Infrastructure-as-Code ChatApp Deployment

Terraform setup for deploying a real-time chat app on AWS. Handles networking, compute, DNS, and monitoring.

Project Overview

Everything needed to spin up the chat app on AWS is defined in Terraform. Network, compute, security groups, and DNS are all version-controlled and repeatable.

Key Features

• Automated Infrastructure Provisioning: Complete AWS infrastructure setup with Terraform
• Scalable Architecture: EC2 instances with auto-scaling capabilities
• DNS Management: Custom domain routing and SSL certificate management
• Security Best Practices: VPC setup, security groups, and IAM role configuration
• Environment Management: Separate configurations for development, staging, and production
• Monitoring Setup: CloudWatch integration for application and infrastructure monitoring

Infrastructure Components

graph TD
    User([Users]) --> |HTTPS| Route53[Route 53 DNS]
    Route53 --> ALB[Application Load Balancer]
    
    subgraph "AWS Cloud (VPC)"
        ALB --> ASG[Auto Scaling Group]
        
        subgraph "Compute"
            ASG --> EC2_1[EC2 Node 1]
            ASG --> EC2_2[EC2 Node 2]
        end
    end
    
    terraform((Terraform)) -.-> |Provisions| Route53
    terraform -.-> |Provisions| ALB
    terraform -.-> |Provisions| ASG

Network Layer

• VPC Configuration: Custom Virtual Private Cloud with public and private subnets
• Security Groups: Firewall rules for web traffic and SSH access
• Internet Gateway: Public internet access configuration
• Route Tables: Network routing for optimal traffic flow

Compute Layer

• EC2 Instances: Optimized instance types for chat application workload
• Auto Scaling Groups: Automatic scaling based on traffic demand
• Load Balancer: Application Load Balancer for high availability
• Key Pair Management: SSH key management for secure access

DNS and SSL

• Route 53: DNS management and domain routing
• Certificate Manager: SSL/TLS certificate provisioning
• CloudFront: CDN setup for improved performance

Technology Stack

• Infrastructure as Code: Terraform with HCL syntax
• Cloud Provider: AWS (EC2, VPC, Route 53, CloudWatch)
• Configuration Management: Terraform modules and variables
• Version Control: Git-based infrastructure versioning
• CI/CD Integration: GitHub Actions for automated deployments

DevOps Practices

• Infrastructure Versioning: Git-based infrastructure change tracking
• Environment Parity: Consistent infrastructure across all environments
• Automated Deployments: One-click infrastructure provisioning
• Resource Tagging: Organization and cost tracking for all resources
• State Management: Remote state storage with locking mechanism

Architecture Decisions

• Why Terraform over CloudFormation: Provider-agnostic syntax kept the door open for multi-cloud, and the module ecosystem meant battle-tested patterns for VPC/ALB/ASG were available rather than hand-rolling each resource.
• Why EC2 + ASG over Fargate/EKS: For a chat app at this scale, container orchestration overhead wasn’t justified — EC2 with an Auto Scaling Group gave horizontal scale without the control-plane cost of Kubernetes.
• Public/private subnet split: Application instances live in private subnets; only the ALB sits public-facing. Removes the SSH attack surface and forces traffic through one observable choke point.
• Remote state with locking: S3 backend + DynamoDB lock table prevents concurrent terraform apply from corrupting state — important once more than one engineer touches the repo.

Trade-offs

• ASG-based scaling is slower to react than serverless cold starts but predictably cheaper at sustained load — the right call for a long-lived socket workload.
• All-in on AWS means provider lock-in; Terraform’s syntax mitigates this but the resource graph itself is AWS-shaped.
• CloudFront was specced but only adds value once static assets dominate egress — left as an opt-in module rather than a default.