feat: Add Terraform infrastructure as code

.gitignore

@@ -21,3 +21,10 @@ coverage/
 # Logs
 *.log
 logs/
+
+# Terraform
+**/.terraform/*
+*.tfstate
+*.tfstate.*
+*.tfvars
+.terraform.lock.hcl

terraform/README.md

@@ -0,0 +1,221 @@
+# Terraform Infrastructure as Code
+
+This directory contains Terraform configurations for deploying the Quote App to different environments.
+
+## Structure
+
+```
+terraform/
+├── modules/
+│   ├── docker/          # Docker module (containers, images, networks)
+│   └── kubernetes/      # Kubernetes module (pods, services, HPA)
+├── environments/
+│   ├── dev/            # Development environment (Docker)
+│   └── prod/           # Production environment (Kubernetes)
+└── main.tf             # Root configuration
+```
+
+## Prerequisites
+
+- Terraform >= 1.0
+- Docker (for dev environment)
+- kubectl and Minikube (for prod environment)
+
+## Usage
+
+### Development Environment (Docker)
+
+```bash
+cd environments/dev
+
+# Initialize Terraform
+terraform init
+
+# Preview changes
+terraform plan
+
+# Apply configuration
+terraform apply
+
+# Access application
+curl http://localhost:3000/health
+
+# Destroy resources
+terraform destroy
+```
+
+### Production Environment (Kubernetes)
+
+```bash
+cd environments/prod
+
+# Ensure Minikube is running
+minikube status
+
+# Initialize Terraform
+terraform init
+
+# Preview changes
+terraform plan
+
+# Apply configuration
+terraform apply
+
+# Check deployment
+kubectl get all -n quote-app
+
+# Access application
+minikube service quote-app-service -n quote-app --url
+
+# Destroy resources
+terraform destroy
+```
+
+## Modules
+
+### Docker Module
+
+Manages Docker resources:
+- Docker images
+- Docker containers
+- Docker networks
+- Health checks
+
+**Variables:**
+- `image_name` - Docker image name
+- `image_tag` - Image tag (default: latest)
+- `container_name` - Container name
+- `internal_port` - Container port (default: 3000)
+- `external_port` - Host port (default: 3000)
+- `environment_vars` - Environment variables (map)
+- `restart_policy` - Restart policy (default: unless-stopped)
+
+**Outputs:**
+- `container_id` - Container ID
+- `container_name` - Container name
+- `network_name` - Network name
+- `access_url` - Application URL
+
+### Kubernetes Module
+
+Manages Kubernetes resources:
+- Namespace
+- ConfigMap
+- Deployment
+- Service (NodePort)
+- Horizontal Pod Autoscaler
+
+**Variables:**
+- `namespace` - Kubernetes namespace
+- `app_name` - Application name
+- `image` - Docker image
+- `replicas` - Number of replicas (default: 3)
+- `container_port` - Container port (default: 3000)
+- `service_port` - Service port (default: 80)
+- `node_port` - NodePort (default: 30080)
+- `environment_vars` - Environment variables (map)
+- `cpu_request` - CPU request (default: 100m)
+- `cpu_limit` - CPU limit (default: 500m)
+- `memory_request` - Memory request (default: 128Mi)
+- `memory_limit` - Memory limit (default: 256Mi)
+- `hpa_enabled` - Enable HPA (default: true)
+- `hpa_min_replicas` - Min replicas (default: 2)
+- `hpa_max_replicas` - Max replicas (default: 10)
+- `hpa_cpu_threshold` - CPU threshold % (default: 70)
+
+**Outputs:**
+- `namespace` - Namespace name
+- `deployment_name` - Deployment name
+- `service_name` - Service name
+- `service_port` - Service port
+- `node_port` - NodePort
+
+## Common Commands
+
+```bash
+# Initialize
+terraform init
+
+# Format code
+terraform fmt -recursive
+
+# Validate configuration
+terraform validate
+
+# Plan changes
+terraform plan
+
+# Apply changes
+terraform apply
+
+# Show current state
+terraform show
+
+# List resources
+terraform state list
+
+# Show outputs
+terraform output
+
+# Destroy resources
+terraform destroy
+```
+
+## State Management
+
+Terraform stores state in `terraform.tfstate` file. This file contains:
+- Current infrastructure state
+- Resource dependencies
+- Metadata
+
+**Important:**
+- Never edit state files manually
+- Keep state files secure (contain sensitive data)
+- For production, use remote state (S3, Terraform Cloud)
+
+## Best Practices
+
+1. **Use modules** for reusable configurations
+2. **Separate environments** (dev, staging, prod)
+3. **Use variables** for configurable values
+4. **Output important values** for easy access
+5. **Version control** all Terraform files
+6. **Use remote state** for production
+7. **Plan before apply** to review changes
+8. **Use workspaces** for environment isolation
+
+## Troubleshooting
+
+### Issue: Provider authentication failed
+
+```bash
+# For Docker
+docker ps  # Verify Docker is running
+
+# For Kubernetes
+kubectl cluster-info  # Verify cluster access
+```
+
+### Issue: Resource already exists
+
+```bash
+# Import existing resource
+terraform import module.quote_app_k8s.kubernetes_namespace.app quote-app
+
+# Or destroy and recreate
+terraform destroy
+terraform apply
+```
+
+### Issue: State lock
+
+```bash
+# Force unlock (use with caution)
+terraform force-unlock <lock-id>
+```
+
+## Additional Resources
+
+- [Terraform Documentation](https://www.terraform.io/docs)
+- [Docker Provider](https://registry.terraform.io/providers/kreuzwerker/docker/latest/docs)
+- [Kubernetes Provider](https://registry.terraform.io/providers/hashicorp/kubernetes/latest/docs)

