Helm charts for Navida Pro

Structure

The backend services as of now contains a directory called CD and under this directory you can find a sub directory called templates which contains the template yaml files for mainly

• deployment
• configmaps
• services
• hpa ( horizontal pod autoscaling)
• service monitor
• service account

mychart/
├── Chart.yaml
├── values.yaml
├── templates/
│   ├── deployment.yaml
│   ├── configmap.yaml
│   ├── service.yaml
│   ├── hpa.yaml
│   ├── servicemonitor.yaml
│   └── serviceaccount.yaml
└── ...

actual structure and tempaltes from one of the backend service are used for explaining the below :

Templates

Deployment template :

A Deployment provides declarative updates for Pods and ReplicaSets. You describe a desired state in a Deployment, and the Deployment Controller changes the actual state to the desired state at a controlled rate.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "helm-chart.fullname" . }}
  labels:
    {{- include "helm-chart.labels" . | nindent 4 }}
spec:
  {{- if not .Values.autoscaling.enabled }}
  replicas: {{ .Values.replicaCount }}
  {{- end }}
  revisionHistoryLimit: {{ .Values.revisionHistoryLimit}}
  selector:
    matchLabels:
      {{- include "helm-chart.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      {{- with .Values.podAnnotations }}
      annotations:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      labels:
        {{- include "helm-chart.selectorLabels" . | nindent 8 }}
    spec:
      {{- with .Values.imagePullSecrets }}
      imagePullSecrets:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      serviceAccountName: {{ include "helm-chart.serviceAccountName" . }}
      securityContext:
        {{- toYaml .Values.podSecurityContext | nindent 8 }}  

      volumes:
      - name: "{{ .Chart.Name }}-kafka-cert-volume"
        emptyDir: {}
      - name: all-ca-certs-config
        configMap:
          name: {{ .Values.caCertsConfigMap }}
      - name: application-config
        configMap:
          name: {{ include "helm-chart.fullname" . }}-properties
          items:
              - key: application.properties
                path: application.properties
      initContainers:
        - name: "{{ .Chart.Name }}-kafka-cert-prep"
          image: "{{ .Values.init_image.kafkaCertPrepImage }}"
          command: ["/bin/sh", "-c"]          
          args:
          - |
              for cert in /tmp/certs/*
              do
                alias=$(basename $cert | cut -f 1 -d '.')
                keytool -import -file $cert -alias $alias -keystore /etc/kafka/certs/${alias}.jks -storepass "{{ .Values.env.javax.net.ssl.trustStorePassword }}" -noprompt
                keytool -importkeystore -srckeystore /etc/kafka/certs/${alias}.jks -destkeystore /etc/kafka/certs/navida.truststore.jks -srcstorepass "{{ .Values.env.javax.net.ssl.trustStorePassword }}" -deststorepass "{{ .Values.env.javax.net.ssl.trustStorePassword }}"
              done
          volumeMounts:
            - name: "{{ .Chart.Name }}-kafka-cert-volume"
              mountPath: "/etc/kafka/certs"
            - name: all-ca-certs-config
              mountPath: "/tmp/certs"
              readOnly: false                    
      containers:
        - name: {{ .Chart.Name }}
          securityContext:
            {{- toYaml .Values.securityContext | nindent 12 }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag | default .Chart.AppVersion }}"
          imagePullPolicy: {{ .Values.image.pullPolicy }}
          env:
          {{- include "toFlatEnv" (dict "keys" (list) "value" .Values.env) | nindent 12 }}
          ports:
            - name: {{ .Values.ports.name }}
              containerPort: {{ .Values.ports.containerPort }}
              protocol: {{ .Values.ports.protocol }}
          resources:
            {{- toYaml .Values.resources | nindent 12 }}
          livenessProbe:
            {{- with .Values.livenessProbe}}
            initialDelaySeconds: {{ .initialDelaySeconds }}
            periodSeconds: {{ .periodSeconds }}
            timeoutSeconds: {{ .timeoutSeconds }}
            {{- end}}
            httpGet:
              path: {{ .Values.livenessProbe.path }}
              port: {{ .Values.service.port}}
              scheme: HTTP
          readinessProbe:
            {{- with .Values.readinessProbe}}
            initialDelaySeconds: {{ .initialDelaySeconds }}
            periodSeconds: {{ .periodSeconds }}
            timeoutSeconds: {{ .timeoutSeconds }}
            {{- end}}
            httpGet:
              path: {{ .Values.readinessProbe.path }}
              port: {{ .Values.service.port }}
              scheme: HTTP
          volumeMounts:
            - name: application-config 
              mountPath: "/app/resources/application.properties"
              subPath: application.properties 
              readOnly: true
            - name: "{{ .Chart.Name }}-kafka-cert-volume"
              mountPath: "/navida.truststore.jks"   
              subPath: navida.truststore.jks 
            - name: "{{ .Chart.Name }}-kafka-cert-volume"
              mountPath: "/app/resources/navida.truststore.jks"   
              subPath: navida.truststore.jks
      
         
      {{- with .Values.nodeSelector }}
      nodeSelector:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      {{- with .Values.affinity }}
      affinity:
        {{- toYaml . | nindent 8 }}
      {{- end }}
      {{- with .Values.tolerations }}
      tolerations:
        {{- toYaml . | nindent 8 }}
      {{- end }}

ConfigMap template :

ConfigMaps allow you to decouple configuration artifacts from image content to keep containerized applications portable.

Service template :

A Service in Kubernetes is an abstraction which defines a logical set of Pods and a policy by which to access them.

HPA template :

The Horizontal Pod Autoscaler automatically scales the number of pods in a replication controller, deployment, or replica set based on observed CPU utilization.

Service monitor template :

ServiceMonitor is a resource in the monitoring.coreos.com group that tells the Prometheus operator which services should be monitored.

Service Account template :

A ServiceAccount provides an identity for processes that run in a Pod.