Enterprise Landing Zone (ELZ)

Welcome to the Enterprise Landing Zone!

This project is a template designed to accelerate the creation of secure, scalable, and well-governed cloud environments using the Infrastructure as Code (IaC) philosophy with Terraform.
The MAIN GOAL is to provide a modular and reusable framework that serves as a foundation for deploying workloads across multiple clouds providers like AWS, Azure, GCP and OCI.

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🎯 Project Goals

• Modularity: Build independent and reusable modules for common cloud services (e.g., networking, identity, security).
• Environment Segregation: Utilize Terraform Workspaces to cleanly and securely isolate and manage configurations for different environments (DEV, QAS, PRD).
• Accelerator Template: Serve as a GitHub repository template, allowing new teams or projects to quickly start with best practices already built-in.
• Extensibility: Be the foundation for future integrations with Configuration Management tools like Ansible for application and OS provisioning.

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🏗️ Project Structure

The directory structure is designed to be intuitive and scalable. Each cloud provider has its own directory containing its respective modules.

enterprise-landing-zone/
├── .github/
│   └── workflows/          # (Optional) Future CI/CD workflows
├── modules/
│   ├── aws/
│   │   ├── network/        # Example: Module for network resources (VPC, Subnets)
│   │   │   ├── main.tf
│   │   │   ├── variables.tf
│   │   │   ├── outputs.tf
|   |   |   ├── locals.tf
│   │   │   └── environments/
│   │   │       └── dev.yaml  # Configuration for the DEV environment
│   │   │       └── qas.yaml  # Configuration for the QAS environment
│   │   │       └── main.yaml  # Configuration for the PRD environment
│   │   └── ... (other aws modules: iam, s3, eks, etc.)
│   ├── azure/
│   │   └── ... (modules for Azure)
│   ├── gcp/
│   │   └── ... (modules for GCP)
│   └── oci/
│       └── ... (modules for Oracle Cloud)
├── .gitignore
├── LICENSE
└── README.md

🔑 Key Concepts

• modules/: The root directory containing all reusable modules, organized by cloud provider.
• environments/: This directory holds the configuration-as-code for each environment in easy-to-read YAML files.
• locals.tf: This is the core of our dynamic configuration. It uses the built-in Terraform function yamldecode to read and parse the appropriate YAML file from the environments directory based on the name of the currently selected workspace. This automates configuration loading.

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🚀 Getting Started (Example with the aws/network module)

The configuration for each environment is now loaded automatically from a YAML file based on the selected Terraform workspace. The workflow is clean and simple.

Prerequisites:

• Terraform installed.
• AWS credentials configured in your environment.
• Git installed.

1. Clone this repository:

   git clone [https://github.com/vieira.devops/enterprise-landing-zone.git](https://github.com/vieira.devops/enterprise-landing-zone.git)
   cd enterprise-landing-zone/modules/aws/network

2. Initialize Terraform:

   terraform init

3. Select your Workspace: This is the crucial step. The workspace name must match the name of your config file (e.g., dev for dev-config.yaml).

   # Create the workspace if it doesn't exist
   terraform workspace new dev
   
   # Or select it if it already exists
   terraform workspace select dev

4. Plan and Apply: Notice that you no longer need the -var-file flag. Terraform will automatically load the configuration based on the workspace.

   # Plan the execution
   terraform plan
   
   # Apply the changes
   terraform apply

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🗺️ Future Roadmap

This project is constantly evolving. The next planned steps are:

• Add essential modules for AWS (IAM, S3, EKS).
• Develop the first modules for Azure and GCP (Network, Identity).
• Develop CI/CD pipeline examples for both GitHub Actions and Azure DevOps for automatic validation and deployment.
• Ansible Integration: Create playbooks to configure instances provisioned via Terraform.
• Add infrastructure tests with tools like Terratest.

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🤝 How to Contribute

Contributions are very welcome!

If you have ideas, suggestions, or find a bug, please open an Issue to discuss it. If you want to contribute code, please Fork the repository and submit a Pull Request.

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📄 License

This project is distributed under the MIT License. See the LICENSE file for more details.