terraform/environments/dev/main.tf

@@ -0,0 +1,49 @@
+terraform {
+  required_version = ">= 1.0"
+
+  required_providers {
+    docker = {
+      source  = "kreuzwerker/docker"
+      version = "~> 3.0"
+    }
+  }
+}
+
+provider "docker" {
+  host = "unix:///var/run/docker.sock"
+}
+
+module "quote_app_docker" {
+  source = "../../modules/docker"
+
+  image_name     = "adityajareda/quote-app"
+  image_tag      = "latest"
+  container_name = "quote-app-dev"
+  internal_port  = 3000
+  external_port  = 3000
+
+  environment_vars = {
+    NODE_ENV    = "development"
+    PORT        = "3000"
+    APP_NAME    = "Quote App"
+    APP_VERSION = "1.0.0"
+    LOG_LEVEL   = "debug"
+  }
+
+  restart_policy = "unless-stopped"
+}
+
+output "container_id" {
+  description = "Docker container ID"
+  value       = module.quote_app_docker.container_id
+}
+
+output "access_url" {
+  description = "Application access URL"
+  value       = module.quote_app_docker.access_url
+}
+
+output "container_name" {
+  description = "Container name"
+  value       = module.quote_app_docker.container_name
+}

terraform/environments/dev/variables.tf

@@ -0,0 +1,5 @@
+variable "docker_host" {
+	description = "Docker daemon host"
+	type = string
+	default = "unix:///var/run/docker.sock"
+}

terraform/environments/prod/main.tf

@@ -0,0 +1,64 @@
+terraform {
+  required_version = ">= 1.0"
+
+  required_providers {
+    kubernetes = {
+      source  = "hashicorp/kubernetes"
+      version = "~> 2.24"
+    }
+  }
+}
+
+provider "kubernetes" {
+  config_path = "~/.kube/config"
+}
+
+module "quote_app_k8s" {
+  source = "../../modules/kubernetes"
+
+  namespace      = "quote-app"
+  app_name       = "quote-app"
+  image          = "adityajareda/quote-app:latest"
+  replicas       = 3
+  container_port = 3000
+  service_port   = 80
+  node_port      = 30080
+
+  environment_vars = {
+    NODE_ENV    = "production"
+    PORT        = "3000"
+    APP_NAME    = "Quote App"
+    APP_VERSION = "1.0.0"
+    LOG_LEVEL   = "info"
+  }
+
+  cpu_request    = "100m"
+  cpu_limit      = "500m"
+  memory_request = "128Mi"
+  memory_limit   = "256Mi"
+
+  hpa_enabled       = true
+  hpa_min_replicas  = 2
+  hpa_max_replicas  = 10
+  hpa_cpu_threshold = 70
+}
+
+output "namespace" {
+  description = "Kubernetes namespace"
+  value       = module.quote_app_k8s.namespace
+}
+
+output "deployment_name" {
+  description = "Deployment name"
+  value       = module.quote_app_k8s.deployment_name
+}
+
+output "service_name" {
+  description = "Service name"
+  value       = module.quote_app_k8s.service_name
+}
+
+output "access_port" {
+  description = "NodePort for external access"
+  value       = module.quote_app_k8s.node_port
+}

terraform/environments/prod/variables.tf

@@ -0,0 +1,5 @@
+variable "kubeconfig_path" {
+	description = "Path to kubeconfig file"
+	type = string
+	default = "~/.kube/config"
+}

terraform/main.tf

@@ -0,0 +1,31 @@
+# ============================================
+# ROOT TERRAFORM CONFIGURATION
+# ============================================
+# This is the main entry point for Terraform
+
+terraform {
+  required_version = ">= 1.0"
+}
+
+# ============================================
+# INSTRUCTIONS
+# ============================================
+# 
+# To use this Terraform configuration:
+#
+# 1. For Development (Docker):
+#    cd environments/dev
+#    terraform init
+#    terraform plan
+#    terraform apply
+#
+# 2. For Production (Kubernetes):
+#    cd environments/prod
+#    terraform init
+#    terraform plan
+#    terraform apply
+#
+# 3. To destroy:
+#    terraform destroy
+#
+# ============================================