The below is specific to terraform .11 and works with .12
Below is the code I am using. It is a data block to get Image details from Azure shared Image Gallery.
I have a variable input parameter for image_version
I can give image_version as a particular version ( like * 1.0.1 or 1.0.2 * ) or can give input as * latest *
If you see the output block in below code , if the image_version is given as latest the 1st data section will be executed and latest image will be given as output
And if I give input NOT as latest - the 2nd data section will be executed and give that particular image ID will be given as output
So this output , I am using for virtual machine creation
### 1. latest section ####
data "azurerm_shared_image" "centos7" {
name = "centos"
gallery_name = "centos_galleries"
resource_group_name = "centos-galleries-rg"
}
### 2. image version number section ####
data "azurerm_shared_image_version" "centos7" {
name = "1.0.1" ## [ This block fails when provided a dummy number ]
image_name = "centos"
gallery_name = "centos_galleries"
resource_group_name = "centos-galleries-rg"
}
output "id" {
value = "${var.image_version == "latest" ? data.azurerm_shared_image.centos7.id : data.azurerm_shared_image_version.centos7.id}"
}
Now the issue is, in 2nd data section I am giving name = 1.0.1 - which should be an existing version in Shared Image gallery.
If I gives a non existing version number in my code ( say name = 10.10.10 ) and gives my input image_version = latest , ideally only the 1st data section should be evaluated and should be working fine - but with terraform 11 - the 2nd data section also gets evaluated and it is failing with the name = 10.10.10 version is not existing. Here I gave input image_version = latest - still it is failing
So is there a way I can conditionally exclude a complete data section or is there a better way I can re-write this code?
Related
I'm trying to use output values from a 2nd workspace in my current one.
For example:
data "tfe_outputs" "EKS" {
organization = "EKS_Deploy"
workspace = "EKS_Deploy"
}
Then I need EKS cluster ID in one of my modules from that 2nd workspace (I already set up outputs):
2nd workspace
output "eks_cluster_id" {
description = "EKS Cluster ID"
value = module.eks-ssp.eks_cluster_id
}
1st workspace
eks_cluster_id = data.tfe_outputs.EKS.eks_cluster_id
But, running a terraform apply in the second workspace throws this:
Error: Unsupported attribute
on main.tf line 22, in data "aws_eks_cluster" "cluster":
name = data.tfe_outputs.EKS.eks_cluster_id
This object has no argument, nested block, or exported attribute named "eks_cluster_id".
This is strange to me, since I can see the correct output value in my 2nd workspace, ie. it shows a proper output. So I'm guessing I'm calling it wrong somehow. What could it be?
I am trying to create a single GCP Workflows using Terraform (Terraform Workflows documentation here). To create a workflow, I have defined the desired steps and order of execution using the Workflows syntax in YAML (can also be JSON).
I have around 20 different jobs and each of theses jobs are on different .yaml files under the same folder, workflows/. I just want to loop over the /workflows folder and have a single .yaml file to be able to create my resource. What would be the best way to achieve this using Terraform? I read about for_each but it was primarily used to loop over something to create multiple resources rather than a single resource.
workflows/job-1.yaml
- getCurrentTime:
call: http.get
args:
url: https://us-central1-workflowsample.cloudfunctions.net/datetime
result: currentDateTime
workflows/job-2.yaml
- readWikipedia:
call: http.get
args:
url: https://en.wikipedia.org/w/api.php
query:
action: opensearch
search: ${currentDateTime.body.dayOfTheWeek}
result: wikiResult
main.tf
resource "google_workflows_workflow" "example" {
name = "workflow"
region = "us-central1"
description = "Magic"
service_account = google_service_account.test_account.id
source_contents = YAML FILE HERE
Terraform has a function fileset which allows a configuration to react to files available on disk alongside its definition. You can use this as a starting point for constructing a suitable expression for for_each:
locals {
workflow_files = fileset("${path.module}/workflows", "*.yaml")
}
It looks like you'd also need to specify a separate name for each workflow, due to the design of the remote system, and so perhaps you'd decide to set the name to be the same as the filename but with the .yaml suffix removed, like this:
locals {
workflows = tomap({
for fn in local.workflow_files :
substr(fn, 0, length(fn)-5) => "${path.module}/workflows/${fn}"
})
}
This uses a for expression to project the set of filenames into a map from workflow name (trimmed filename) to the path to the specific file. The result then would look something like this:
{
job-1 = "./module/workflows/job-1.yaml"
job-2 = "./module/workflows/job-2.yaml"
}
This now meets the requirements for for_each, so you can refer to it directly as the for_each expression:
resource "google_workflows_workflow" "example" {
for_each = local.workflows
name = each.key
region = "us-central1"
description = "Magic"
service_account = google_service_account.test_account.id
source_contents = file(each.value)
}
Your question didn't include any definition for how to populate the description argument, so I've left it set to hard-coded "Magic" as in your example. In order to populate that with something reasonable you'd need to have an additional data source for that, since what I wrote above is already making full use of the information we get just from scanning the content of the directory.
