Introduction

Infrastructure as Code using Terraform - Module Development

Prerequisites

• Azure CLI installed.

  Assumes CLI Version = azure-cli (2.31.0)

• HashiCorp Terraform installed.

  Version Manager: tfenv

  export VER="1.1.1"
  wget https://releases.hashicorp.com/terraform/${VER}/terraform_${VER}_linux_amd64.zip
  unzip terraform_${VER}_linux_amd64.zip
  sudo mv terraform /usr/local/bin/

Setup Terraform Environment Variables

Generate Azure client id and secret.

After creating a Service Principal you MUST add API access for Windows Azure Active Directory and enable the following permissions

• Read and write all applications
• Sign in and read user profile

# Create a Service Principal
Subscription=$(az account show --query id -otsv)
az ad sp create-for-rbac --name "Terraform-Principal" --role="Owner" --scopes="/subscriptions/$Subscription" -ojson

# Expected Result
{
  "appId": "00000000-0000-0000-0000-000000000000",
  "displayName": "Terraform-Principal",
  "name": "http://Terraform-Principal",
  "password": "0000-0000-0000-0000-000000000000",
  "tenant": "00000000-0000-0000-0000-000000000000"
}

appId -> Client id. password -> Client secret. tenant -> Tenant id.

Export environment variables to configure the Azure Terraform provider.

A great tool to do this automatically with is direnv.

export ARM_SUBSCRIPTION_ID="SUBSCRIPTION_ID"
export ARM_TENANT_ID="TENANT_ID"
export ARM_CLIENT_ID="CLIENT_ID"
export ARM_CLIENT_SECRET="CLIENT_SECRET"
export TF_VAR_client_id=${ARM_CLIENT_ID}
export TF_VAR_client_secret=${ARM_CLIENT_SECRET}

TF_VAR_remote_state_account="STORAGE_ACCOUNT"
TF_VAR_remote_state_container="remote-state-container"

Setup Terraform Azure Backend State

Terraform requires state to be stored in some location. This state can be stored in Azure Blob if desired. (optional)

Execute the init-backend-state.sh script to create the required Azure Resources.

• Resource Group (or existing) to hold resources
• Storage Account (or existing) for blob storage
• Storage Container (or existing) for state blob
• Key Vault (or existing) for storage account key

ResourceGroup="tfstate"
StorageAccount="tfstate"  # Must be unique
KeyVault="tfstate"
./scripts/init-backend-state.sh $ResourceGroup $StorageAccount $KeyVault

# Expected Result
Creating Terraform Backend Store
------------------------------------
Logging in and setting subscription...
Creating the Resource Group...
Creating the Storage Account...
Retrieving the Storage Account Key...
Creating the Storage Account Container...
Creating the Key Vault...
Adding Storage Key to Vault...
------------------------------------

TF_VAR_remote_state_account=tfstate
TF_VAR_remote_state_container=remote-state-container

Run the following command to initialize Terraform to store its state into Azure Storage:
terraform init \
  -backend-config="storage_account_name=tfstate" \
  -backend-config="container_name=remote-state-container" \
  -backend-config="access_key=$(az keyvault secret show --name tfstate-storage-key --vault-name tfstate --query value -o tsv)" \
  -backend-config="key=terraform-ref-architecture-tfstate"

Getting Started

1. Testing with Task Runner (mage)

iac-terraform task runner.

Targets:
  all              A build step that runs all tests.
  check            Validate both Terraform code and Go code.
  clean            Remove temporary build and test files.
  lintGO           Lint check Go and fail if files are not not formatted properly.
  lintTF           Lint check Terraform and fail if files are not formatted properly.
  test             Execute Module Tests and fail if a test fails.
  testSimpleWeb    Execute Integration Tests for the simpleweb sample.
  testWebData      Execute Integration Tests for the webdata sample.

2. Deploying Sample Templates

• simpleweb - This template deploys a simple Web App with Containers
• webdata - This template deploys a Web App with Containers with Cosmos DB Integration

# Change directory to Samples
cd samples/{sample}

# Initialize the Modules
terraform init

# Test the plan
terraform plan

# Apply the Plan
terraform apply

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This repo was created for personal learning objectives. Concepts and terraform modules have been modified from the following projects.

• Project Cobalt
• Project Bedrock
• Innovation Norway
• Terraform Azure