This is a simple demo project to demonstrate knative-serving. If you want to follow this demo, please use a recent OpenShift 4.8+ cluster (either CodeReady Containers or SNO). And install OpenShift Serverless.

• Install person-service helm chart
• Click on "Make serverless"
• Add an environment variable APP_GREETING with some nice content
• Click on Edit Service to make the ksvc use the database:

          envFrom:
            - prefix: DB_
              secretRef:
                name: ps1-db-pguser-ps1-db

• Demonstrate that it works now.
• Wait a bit until it settled down

• Go to the console
• Deploy a new version

kn service update ksvc-ps1-deployment --image=quay.io/wpernath/person-service:v1.8.10-jvm --env APP_GREETING="We are now in JVM mode"
kn revision list
https --verify=no ....

• Tag the two (useable) revisions

kn service update ksvc-ps1-deployment --tag=ksvc-ps1-deployment-00003=jvm
kn service update ksvc-ps1-deployment --tag=ksvc-ps1-deployment-00002=native
kn revision list

• Now update the service to get only one or the other tag (A/B deployments)

kn service update ksvc-ps1-deployment --traffic native=100,jvm=0
kn service update ksvc-ps1-deployment --traffic native=0,jvm=100

• The only difference to A/B is that we are going to have traffic splits between the old and the new version

kn service update ksvc-ps1-deployment --traffic native=80,jvm=20
watch -n1 http ....

• New namespace
• Create the knative helm chart
• Install it twice with --set deployment.tag=jvm|native

helm package knative-chart
helm install ps1-native <chart-file>
helm install ps1-jvm <chart-file> --set deployment.tag=jvm

• Do load test with hey

hey -T application/json -c 16 -n 32000 <url>