resource "google_workflows_workflow" "example" {
# count for total iterations
count = 20
name = "workflow"
region = "us-central1"
description = "Magic"
service_account = google_service_account.test_account.id
# refer to file using index, index starts from 0
source_contents = file("${path.module}/workflows/job-${each.index}.yaml")
}
I have been trying to conditionally use a module from the root module, so that for certain environments this module is not created. Many people claim that by setting the count in the module to either 0 or 1 using a conditional does the trick.
module "conditionally_used_module" {
source = "./modules/my_module"
count = (var.create == true) ? 1 : 0
}
However, this changes the type of conditionally_used_module: instead of an object (or map) we will have a list (or tuple) containing a single object. Is there another way to achieve this, that does not imply changing the type of the module?
To conditionally create a module you can use a variable, lets say it's called create_module in the variables.tf file of the module conditionally_used_module.
Then for every resource inside the conditionally_used_module module you will use the count to conditionally create or not that specific resource.
The following example should work and provide you with the desired effect.
# Set a variable to know if the resources inside the module should be created
module "conditionally_used_module" {
source = "./modules/my_module"
create_module = var.create
}
# Inside the conditionally_used_module file
# ( ./modules/my_module/main.tf ) most likely
# for every resource inside use the count to create or not each resource
resource "resource_type" "resource_name" {
count = var.create_module ? 1 : 0
... other resource properties
}
I used this in conjunction with workspaces to build a resource only for certain envs. The advantage is for me that I get a single terraform.tfvars file to control the all the environments structure for a project.
Inside main.tf:
workspace = terraform.workspace
#....
module "gcp-internal-lb" {
source = "../../modules/gcp-internal-lb"
# Deploy conditionally based on deploy_internal_lb variable
count = var.deploy_internal_lb[local.workspace] == true ? 1 : 0
# module attributes here
}
Then in variables.tf
variable "deploy_internal_lb" {
description = "Set to true if you want to create an internal LB"
type = map(string)
}
And in terraform.tfvars:
deploy_internal_lb = {
# DEV
myproject-dev = false
# QA
myproject-qa = false
# PROD
myproject-prod = true
}
I hope it helps.
I have a case where I have to create an aws_vpc resource if the user does not provide vpc id. After that I am supposed to create resources with that VPC.
Now, I am applying conditionals while creating an aws_vpc resource. For example, only create VPC if existing_vpc is false:
count = "${var.existing_vpc ? 0 : 1}"
Next, for example, I have to create nodes in the VPC. If the existing_vpc is true, use the var.vpc_id, else use the computed VPC ID from aws_vpc resource.
But, the issue is, if existing_vpc is true, aws_vpc will not create a new resource and the ternary condition is anyways trying to check if the aws_vpc resource is being created or not. If it doesn't get created, terraform errors out.
An example of the error when using conditional operator on aws_subnet:
Resource 'aws_subnet.xyz-subnet' not found for variable 'aws_subnet.xyz-subnet.id'
The code resulting in the error is:
subnet_id = "${var.existing_vpc ? var.subnet_id : aws_subnet.xyz-subnet.id}"
If both things are dependent on each other, how can we create conditional resources and assign values to other configuration based on them?
You can access dynamically created modules and resources as follows
output "vpc_id" {
value = length(module.vpc) > 0 ? module.vpc[*].id : null
}
If count = 0, output is null
If count > 0, output is list of vpc ids
If count = 1 and you want to receive a single vpc id you can specify:
output "vpc_id" {
value = length(module.vpc) > 0 ? one(module.vpc).id : null
}
The following example shows how to optionally specify whether a resource is created (using the conditional operator), and shows how to handle returning output when a resource is not created. This happens to be done using a module, and uses an object variable's element as a flag to indicate whether the resource should be created or not.
