Opella DevOps Technical Challenge

Reusable Terraform module for Azure Virtual Network + multi-environment deployment.

Architecture

• Reusable Module: modules/vnet/ (VNet + subnets + optional NSG)
• Environments:
  • Dev → eastus
  • Prod → westus (Microsoft paired region)
• Resources per environment:
  • Resource Group (with consistent tags)
  • Virtual Network + Subnets + NSG (via reusable module)
  • Windows Virtual Machine
  • Storage Account (Blob) + Private Endpoint
• Naming: Microsoft Cloud Adoption Framework (CAF) standards
• Tagging: Applied at Resource Group level (Environment, ManagedBy, Project, Region)

Clean Code & Quality Process

The following tools are automatically enforced in the CI pipeline:

• terraform fmt — code formatting validation
• tflint — linting and best practices
• trivy — security and misconfiguration scanning
• terraform-docs — auto-generated module documentation

CI/CD Pipelines

• Separate CI and CD pipelines (industry best practice)

  • terraform-ci.yml → Runs on every push:
    • Quality checks (fmt, tflint, trivy, terraform-docs)
    • Terraform Plan for both environments
    • Auto-generates and commits terraform-plan-dev.txt and terraform-plan-prod.txt
  • terraform-cd.yml → Manual deployment:
    • Apply to Dev
    • Apply to Prod (with manual approval gate)

• Both pipelines use Azure OIDC for secure authentication (no secrets stored in GitHub).

Deliverables

• terraform-plan-dev.txt (auto-updated by CI)
• terraform-plan-prod.txt (auto-updated by CI)
• CI Pipeline: .github/workflows/terraform-ci.yml
• CD Pipeline: .github/workflows/terraform-cd.yml

Module Documentation

See modules/vnet/README.md (auto-generated with terraform-docs).

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