Shashwat-05/CanaryDeployK8S

DOCUMENTATION

kubectl steps as follows

1. Start minikube single node cluster without checking virtualization technology.
   minikube start --driver=virtualbox --no-vtx-check

2. Install ingress controller, so that later ingress resource can function.
   minikube addons enable ingress - it's better to user minikube's ingress controller, but nginx ingress controller can be installed from helm or manifests itself with some modifications required.

Alternative step - install nginx-ig-controller with helm

    # helm repo add nginx-stable https://helm.nginx.com/stable   
    # helm repo update  
    # helm install nginx-ingress nginx-stable/nginx-ingress

then,
kubectl edit svc/nginx-ingress-svc - add this below clusterIPs block

    externalIPs:
    - <minikube_ip>

reason - as this svc is loadbalancer type and there won't be any externalIP
in a local minikube, therefore providing one manually.

3. Deploy both blue-app & green-app with their services.
   kubectl apply -f blue-app-deployment.yaml -f green-app-deploy.yaml

4. Provision 2 nginx-ingress, Ist one forwards traffic to the blue-app normally but 2nd one follows canary strategy and will forword only 25% traffic to green-app and rest will be forward to blue-app via Ist ingress i.e, remaining 75%.
   kubectl apply -f nginx-ingress-controller.yaml

Note - if requirement is to split traffic btw more than 2 apps - use nginx VirtualServer resource instead kubectl apply -f nginx-vserver-lb.yaml

5. get minikube ip - minikube ip

6. curl down the deployed apps 10 times (linix command).
   for i in {1..10}; do curl http://<minikube_ip> ; done

7. registering hostname.
   echo 'minikube_ip facets.app' and now for i in {1..10}; do curl http://facets.app ; done

terraform steps to follow

1. terraform init

2. terraform apply - install helm chart separately first, (either comment out all other resource files and run apply twice, (i) after commenting, (ii) after uncommenting)
   as nginx-ingress-controller chart needs to be deployed first else tf will throw erros as virtualserver CRD wont be existing.
   this will do

• deploy all three apps from app.json
• create services for each
• create traffic split with nginx virtualserver
• create ingress-controller,crds,etc with helm.

(provide the minikube_ip manually as external ip to the ingress-controller service)