When you are are managing the multiple infrastructure/Resources you can utilize the workspace utility.
On real-time scenario, you may be end-up with multiple projects like dev,test,prod. Those workspace are separated and those having a separate variables.
using single.tf file you can manage a mutiple environments.
Get help from terraform workspace.
[root@terraform workspace]# terraform workspace --help
Usage: terraform [global options] workspace
new, list, show, select and delete Terraform workspaces.
Subcommands:
delete Delete a workspace
list List Workspaces
new Create a new workspace
select Select a workspace
show Show the name of the current workspace
We have created a three workspace
[root@terraform workspace]# terraform workspace new dev
Created and switched to workspace "dev"!
You're now on a new, empty workspace. Workspaces isolate their state,
so if you run "terraform plan" Terraform will not see any existing state
for this configuration.
[root@terraform workspace]# terraform workspace new test
Created and switched to workspace "test"!
You're now on a new, empty workspace. Workspaces isolate their state,
so if you run "terraform plan" Terraform will not see any existing state
for this configuration.
[root@terraform workspace]# terraform workspace new prod
Created and switched to workspace "prod"!
You're now on a new, empty workspace. Workspaces isolate their state,
so if you run "terraform plan" Terraform will not see any existing state
for this configuration.
terraform workspace show command will show the current workspace directory.
[root@terraform workspace]# terraform workspace show
prod
terraform workspace list command will list all the workspace.
[root@terraform workspace]# terraform workspace list
default
dev
* prod
test
When you create a workspace, terraform.tfstate.d directory will be created automatically and all the workspace are inside this directory.
[root@terraform workspace]# ll
total 8
-rw-r--r-- 1 root root 271 Feb 18 08:38 ec2.tf
-rw-r--r-- 1 root root 142 Feb 16 06:52 resource.tf
drwxr-xr-x 5 root root 41 Feb 22 17:27 terraform.tfstate.d
[root@terraform workspace]# cd terraform.tfstate.d/
[root@terraform terraform.tfstate.d]# ll
total 0
drwxr-xr-x 2 root root 6 Feb 22 17:26 dev
drwxr-xr-x 2 root root 6 Feb 22 17:27 prod
drwxr-xr-x 2 root root 6 Feb 22 17:27 test
We updated the .tf file and provided the instance_type as per the workspace.
[root@terraform workspace]# vi ec2.tf
[root@terraform workspace]# terraform validate
Success! The configuration is valid.
[root@terraform workspace]# cat ec2.tf
resource "aws_instance" "webserver" {
ami = "ami-06e85d4c3149db26a"
instance_type = lookup(var.instance_type,terraform.workspace)
}
variable "instance_type" {
type = map
default = {
prod = "t3.xlarge"
dev = "t3.large"
test = "t3.micro"
}
}
Here i switched between the workspaces and tried the terraform plan command
According to the workspace, the instance_type has been changed. This means you can use the different variables to every workspace.
[root@terraform workspace]# terraform workspace select prod
[root@terraform workspace]# terraform workspace show
prod
[root@terraform workspace]# terraform plan | grep -i instance_type
+ instance_type = "t3.xlarge"
[root@terraform workspace]# terraform workspace select dev
Switched to workspace "dev".
[root@terraform workspace]# terraform workspace show
dev
[root@terraform workspace]# terraform plan | grep -i instance_type
+ instance_type = "t3.large"
[root@terraform workspace]# terraform workspace select test
Switched to workspace "test".
[root@terraform workspace]# terraform plan | grep -i instance_type
+ instance_type = "t3.micro"
You can apply and verify from your end.
You did a great Job!!!