23"]
dns_servers = []
custom_tags = {"test":"test value"}
subnets = [
{
purpose = "mgmt"
newbits = 4
item = 0
},
{
purpose = "transit"
newbits = 4
item = 1
}
]
}
}
example.tf
variable "virtual_network_data" {} #Data comes from example.tfvars
variable "resource_group_name" {
default = "my_resource_group"
}
variable "virtual_network_name" {
default = "my_virtual_network"
}
####
resource "azurerm_subnet" "pool" {
for_each = var.virtual_network_data
name = format("%s%s%02d", "subnet_", s.purpose, s.item)
resource_group_name = var.resource_group_name
virtual_network_name = var.virtual_network_name
address_prefix = cidrsubnet(each.value["address_space"], s.newbits, s.item)
}
In example.tf I can use each.value["address_space"] to get to the top level variables, but I can't work out how to get to the items in subnets (s.purpose, s.item & s.newbits).
I have used dynamic blocks, as part of a parent resource (below), which works but in this case, I need to move the subnet into its own resource. Simply put, how do I get the first for_each to behave like the second for_each in the dynamic block?
resource "azurerm_virtual_network" "pool" {
for_each = var.virtual_network_data
name = format("%s%02d", local.resource_name, each.key)
resource_group_name = var.resource_group_name
location = each.value["location"]
address_space = each.value["address_space"]
dns_servers = each.value["dns_servers"]
tags = merge(local.tags, each.value["custom_tags"])
dynamic "subnet" {
for_each = [for s in each.value["subnets"]: {
name = format("%s%s%02d", "subnet_", s.purpose, s.item)
prefix = cidrsubnet(element(each.value["address_space"],0), s.newbits, s.item)
}]
content {
name = subnet.value.name
address_prefix = subnet.value.prefix
}
}
}
Cheeky bonus, is there a way to replace s.item with something like each.key or count.index?
TIA
The technique in this situation is to use other Terraform language features to transform your collection to be a suitable shape for the for_each argument: one element per resource instance.
For nested data structures, you can use flatten in conjunction with two or more for expressions to produce a flat data structure with one element per nested object:
locals {
network_subnets = flatten([
for network_key, network in var.virtual_network_data : [
for subnet in network.subnets : {
network_key = network_key
purpose = subnet.purpose
parent_cidr_block = network.address_space[0]
newbits = subnet.newbits
item = subnet.item
}
]
])
}
Then you can use local.network_subnets as the basis for repetition:
resource "azurerm_subnet" "pool" {
# Each instance must have a unique key, so we'll construct one
# by combining the network key, the subnet "purpose", and the "item".
for_each = {
for ns in local.network_subnets : "${ns.network_key}.${ns.purpose}${ns.item}" => ns
}
name = format("%s%s%02d", "subnet_", each.value.purpose, each.value.item)
resource_group_name = var.resource_group_name
virtual_network_name = var.virtual_network_name
address_prefix = cidrsubnet(each.value.parent_cidr_block, each.value.newbits, each.value.item)
}
There's a similar example in the flatten documentation, as some additional context.
As alternative to flatten trick, you may for_each resource by first parameter inside nested module, then for_each this module by second parameter.