Repositories

The VOL infrastructure is divided into two repositories: vol-app and vol-terraform.

The rationale for this split is explained in RFC-005. At a high level, this approach was the only identified feasible option for implementing the migration the VOL application to ECS and establishing CI/CD workflows.

danger

The vol-app repository depends on the vol-terraform repository. This relationship must remain unidirectional to prevent circular dependencies. Circular dependencies can disrupt disaster recovery processes and complicate infrastructure re-creation.

Controlling Traffic Flow

ECS-related resources created by vol-app were intentionally designed to coexist with the existing EC2 infrastructure provisioned by the vol-terraform repository. This approach ensures a smooth transition to the new infrastructure. Traffic flow can be managed by setting a listener rule with a higher priority (0 being the highest priority).

tip

The listener rule is controlled by the variable: service.listener_rule_enable variable.

To push traffic to the ECS service, set service.listener_rule_enable = true. This can be controlled per environment and service.

# vol-app/infra/terraform/environments/[env]/main.tf

module "service" {
  source = "../../modules/service"

  # ...

  services = {
    "service" = {
      # ...

      listener_rule_enable = true # default is `true`.
    }
  }
}