Kubernetes Build (local development)

For running locally, install https://microk8s.io/docs/. Otherwise, use a kubernetes provider (Google Cloud, OpenShift etc)

1. Start microk8s, enable addons, and deploy

# Start your local microk8s environment (you might prefer to use minikube)
microk8s.start
microk8s.enable dns dashboard registry #Only needed once
microk8s.status

Without kafka

# Deploy open bank project
kubectl kustomize base/ | kubectl apply -f - #pipe from stdin
# Output: 
service/obpapi-service created
deployment.apps/obp-deployment created
service/postgres-service created
deployment.apps/obp-postgres created
persistentvolumeclaim/postgres created

With kafka

# Zookeeper
kubectl apply -f zookeeper-no-anti-afinity-no-fault-tolerance.yaml
# Kafka 
kubectl apply -f kafka-no-anti-affinity.yaml
# Open bank project
kubectl apply -f obpapi_k8s_with_kafka.yaml
# Output:
service/zk-svc created
configmap/zk-cm created
statefulset.apps/zk created
service/kafka-svc created
poddisruptionbudget.policy/kafka-pdb created
statefulset.apps/kafka created
secret/postgres-credentials created
secret/obp-credentials configured
persistentvolumeclaim/postgres-volume-claim created
service/obpapi-service created
deployment.apps/obp-deployment created
service/postgres-service created
deployment.apps/postgres created

Scale the OBPAPI deployment

Currently only the obp-deployment can be scaled. The Postgres instance cannot until we implement Patroni, or use a managed service like RDS(AWS) or Cloud SQL (Google)

WARNING: If your cluster is too small and/or autoscaling is disabled, your cluster is the limit!

Steps to scale to more obpapi instances:

kubectl scale deployment.v1.apps/obp-deployment --replicas=5
# Monitor progress of scale up
kubectl rollout status deployment.v1.apps/obp-deployment
kubectl describe deployment obp-deployment

DNS Mapping hostname to cluster (Poor mans ingress)

HTTP (Done)

The service obpapi-service type is LoadBalancer, which means an external load balancer is provisioned (depending on the cloud provider being used). We get a public ipv4 address, and can use this to point a DNS A record to the ip.

# Find exernal ip
kubectl get services
# Copy 'external ip'

Traffic from the external load balancer will be directed at the backend Pods. HTTP: https://cloud.google.com/kubernetes-engine/docs/tutorials/http-balancer

HTTPS (TODO)

HTTPS requires different steps: https://cloud.google.com/load-balancing/docs/https/

Google Cloud Example

The following creates a three node cluster on Google Cloud with autoscaling enabled. Warning it enabled preemptible nodes, which mean they could get shutdown at anytime, and always within 24 hours. Why use these? They're much cheaper, and if architected correctly failure of a node should not impact the system. Remember a borg master is replicated 5 times, and the kubernetes master is abstracted away (and not charged for) on Google's Kubernetes so it's always available.

1. Create a cluster of nodes

The first time you do this, you will hit quota errors, such as max ip addresses per account. You must request a change to your quota to allow this. Change 'projectname' to your project name.

gcloud beta container \
    --project "<projectname>" \
    clusters create "standard-cluster-1" \
    --zone "europe-north1-a" \
    --username "admin" \
    --cluster-version "1.11.6-gke.2" \
    --machine-type "f1-micro" \
    --image-type "COS" \
    --disk-type "pd-standard" \
    --disk-size "30" \
    --metadata disable-legacy-endpoints=true \
    --scopes "https://www.googleapis.com/auth/devstorage.read_only","https://www.googleapis.com/auth/logging.write","https://www.googleapis.com/auth/monitoring","https://www.googleapis.com/auth/servicecontrol","https://www.googleapis.com/auth/service.management.readonly","https://www.googleapis.com/auth/trace.append" \
    --preemptible \
    --num-nodes "3" \ 
    --enable-cloud-logging \
    --enable-cloud-monitoring \ 
    --enable-ip-alias \
    --network "projects/<projectname>/global/networks/default" \
    --subnetwork "projects/projectname/regions/europe-north1/subnetworks/default" \ 
    --default-max-pods-per-node "110" \ 
    --enable-autoscaling \
    --min-nodes "3" \
    --max-nodes "10" \
    --addons HorizontalPodAutoscaling,HttpLoadBalancing,KubernetesDashboard \
    --enable-autoupgrade \
    --enable-autorepair \
    --enable-autoprovisioning \
    --min-cpu 1 --max-cpu 1 \
    --min-memory 1 --max-memory 1 \

2. Connect to your cluser

From your terminal, connect to your cluser. You can also do this through the Google 'web console' interface if you prefer.

gcloud container clusters get-credentials <cluster-name> --zone europe-north1-a --project <project-name>

3. Deploy OBPAPI to Google Kubernetes

Deploy the manifests to your cluster. Kubernetes will read this and deploy the objects within the document.

kubectl kustomize base/ | kubectl apply -f - #pipe from stdin

Useful commands to see progress:

kubectl get pods
kubectl logs -f <pod-name>

4. Patching the reclaim policy to Retain

https://kubernetes.io/docs/tasks/administer-cluster/change-pv-reclaim-policy/

kubectl get pv
kubectl patch pv <your-pv-name> -p '{"spec":{"persistentVolumeReclaimPolicy":"Retain"}}'

5. Access the Dashboard

If you like, you can view the pretty dashboard showing the deployment load, progess etc:

kubectl create clusterrolebinding kubernetes-dashboard --clusterrole=cluster-admin --serviceaccount=kube-system:kubernetes-dashboard

kubectl proxy

You can now view the dashboard at: http://localhost:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/overview?namespace=default

---

SSL Termination

How do we route http traffic to obp?

We use cert manager.

# GKE (Google Kubernetes Engine) only
kubectl create clusterrolebinding cluster-admin-binding \
  --clusterrole=cluster-admin \
  --user=$(gcloud config get-value core/account)
# Create a namespace to run cert-manager in
kubectl create namespace cert-manager
# Disable resource validation on the cert-manager namespace
kubectl label namespace cert-manager certmanager.k8s.io/disable-validation=true
# Install the CustomResourceDefinition resources
kubectl apply -f https://raw.githubusercontent.com/jetstack/cert-manager/release-0.6/deploy/manifests/00-crds.yaml

Docker only Build

If you just want run Open Bank project locally on your machine quickly, you can use this docker image rather than pulling from docker hub (e.g. you're offline).

See BuildWarDockerfile # Build it docker build --no-cache --tag obpapi -f BuildWarDockerfile # Or pull and run it docker run -p 8080:8080 chrisjsimpson/obp:minimal

If you already have a war file, just inject it into the build:

```
docker build --no-cache -t obpapi-kube .
docker run --env DB_USER=username --env DB_PASS=password --env DB_NAME=dbname --env DB_HOST=127.0.0.1 --network="host" -p8080:8080 obpapi-kube
```

Run

docker run -p 8080:8080 obpapi

Visit http://127.0.0.1:8080/

See also

• https://docs.docker.com/develop/develop-images/multistage-build/
• https://www.eclipse.org/jetty/documentation/9.4.x/maven-and-jetty.html

Minikube notes

To view OBP interface locally, you must use the command: minikube service obpapi-service which will map ports and open a web browser pointing to the obp service.

Additionally, you may need to change the obpapi-service type to from LoadBalancer to NodePort, since on your local machine you may not have a default loadbalancer defined on your kubernetes instance