But to specifically answer your question, you can use the conditional operator as follows:
output "module_id" {
value = var.module_config.skip == true ? null : format("%v",null_resource.null.*.id)
}
And access the output in the calling main.tf:
module "use_conditionals" {
source = "../../scratch/conditionals-modules/m2" # << Change to your directory
a = module.skipped_module.module_id # Doesn't exist, so might need to handle that.
b = module.notskipped_module.module_id
c = module.default_module.module_id
}
Full example follows. NOTE: this is using terraform v0.14.2
# root/main.tf
provider "null" {}
module "skipped_module" {
source = "../../scratch/conditionals-modules/m1" # << Change to your directory
module_config = {
skip = true # explicitly skip this module.
name = "skipped"
}
}
module "notskipped_module" {
source = "../../scratch/conditionals-modules/m1" # << Change to your directory
module_config = {
skip = false # explicitly don't skip this module.
name = "notskipped"
}
}
module "default_module" {
source = "../../scratch/conditionals-modules/m1" # << Change to your directory
# The default position is, don't skip. see m1/variables.tf
}
module "use_conditionals" {
source = "../../scratch/conditionals-modules/m2" # << Change to your directory
a = module.skipped_module.module_id
b = module.notskipped_module.module_id
c = module.default_module.module_id
}
# root/outputs.tf
output skipped_module_name_and_id {
value = module.skipped_module.module_name_and_id
}
output notskipped_module_name_and_id {
value = module.notskipped_module.module_name_and_id
}
output default_module_name_and_id {
value = module.default_module.module_name_and_id
}
the module
# m1/main.tf
resource "null_resource" "null" {
count = var.module_config.skip ? 0 : 1 # If skip == true, then don't create the resource.
provisioner "local-exec" {
command = <<EOT
#!/usr/bin/env bash
echo "null resource, var.module_config.name: ${var.module_config.name}"
EOT
}
}
# m1/variables.tf
variable "module_config" {
type = object ({
skip = bool,
name = string
})
default = {
skip = false
name = "<NAME>"
}
}
# m1/outputs.tf
output "module_name_and_id" {
value = var.module_config.skip == true ? "SKIPPED" : format(
"%s id:%v",
var.module_config.name,
null_resource.null.*.id
)
}
output "module_id" {
value = var.module_config.skip == true ? null : format("%v",null_resource.null.*.id)
}
The current answers here are helpful when you are working with more modern versions of terraform, but as noted by OP here they do not work when you are working with terraform < 0.12 (If you're like me and still dealing with these older versions, I am sorry, I feel your pain.)
See the relevant issue from the terraform project for more info on why the below is necessary with the older versions.
but to avoid link rot, I'll use the OPs example subnet_id argument using the answers in the github issue.
subnet_id = "${element(compact(concat(aws_subnet.xyz-subnet.*.id, list(var.subnet_id))),0)}"
From the inside out:
concat will join the splat output list to list(var.subnet_id) -- per the background link 'When count = 0, the "splat syntax" expands to an empty list'
compact will remove the empty item
element will return your var.subnet_id only when compact recieves the empty splat output.
I have written a Terraform script to create a few Azure Virtual Machines.
The number of VMs created is based upon a variable called type in my .tfvars file:
type = [ "Master-1", "Master-2", "Master-3", "Slave-1", "Slave-2", "Slave-3" ]
My variables.tf file contains the following local:
count_of_types = "${length(var.type)}"
And my resources.tf file contains the code required to actual create the relevant number of VMs from this information:
resource "azurerm_virtual_machine" "vm" {
count = "${local.count_of_types}"
name = "${replace(local.prefix_specific,"##TYPE##",var.type[count.index])}-VM"
location = "${azurerm_resource_group.main.location}"
resource_group_name = "${azurerm_resource_group.main.name}"
network_interface_ids = ["${azurerm_network_interface.main.*.id[count.index]}"]
vm_size = "Standard_B2ms"
tags = "${local.tags}"
Finally, in my output.tf file, I output the IP address of each server:
output "public_ip_address" {
value = ["${azurerm_public_ip.main.*.ip_address}"]
}
I am creating a Kubernetes cluster with 1x Master and 1x Slave VM. For this purpose, the script works fine - the first IP output is the Master and the second IP output is the Slave.
However, when I move to 8+ VMs in total, I'd like to know which IP refers to which VM.
Is there a way of amending my output to include the type local, or just the server's hostname alongside the Public IP?
E.g. 54.10.31.100 // Master-1.
Take a look at formatlist (which is one of the functions for string manipulations) and can be used to iterate over the instance attributes and list tags and other attributes of interest.
output "ip-address-hostname" {
value = "${
formatlist(
"%s:%s",
azurerm_public_ip.resource_name.*.fqdn,
azurerm_public_ip.resource_name.*.ip_address
)
}"
}
Note this is just a draft pseudo code. You may have to tweak this and create additional data sources in your TF file for effective enums
More reading available - https://www.terraform.io/docs/configuration/functions/formatlist.html
Raunak Jhawar's answer pointed me in the right direction, and therefore got the green tick.
For reference, here's the exact code I used in the end:
output "public_ip_address" {
value = "${formatlist("%s: %s", azurerm_virtual_machine.vm.*.name, azurerm_public_ip.main.*.ip_address)}"
}
This resulted in the following output: