Kubernetes & Helm Patterns
Helm Chart Structure
helm/orca-facade/
├── Chart.yaml
├── values.yaml
├── values-dev.yaml
├── values-prod.yaml
├── templates/
│ ├── _helpers.tpl
│ ├── deployment.yaml
│ ├── service.yaml
│ ├── ingress.yaml
│ ├── configmap.yaml
│ ├── secret.yaml
│ ├── hpa.yaml
│ └── serviceaccount.yaml
└── charts/ # Dependencies
Chart.yaml
apiVersion: v2
name: orca-facade
description: Orca Facade API Service
type: application
version: 1.0.0
appVersion: "1.0.0"
dependencies:
- name: postgresql
version: "12.x.x"
repository: "https://charts.bitnami.com/bitnami"
condition: postgresql.enabled
values.yaml
# Image configuration
image:
repository: registry.example.com/orca-facade
tag: latest
pullPolicy: IfNotPresent
# Replica configuration
replicaCount: 2
# Resource limits
resources:
requests:
cpu: 100m
memory: 256Mi
limits:
cpu: 500m
memory: 512Mi
# Service configuration
service:
type: ClusterIP
port: 80
targetPort: 8080
grpcPort: 8081
# Ingress
ingress:
enabled: true
className: nginx
annotations:
cert-manager.io/cluster-issuer: letsencrypt-prod
hosts:
- host: orca.example.com
paths:
- path: /
pathType: Prefix
tls:
- secretName: orca-tls
hosts:
- orca.example.com
# Environment variables
env:
SPRING_PROFILES_ACTIVE: k8s
SERVER_PORT: "8080"
# Secrets (reference external secrets)
secrets:
DATABASE_URL:
secretName: orca-db-credentials
key: url
JWT_SECRET:
secretName: orca-jwt
key: secret
# Health checks
health:
livenessProbe:
httpGet:
path: /actuator/health/liveness
port: 8080
initialDelaySeconds: 30
periodSeconds: 10
readinessProbe:
httpGet:
path: /actuator/health/readiness
port: 8080
initialDelaySeconds: 10
periodSeconds: 5
# Autoscaling
autoscaling:
enabled: true
minReplicas: 2
maxReplicas: 10
targetCPUUtilizationPercentage: 70
# PostgreSQL subchart
postgresql:
enabled: false # Use external database
Deployment Template
# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
name: {{ include "orca-facade.fullname" . }}
labels:
{{- include "orca-facade.labels" . | nindent 4 }}
spec:
{{- if not .Values.autoscaling.enabled }}
replicas: {{ .Values.replicaCount }}
{{- end }}
selector:
matchLabels:
{{- include "orca-facade.selectorLabels" . | nindent 6 }}
template:
metadata:
annotations:
checksum/config: {{ include (print $.Template.BasePath "/configmap.yaml") . | sha256sum }}
labels:
{{- include "orca-facade.selectorLabels" . | nindent 8 }}
spec:
serviceAccountName: {{ include "orca-facade.serviceAccountName" . }}
containers:
- name: {{ .Chart.Name }}
image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
imagePullPolicy: {{ .Values.image.pullPolicy }}
ports:
- name: http
containerPort: {{ .Values.service.targetPort }}
protocol: TCP
- name: grpc
containerPort: {{ .Values.service.grpcPort }}
protocol: TCP
env:
{{- range $key, $value := .Values.env }}
- name: {{ $key }}
value: {{ $value | quote }}
{{- end }}
{{- range $key, $secret := .Values.secrets }}
- name: {{ $key }}
valueFrom:
secretKeyRef:
name: {{ $secret.secretName }}
key: {{ $secret.key }}
{{- end }}
{{- with .Values.health.livenessProbe }}
livenessProbe:
{{- toYaml . | nindent 12 }}
{{- end }}
{{- with .Values.health.readinessProbe }}
readinessProbe:
{{- toYaml . | nindent 12 }}
{{- end }}
resources:
{{- toYaml .Values.resources | nindent 12 }}
Service Template
# templates/service.yaml
apiVersion: v1
kind: Service
metadata:
name: {{ include "orca-facade.fullname" . }}
labels:
{{- include "orca-facade.labels" . | nindent 4 }}
spec:
type: {{ .Values.service.type }}
ports:
- port: {{ .Values.service.port }}
targetPort: http
protocol: TCP
name: http
- port: {{ .Values.service.grpcPort }}
targetPort: grpc
protocol: TCP
name: grpc
selector:
{{- include "orca-facade.selectorLabels" . | nindent 4 }}
ConfigMap Template
# templates/configmap.yaml
apiVersion: v1
kind: ConfigMap
metadata:
name: {{ include "orca-facade.fullname" . }}-config
labels:
{{- include "orca-facade.labels" . | nindent 4 }}
data:
application.yaml: |
spring:
profiles:
active: k8s
server:
port: {{ .Values.service.targetPort }}
management:
endpoints:
web:
exposure:
include: health,info,prometheus
Helper Templates
# templates/_helpers.tpl
{{- define "orca-facade.name" -}}
{{- default .Chart.Name .Values.nameOverride | trunc 63 | trimSuffix "-" }}
{{- end }}
{{- define "orca-facade.fullname" -}}
{{- if .Values.fullnameOverride }}
{{- .Values.fullnameOverride | trunc 63 | trimSuffix "-" }}
{{- else }}
{{- $name := default .Chart.Name .Values.nameOverride }}
{{- printf "%s-%s" .Release.Name $name | trunc 63 | trimSuffix "-" }}
{{- end }}
{{- end }}
{{- define "orca-facade.labels" -}}
helm.sh/chart: {{ .Chart.Name }}-{{ .Chart.Version }}
app.kubernetes.io/name: {{ include "orca-facade.name" . }}
app.kubernetes.io/instance: {{ .Release.Name }}
app.kubernetes.io/version: {{ .Chart.AppVersion | quote }}
app.kubernetes.io/managed-by: {{ .Release.Service }}
{{- end }}
{{- define "orca-facade.selectorLabels" -}}
app.kubernetes.io/name: {{ include "orca-facade.name" . }}
app.kubernetes.io/instance: {{ .Release.Name }}
{{- end }}
HorizontalPodAutoscaler
# templates/hpa.yaml
{{- if .Values.autoscaling.enabled }}
apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
name: {{ include "orca-facade.fullname" . }}
labels:
{{- include "orca-facade.labels" . | nindent 4 }}
spec:
scaleTargetRef:
apiVersion: apps/v1
kind: Deployment
name: {{ include "orca-facade.fullname" . }}
minReplicas: {{ .Values.autoscaling.minReplicas }}
maxReplicas: {{ .Values.autoscaling.maxReplicas }}
metrics:
- type: Resource
resource:
name: cpu
target:
type: Utilization
averageUtilization: {{ .Values.autoscaling.targetCPUUtilizationPercentage }}
{{- end }}
Helm Commands
# Install/Upgrade
helm upgrade --install orca-facade ./helm/orca-facade \
-f ./helm/orca-facade/values-prod.yaml \
--namespace orca \
--create-namespace
# Dry run
helm upgrade --install orca-facade ./helm/orca-facade \
--dry-run --debug
# Template only (see generated YAML)
helm template orca-facade ./helm/orca-facade -f values-prod.yaml
# Lint chart
helm lint ./helm/orca-facade
# Rollback
helm rollback orca-facade 1 --namespace orca
# History
helm history orca-facade --namespace orca
# Uninstall
helm uninstall orca-facade --namespace orca
kubectl Commands
# Get pods
kubectl get pods -n orca -l app.kubernetes.io/name=orca-facade
# Logs
kubectl logs -n orca -l app.kubernetes.io/name=orca-facade --tail=100 -f
# Describe deployment
kubectl describe deployment orca-facade -n orca
# Port forward for local testing
kubectl port-forward -n orca svc/orca-facade 8080:80
# Exec into pod
kubectl exec -it -n orca deployment/orca-facade -- /bin/sh
# Apply manually
kubectl apply -f k8s/configmap.yaml -n orca
