Overview

CNOnt-Broker is a system which provides connection between cloud native ontology
and Kubernetes cluster. Using Web Ontology Language (OWL) language.
Application expose web API which is used by a client application.

How to run

git clone https://github.com/greg9702/CNOnt-Broker.git
cd CNOnt-Broker
docker-compose up --build

If you would like to run server directly on your machine run:

export GO111MODULE=on
cd core
go run main.go --kubeconfig <PATH_TO_KUBE_CONFIG> --logLevel <LOGLEVEL>

Make sure to set GO111MODULE to on. Without this issues with dependencies can occur.

Cluster setup

Install kind - tool for running local Kubernetes clusters using Docker container "nodes".
If you have go (1.11+) and docker installed:

GO111MODULE="on" go get sigs.k8s.io/kind@v0.8.1

If you would like to have access to kind from your console run:

kubectl config use-context kind-<cluster name>

Set up cluster by running:

cd cluster
./setup.sh

You are ready to go!

File cluster-config.yaml contains configuration for cluster. Visit link for more details.

Script by default creates admin account, which access token can be obtained by running script getadmintoken.sh in cluster directory.

Kuberentes client API documentation

Documentation can be found here.

Issues

According to kubernetes/kubeadm#1292, there can occur bug where corde-dns remains in CrashLoopBackOff state.
To fix this:

kubectl -n kube-system edit configmap coredns

Remove or comment out the line with loop, save and exit.

kubectl -n kube-system delete pod -l k8s-app=kube-dns

System functionality and architecture

System is able to create deployment based on the ontology file.

Every system element runs in its own docker container.
There are three of them:

core - Web API server
cluster - Kubernetes cluster
client - client application created in React

Kubernetes cluster creates proxy on port 8001 and can be accessed from other containers and host machine. Client application exposes port 3000 on localhost. Server application exposes port 8080.

Deployment is created based on file core/ontology/asssets/CNOnt.owl which is OWL file with functional syntax. If file is incorrect in some way, deployment won't be created and API would return error code and message.

Server exposes three enpoints:

api/v1/create-deployment - creates deployment
api/v1/delete-deployment - delete deployment if exists
api/v1/preview-deployment - returns preview of deployment
/api/v1/serialize-cluster-conf - create a cluster mapping based on used ontology template file