Reading environment variables in a terraform file

Working with terraform a lot of times you need to deal with environment variables, be it reading credentials or externalising some other…

The right way to DevOps

Working with terraform a lot of times you need to deal with environment variables, be it reading credentials or externalising some other configuration.

Let’s see how to do that.

1. Add TF_VAR suffix to your regular environment variables.

i.e YOUR_VARIABLE should be TF_VAR_YOUR_VARIABLE

Instead of changing the name of the existing environment variable create a new one.

TF_VAR_AWS_ACCESS_KEY_ID=$AWS_ACCESS_KEY_ID

2. Declare a variable with the same name as the part after the suffix inside the terraform file.

TF_VAR_AWS_ACCESS_KEY_ID is the environment variable

We will declare the variable inside the file as :

variable "AWS_ACCESS_KEY_ID" {}

3. Automatically this variable will read the environment variable TF_VAR_AWS_ACCESS_KEY_ID

4. The variable can be used anywhere inside the file this way:

Before version 12

provider "aws" {      access_key = "${var.AWS_ACCESS_KEY_ID}"      secret_key = "${var.AWS_SECRET_ACCESS_KEY}"      region = "us-east-1"}

Version 12 onwards

provider "aws" {      access_key = var.AWS_ACCESS_KEY_ID      secret_key = var.AWS_SECRET_ACCESS_KEY      region = "us-east-1"}

Refer to the actual code here.

Happy Learning:)