Kubor - Kubernetes Overseer

Kubor is a tool to view and analyze resource usage metrics of Kubernetes cluster. It groups usage metrics on namespace level and calculates hourly usage averages from total resources available. It abstracts cluster resources into four core metrics (cpu, memory, network and storage) for which monthly costs can be set. This can be used to help generating invoices in multi-tenant environments.

Overview

Application consists of following components:

• Frontend (React) that displays cluster usage metrics and costs.
• Backend (Node.js) that serves static frontend assets, provides REST API for frontend, acts as a reverse proxy for Prometheus and handles metrics collection.
• Database (SQLite) that stores cluster cost data and usage metrics.

Requirements

• Prometheus for resource usage metrics
• Configured Persistent Volume for database

Local development

Kubor requires access to Prometheus to get resource usage metrics. For local development a simple port forward to Prometheus is sufficient. Another option is to deploy the application container to (local minikube) cluster and then interact with it using tools like Telepresence.

Requirements

• kubectl
• Minikube

Without container registry

Run frontend in development mode

cd client
yarn run start:local

Run backend that provides REST API for frontend, acts as reverse proxy for Protmetheus and collects cluster metrics.

cd server
yarn run start:local

Finally proxy traffic to Prometheus using kubectl.

kubectl -n monitoring port-forward prometheus-k8s-0 9090

Backend will automatically initialize database and run migrations. You can seed cluster cost data by issuing following command in server directory

./node_modules/knex/bin/cli.js seed:run

With private container registry using Minikube

For this, we'll be using local container registry inside Kubernetes. I will follow steps mentioned in this great blog post that covers setting up the container registry. We also need to start minikube with insecure registry flag to enable insecure communication between the docker engine and registries.

minikube start --insecure-regisry localhost:5000

Deploy container registry.

kubectl apply -f deploy/local-registry.yml

Access Docker daemon inside minikube

eval $(minikube docker-env)

Build Docker image.

./build.sh

Tag it and push it to our registry

docker tag kubor:<version> localhost:5000/kubor:<version>
docker push localhost:5000/kubor:<version>

Edit following lines in file deploy/kubor.yaml:

• 45: image to match the image version
• 53: value of PROMETHEUS_URL to match your Prometheus deployment

and finally deploy to Kubernetes cluster

kubectl apply -f deploy/kubor.yaml

Get URL to access the app

minikube service kubor --url

Build image

Build Docker image including server and static assets

./build.sh

Deploy to Kubernetes

Edit image and PROMETHEUS_URL in kubernetes/kubor.yaml accordingly and then

kubectl apply -f kubernetes/kubor.yaml