Terraform Infrastructure Improvements - Issues #704, #705, #706, #707

Overview

Comprehensive infrastructure-as-code improvements for PredictIQ Terraform configuration, addressing remote state management, resource tagging, input validation, and environment separation.

Changes Implemented

Issue #704: Configure S3 Backend with DynamoDB State Locking

• Created bootstrap.sh script to initialize S3 bucket and DynamoDB table for remote state
• Added backend-config.hcl for flexible backend configuration management
• Updated main.tf to use dynamic backend configuration via -backend-config flag
• Enabled S3 versioning, encryption (AES256), and public access blocking
• Enabled DynamoDB point-in-time recovery for state locking
• Documented bootstrap process in infrastructure/README.md

Issue #705: Enforce Resource Tagging Strategy

• Created locals.tf with standardized common tags: Project, Environment, Owner, ManagedBy
• Updated all 5 modules (vpc, rds, redis, ecs, monitoring) to enforce consistent tagging
• Applied common tags to all AWS resources using merge() function
• Enables cost allocation, resource ownership tracking, and compliance reporting

Issue #706: Add Validation Blocks to variables.tf

• Added 16 comprehensive validation blocks for critical variables:
  • aws_region: Valid AWS region format validation
  • vpc_cidr_block: Valid CIDR notation validation
  • db_name: Lowercase alphanumeric, max 63 characters
  • db_username: 1-16 character length validation
  • db_password: Minimum 8 character requirement
  • db_instance_class: Valid RDS instance type validation
  • allocated_storage: 20-65536 GB range validation
  • backup_retention_days: 1-35 day range validation
  • redis_node_type: Valid ElastiCache node type validation
  • redis_num_nodes: 1-500 node range validation
  • redis_engine_version: X.Y format validation
  • api_image_uri: Valid ECR image URI format validation
  • api_container_port: 1024-65535 port range validation
  • api_desired_count: 1-10 task count validation
  • api_cpu: Valid Fargate CPU values (256, 512, 1024, 2048, 4096)
  • api_memory: Valid Fargate memory values
• All validations include descriptive error messages for troubleshooting

Issue #707: Separate Staging and Production Environments

• Reorganized environments/ directory structure:
  • dev.tfvars for development (local state)
  • staging/terraform.tfvars + staging/backend.hcl (separate S3 bucket & DynamoDB table)
  • production/terraform.tfvars + production/backend.hcl (separate S3 bucket & DynamoDB table)
• Each environment has isolated state files preventing accidental cross-environment modifications
• Created comprehensive environments/README.md with:
  • Deployment instructions for each environment
  • CI/CD approval workflow for production deployments
  • State file locations and disaster recovery procedures
  • Best practices for environment management
• Updated main infrastructure/README.md with new directory structure

Files Modified

• infrastructure/terraform/main.tf - Dynamic backend configuration
• infrastructure/terraform/variables.tf - Added 16 validation blocks
• infrastructure/terraform/locals.tf - New common tags definition
• infrastructure/terraform/bootstrap.sh - New bootstrap script
• infrastructure/terraform/backend-config.hcl - New backend configuration
• infrastructure/terraform/modules/vpc/main.tf - Enforce tagging
• infrastructure/terraform/modules/rds/main.tf - Enforce tagging
• infrastructure/terraform/modules/redis/main.tf - Enforce tagging
• infrastructure/terraform/modules/ecs/main.tf - Enforce tagging
• infrastructure/terraform/modules/monitoring/main.tf - Enforce tagging
• infrastructure/terraform/environments/README.md - New environment documentation
• infrastructure/terraform/environments/staging/ - New staging environment config
• infrastructure/terraform/environments/production/ - New production environment config
• infrastructure/README.md - Updated with new structure

Testing

• terraform validate passes with all validation blocks
• Backend configuration tested with -backend-config flag
• All modules apply successfully with new tagging strategy
• Environment separation verified with distinct state files

Benefits

✅ Remote state management with team collaboration support
✅ Consistent resource tagging for cost allocation and compliance
✅ Input validation prevents invalid configurations at plan time
✅ Environment isolation prevents accidental production changes
✅ Comprehensive documentation for infrastructure management

Closes #704
Closes #705
Closes #706
Closes #707