Terraform Three Tier Infrasture on AWS

Demonstration of requirements understanding, proposing a solution and implementation of Infrastructure as a Code by using the latest tools and techniques.

---

• What is this repository for
• Problem Statement
• Proposed Solution
  • Deployment Flow
  • Infrastructure
• Assumptions
• Deliverable Content
  • Directory Structure
• Development Cycle
• Developer Setup
• Configuration
• Pre-reqs
• Deployments
• Contribute
• Screenshots

---

What is this repository for

• A terraform project to solve the task for tecAlliance
• Demonstrates infrastructure architecture for AWS Cloud
• CI/CD implementation using Github Actions in repo
• The live environment will be established on AWS.

---

Problem Statement:

Proposed Solution:

• As per the provided instructions, I would like to use terraform for the infrastructure provisioning.
• A custom VPC along with public and private subnests will be created.
• As demanded, a MySQL RDS Instance will be prepared for persistence.
• Backend EC2 will be hosted in one of the private subnets.
• The Frontend required multiple instances, so an Auto Scalling Group with the provided configs might be a good solution.
• For testing, a bastion host will be provisioned, which will have necessary access to lookup inside the private resources.
• Frontends will be connected to an Application Load Balancer.
• Frontend and Backend instances should include some script for bootstraping / initial configurations.
• Terraform should use necessary features for security and reusability of code.
• A ci/cd pipeline should be inplaced for mocking the whole flow in repository.
• Resources should be used as modules. (Will keep in same repo)
• The project should be prepared in a way to easily scale for a multi environment deployments with minimal changes.
• ALB endpoint should be shown as an output.

Deployment Flow

Infrastructure

Assumptions

• Frontends and Backend wont have any applications to serve the requests.
• Some health check servers will started i.e nginx,
• This task is to demonstrate the infrastructure best practices.
• There won't be a requirements to keep this system up for a long time, instead, some screenshot can be provided for validation.
• Provision of resources to setup a Bastion host will be conditional.
• Due to unavailability of SSL/TLS Certificate, ALB could not be tested on https port:443, but the code will be provided

Deliverable Content

Directory Structure

├── .github
│   └── workflows
│       └── terraform.yml
├── .gitignore
├── README.md
├── blueprint
│   ├── backend.tf
│   ├── main.tf
│   ├── modules
│   │   ├── backend
│   │   │   ├── main.tf
│   │   │   ├── outputs.tf
│   │   │   └── variables.tf
│   │   ├── bastion
│   │   │   ├── main.tf
│   │   │   ├── outputs.tf
│   │   │   └── variables.tf
│   │   ├── database
│   │   │   ├── main.tf
│   │   │   ├── outputs.tf
│   │   │   └── variables.tf
│   │   ├── frontend
│   │   │   ├── main.tf
│   │   │   └── variables.tf
│   │   ├── load_balancer
│   │   │   ├── main.tf
│   │   │   ├── outputs.tf
│   │   │   └── variables.tf
│   │   ├── network
│   │   │   ├── main.tf
│   │   │   ├── outputs.tf
│   │   │   └── variables.tf
│   │   └── security_groups
│   │       ├── main.tf
│   │       ├── outputs.tf
│   │       └── variables.tf
│   ├── outputs.tf
│   └── variables.tf
├── envs
│   └── dev
│       ├── main.tf
│       ├── outputs.tf
│       └── variables.tf
└── scripts
    ├── init_backend_server.sh
    ├── init_bastion_host.sh
    └── init_frontend_server.sh

Development Cycle

• Distributes the whole development into Small tasks
• Each Issue shows a feature
• Each commit shows a small progress
• Pull Requests are done for major tasks
• Pipelines Each commit is built by CI/CD Pipeline

Developer Setup

To setup the project locally you need to clone this repo, from main branch or some latest TAG

cd to envs/dev

# cd to `envs/dev` and initialize the project
$ terraform init

#  to Validate
$ terraform validate

# to plan
$ terraform plan

# Apply the changes to aws cloud
$ terraform apply

# Cleanup
$ terraform destroy

Configuration

• Terraform should be installed
• ⚠️ AWS Credentials should be setup as defualt profile of local machine

Pre-reqs

• terrafom (used Terraform v1.4.3-dev)
• aws credentials
• VS Code

Deployment

• When a pull request is merged in main, Github Action starts and following steps are done by automated CI/CD:
  • Makes a deployment to AWS (Mock)

Contribution guidelines

• Forks are always appreciated

Screenshots

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---

• 

  ---