This repository contains the necessary Kubernetes configurations to set up and manage the DHIS2 application with a CNPG PostGIS database within a Kubernetes cluster. Below are the components and their respective purposes within our infrastructure.
Manages TLS certificates to ensure secure communication within the cluster and for inbound traffic.
Houses the configurations for Containerized PostgreSQL with PostGIS, providing spatial database capabilities for DHIS2.
Manages Google Cloud Platform (GCP) resources via Kubernetes configurations.
Operates the Config Connector to keep GCP resources and Kubernetes configurations in sync.
Contains deployment configurations for the DHIS2 application, designed to connect with the PostGIS database.
Utilizes Flux to implement GitOps, automatically applying changes from a Git repository to the cluster.
Configures Istio as an Ingress controller to manage external access to services in the cluster.
Flux is used to keep our Kubernetes cluster state synchronized with the configuration defined in our git repository. The sync.yaml file is a key part of this setup.
The sync.yaml file contains the Flux GitRepository and Kustomization resources, defining where Flux should look for the configuration files and how they should be applied to the cluster.
To apply the sync.yaml file and enable Flux syncing:
kubectl apply -f path/to/sync.yaml
### Deployment Process
1. **DHIS2 Kubernetes Deployment**: We deploy DHIS2 as a set of replicated pods within the Kubernetes cluster to ensure high availability. The deployment configuration specifies the DHIS2 Docker image and sets the necessary environment variables for database connectivity.
- **Database Connectivity**: Environment variables `DB_USERNAME` and `DB_PASSWORD` are set through Kubernetes secrets to maintain security. These credentials are used by DHIS2 to connect to the CNPG PostGIS database.
2. **CNPG Database Setup**: The CNPG system provides a PostgreSQL database with the PostGIS extension. It includes its own set of Kubernetes objects like Deployments, Services, and PersistentVolumeClaims to ensure data persistence.
- **Integration with DHIS2**: DHIS2 connects to the CNPG database using a JDBC URL specified in the environment variables or a configuration file. This URL includes the service name of the CNPG database as the hostname, which Kubernetes resolves internally.
3. **ConfigMaps and Secrets**: Configuration Maps (ConfigMaps) and Secrets store configuration data and sensitive information respectively. They are mounted into DHIS2 pods as environment variables or files.
- **ConfigMaps**: May include configurations like system settings or overrides.
- **Secrets**: Store sensitive information like database credentials, used by both DHIS2 and CNPG deployments.
# cnpg-system
The `cnpg-system` directory contains the necessary configurations for deploying a containerized PostgreSQL database with the PostGIS extension, which enables spatial and geographic data support. This setup is tailored for Kubernetes environments, allowing for scalable and managed database services.
## Prerequisites
Before deploying the CNPG system, the following prerequisites must be met:
- A Kubernetes cluster set up and accessible.
- PersistentVolumes (PV) provisioned or a dynamic storage provisioner configured.
- Necessary RBAC roles and RoleBindings set up for resource access within the cluster.
## Deployment
The deployment process involves several Kubernetes manifests that set up the CNPG system:
- **PersistentVolumeClaims (PVCs)**: For data storage and persistence.
- **Deployments**: To run the PostgreSQL with PostGIS containers.
- **Services**: To expose the database within the cluster.