Deliver with Helm

Here's how to deliver podtato-head using Helm.

Prerequisites

• Install Helm (official instructions)

Deliver

You must clone this repo and install from a local copy of the chart:

git clone https://github.com/podtato-head/podtato-head.git && cd podtato-head
helm install podtato-head ./delivery/chart

This will install the chart in this directory with release name podtato-head.

NOTE: You can instruct helm to wait for the resources to be ready before marking the release as successful by adding the --wait option to the previous command.

The installation can be customized by changing the following parameters via --set or a custom values.yaml file specified with --values:

Parameter	Description	Default
replicaCount	Number of replicas of the container	1
images.repositoryDirname	Prefix for image repos	ghcr.io/podtato-head
images.pullPolicy	Podtato Head Container pull policy	IfNotPresent
images.pullSecrets	Podtato Head Pod pull secret	[]
<service>.repositoryBasename	Leaf part of name of image repo for	entry, hat, etc.
<service>.tag	Tag of image repo for	0.1.0
<service>.serviceType	Service type for	LoadBalancer for main
<service>.servicePort	Service port for	9000-9005
<service>.env	Add "env:" entries on Deployments (ex: PODTATO_PART_NUMBER)	[]
serviceAccount.create	Whether or not to create dedicated service account	true
serviceAccount.name	Name of the service account to use	default
serviceAccount.annotations	Annotations to add to a created service account	{}
podAnnotations	Map of annotations to add to the pods	{}
ingress.enabled	Enables Ingress	false
ingress.className	IngressClass that will be be used (Kubernetes 1.18+)	""
ingress.annotations	Ingress annotations	{}
ingress.hosts	Ingress accepted hostnames	[]
ingress.tls	Ingress TLS configuration	[]
autoscaling.enabled	Enable horizontal pod autoscaler	false
autoscaling.targetCPUUtilizationPercentage	Target CPU utilization	80
autoscaling.targetMemoryUtilizationPercentage	Target Memory utilization	80
autoscaling.minReplicas	Min replicas for autoscaling	1
autoscaling.maxReplicas	Max replicas for autoscaling	100
tolerations	List of node taints to tolerate	[]
resources	Resource requests and limits	{}
nodeSelector	Labels for pod assignment	{}

Test

Verify the release succeeded:

helm list
kubectl get pods
kubectl get services

Test the API endpoint

To connect to the API you'll first need to determine the correct address and port.

If using a LoadBalancer-type service for entry, get the IP address of the load balancer and use port 9000:

ADDR=$(kubectl get service podtato-head-entry -o jsonpath='{.status.loadBalancer.ingress[0].ip}')
PORT=9000

If using a NodePort-type service, get the address of a node and the service's NodePort as follows:

NODE_NAME=$(kubectl get nodes --output json | jq -r '.items[].metadata.name' | head -n 1)
ADDR=$(kubectl get nodes ${NODE_NAME} -o jsonpath={.status.addresses[0].address})
PORT=$(kubectl get services podtato-head-entry -ojsonpath='{.spec.ports[0].nodePort}')

If using a ClusterIP-type service, run kubectl port-forward in the background and connect through that:

NOTE: Find and kill the port-forward process afterwards using ps and kill.

# Choose below the IP address of your machine you want to use to access application 
ADDR=127.0.0.1
# Choose below the port of your machine you want to use to access application 
PORT=9000
kubectl port-forward --address ${ADDR} svc/podtato-head-entry ${PORT}:9000 &

Now test the API itself with curl and/or a browser:

curl http://${ADDR}:${PORT}/
xdg-open http://${ADDR}:${PORT}/

Update

To update the application version, you can choose one of the following methods :

• update <service>.tag in values.yaml for each service and run helm upgrade podtato-head ./delivery/chart
• run helm upgrade podtato-head ./delivery/chart --set entry.tag=0.1.1 --set leftLeg.tag=0.1.1 ...

A new revision is then installed.

NOTE : to ensure idempotency between the first installation and the following updates, you should use the following command :

helm upgrade --install podtato-head ./delivery/chart

Rollback

To rollback to a previous revision, run :

# Check revision history
helm history podtato-head

# Rollback to the revision 1
helm rollback podtato-head 1

# Check the revision
helm status podtato-head

Uninstall

helm uninstall podtato-head