# Bonus Hands-On Exercise: Using Variables and Outputs Across Multiple Environments

# Exercise Objective

Participants will create separate variable files for development and production environments, allowing them to provision the same infrastructure with different parameters and outputs. This exercise will help participants understand how to manage multiple environments with Terraform using variable files.

# Steps

# Step 1: Set Up the Project Directory and Base Configuration

Create a New Project Directory (if not already created):
- Open a terminal and create a new directory for the project, then navigate into it:
```
mkdir multi-environment-project
cd multi-environment-project
```
Create a main.tf File:
- In your project directory, create a file named main.tf.
- Define the Azure provider and a Resource Group resource in main.tf:
```
provider "azurerm" {
  features {}
}

resource "azurerm_resource_group" "example" {
  name     = var.resource_group_name
  location = var.location
}
```
- This configuration uses variables to set the name and location of the Resource Group, allowing the values to be customized by environment.
Save the main.tf File.

# Step 2: Define Variables in `variables.tf`

Create a variables.tf File:
- In the same project directory, create a new file named variables.tf.
Define Variables for Resource Group Name and Location:
- In variables.tf, add the following code to define the resource_group_name and location variables:
```
variable "resource_group_name" {
  description = "The name of the resource group"
  type        = string
}

variable "location" {
  description = "The Azure region to deploy resources"
  type        = string
}
```
- These variables will be set differently for each environment using separate variable files.
Save the variables.tf File.

# Step 3: Create Separate Variable Files for Development and Production

Create a dev.tfvars File:
- In your project directory, create a file named dev.tfvars.
- Add the following variable values specific to the development environment:
```
resource_group_name = "dev-resource-group"
location            = "East US"
```
Create a prod.tfvars File:
- In your project directory, create another file named prod.tfvars.
- Add the following variable values specific to the production environment:
```
resource_group_name = "prod-resource-group"
location            = "West US"
```
Save Both Variable Files.

# Step 4: Define Outputs in `outputs.tf`

Create an outputs.tf File:
- In your project directory, create a new file named outputs.tf.

Define Outputs for Resource Group Name and Location:

In outputs.tf, add the following output definitions to display the Resource Group’s name and location:

output "resource_group_name" {
  description = "The name of the resource group"
  value       = azurerm_resource_group.example.name
}

output "resource_group_location" {
  description = "The location of the resource group"
  value       = azurerm_resource_group.example.location
}

Save the outputs.tf File.

# Step 5: Run Terraform Commands for Each Environment

Initialize the Project:
- In the terminal, run the following command to initialize the project and download provider plugins:
```
terraform init
```
Run terraform plan for the Development Environment:
- Use terraform plan with the -var-file flag to preview the changes for the development environment:
```
terraform plan -var-file="dev.tfvars"
```
- Review the output to ensure that Terraform will create a Resource Group with the name dev-resource-group in the "East US" region.
Run terraform apply for the Development Environment:
- Apply the configuration using the dev.tfvars file to create the Resource Group for development:
```
terraform apply -var-file="dev.tfvars"
```
- Type yes when prompted to confirm the apply operation.
- After the apply completes, note the output values for resource_group_name and resource_group_location, which should reflect the development environment settings.
Repeat for the Production Environment:
- Run terraform plan and terraform apply using the prod.tfvars file:
```
terraform plan -var-file="prod.tfvars"
terraform apply -var-file="prod.tfvars"
```
- Confirm the creation of the Resource Group for the production environment, which should have the name prod-resource-group and location "West US".

# Step 6: Verify Resource Groups in Azure Portal

Log in to the Azure Portal:
- Go to the Azure Portal.
Navigate to Resource Groups:
- Check that both dev-resource-group and prod-resource-group have been created in the respective regions specified in dev.tfvars and prod.tfvars.

# Verification

Confirm Environment-Specific Resources:
- Ensure that the Resource Groups in Azure match the names and locations specified in dev.tfvars and prod.tfvars.
Confirm Output Values:
- Verify that the output values displayed in the terminal during terraform apply reflect the correct resource group name and location for each environment.