Solution

.infrastructure/helm-chart/Chart.yaml

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+apiVersion: v2
+name: todoapp
+description: A Helm chart for Kubernetes
+type: application
+version: 0.1.0

.infrastructure/helm-chart/Chart.yml

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+apiVersion: v2
+name: todoapp
+description: A Helm chart for Kubernetes
+type: application
+version: 0.1.0

.infrastructure/helm-chart/charts/mysql/Chart.yml

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+apiVersion: v2
+name: mysql
+description: A Helm chart for Kubernetes
+type: application
+version: 0.1.0

.infrastructure/helm-chart/charts/mysql/templates/configMap.yml

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+apiVersion: v1
+kind: ConfigMap
+metadata:
+    name: {{ .Chart.Name }}-configMap
+    namespace: {{ .Values.namespace.mysql.name }}
+    labels:
+        app: mysql
+data:
+  init.sql: |
+    GRANT ALL PRIVILEGES ON app_db.* TO 'app_user'@'%';
+    USE app_db;
+    CREATE TABLE counter (
+        id INT AUTO_INCREMENT PRIMARY KEY,
+        value INT
+    );

.infrastructure/helm-chart/charts/mysql/templates/ns.yml

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+apiVersion: v1
+kind: Namespace
+metadata:
+    name: {{ .Values.namespace.mysql.name }}

.infrastructure/helm-chart/charts/mysql/templates/secret.yml

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+apiVersion: v1
+kind: Secret
+metadata:
+    name: {{ .Chart.Name }}-secrets
+    namespace: {{ .Values.global.namespace }}
+type: Opaque
+data:
+{{- range $key, $val := .Values.mysql.secret }}
+    {{ $key | upper }}: {{ $val | b64enc | quote}}
+{{- end }}

.infrastructure/helm-chart/charts/mysql/templates/service.yml

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+apiVersion: v1
+kind: Service
+metadata:
+    name: {{ .Chart.Name}}-service
+    namespace: {{ .Values.namespace.mysql.name }}
+spec:
+    selector:
+        app: mysql
+    ports:
+        - name: mysql
+        port: 3306
+    clusterIP: None

.infrastructure/helm-chart/charts/mysql/templates/statefulSet.yml

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+apiVersion: apps/v1
+kind: StatefulSet
+metadata:
+	name: {{ .Chart.Name }}-statefulSet
+	namespace: {{ .Values.namespace.mysql.name }}
+spec:
+	selector:
+		matchLabels:
+			app: mysql
+	replicas: {{ .Values.hpa.mysql.minReplicas }}
+	serviceName: mysql
+	template:
+		metadata:
+			labels:
+				app: mysql
+		spec:
+			containers:
+			- name: mysql
+				image: {{ .Values.image.mysql.repository }}:{{ .Values.image.mysql.tag }}
+				env:
+                {{- range $v, $k := .Values.mysql.secret }}
+				- name: {{ $v }}
+					valueFrom:
+						secretKeyRef:
+							name: {{ $v }}
+							key: {{ $k | b64enc | quote }}
+                {{- end }}
+				- name: value
+					value: app_db
+				ports:
+				- name: mysql
+					containerPort: 3306
+				volumeMounts:
+				- name: data
+					mountPath: /var/lib/mysql
+					subPath: mysql
+				- name: config-map
+					mountPath: /docker-entrypoint-initdb.d
+				resources:
+					requests:
+						cpu: {{ .Values.mysql.resources.limits.cpu }}
+						memory: {{ .Values.mysql.resources.limits.memory }}
+				livenessProbe:
+					exec:
+						command: ["mysqladmin", "ping"]
+					initialDelaySeconds: 30
+					periodSeconds: 10
+					timeoutSeconds: 5
+				readinessProbe:
+					exec:
+						command: ["mysqladmin", "ping"]
+					initialDelaySeconds: 5
+					periodSeconds: 2
+					timeoutSeconds: 1
+			volumes:
+			- name: config-map
+				configMap:
+					name: {{ .Values.mysql.affinity.nodeAffinity.values }}
+			tolerations:
+			- key: {{ .Values.mysql.affinity.nodeAffinity.key }}
+				operator: "Equal"
+				value: "mysql"
+				effect: "NoSchedule"
+			affinity:
+				podAntiAffinity:
+					requiredDuringSchedulingIgnoredDuringExecution:
+					- labelSelector:
+							matchExpressions:
+							- key: {{ .Values.mysql.affinity.nodeAffinity.key }}
+								operator: In
+								values:
+								- {{ .Values.mysql.affinity.nodeAffinity.values }}
+					topologyKey: "kubernetes.io/hostname"
+				nodeAffinity:
+					requiredDuringSchedulingIgnoredDuringExecution:
+						nodeSelectorTerms:
+						- matchExpressions:
+							- key: {{ .Values.mysql.affinity.nodeAffinity.key }}
+								operator: In
+								values:
+								- {{ .Values.mysql.affinity.nodeAffinity.values }}
+	volumeClaimTemplates:
+	- metadata:
+			name: data
+		spec:
+			accessModes: ["ReadWriteOnce"]
+			resources:
+				requests:
+					storage: {{ .Values.mysql.resources.requests.storage }}

.infrastructure/helm-chart/charts/mysql/values.yml

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+namespace:
+  mysql:
+    name: mysql-helm
+mysql:
+  secret:
+      MYSQL_ROOT_PASSWORD: "MTIzNA=="
+      MYSQL_USER: "YXBwX3VzZXI="
+      MYSQL_PASSWORD: "MTIzNA=="
+  resources:
+      requests:
+        cpu: "100m"
+        memory: "128Mi"
+        storage: "2Gi"
+      limits:
+        cpu: "500m"
+        memory: "1Gi"
+
+  rollingUpdate:
+      maxUnavailable: 25%
+      maxSurge: 25%
+
+  affinity:
+      nodeAffinity:
+        key: "app"
+        values: mysql
+
+
+image:
+  mysql:
+    repository: mysql
+    tag: "8.0"
+
+hpa:
+  mysql:
+    minReplicas: 2
+    maxReplicas: 10
+    cpuUtilization: 50
+    memoryUtilization: 70
+
+persistentVolume:
+  capacity: "1Gi"
+
+persistentVolumeClaim:
+  storage: "1Gi"
+
+serviceAccount: mysql

.infrastructure/helm-chart/templates/clusterIp.yml

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+apiVersion: v1
+kind: Service
+metadata:
+	name: {{ .Chart.Name }}-clusterIp
+	namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+	type: ClusterIP
+	selector:
+		app: todoapp
+	ports:
+	- protocol: TCP
+	  port: 80
+	  targetPort: 8080

.infrastructure/helm-chart/templates/configMap.yml

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+apiVersion: v1
+kind: ConfigMap
+metadata:
+    name: {{ .Chart.Name }}-configMap
+    namespace: {{ .Values.namespace.todoapp.name }}
+data:
+    PYTHONUNBUFFERED: "1"

.infrastructure/helm-chart/templates/deployment.yml

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+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: {{ .Chart.Name }}-deployment
+  namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+  strategy:
+    type: RollingUpdate
+    rollingUpdate:
+      maxSurge: {{ .Values.todoapp.rollingUpdate.maxSurge }}
+      maxUnavailable: {{ .Values.todoapp.rollingUpdate.maxUnavailable }}
+  selector:
+    matchLabels:
+      app: {{ .Chart.Name }}
+  template:
+    metadata:
+      labels:
+        app: {{ .Chart.Name }}
+    spec:
+      serviceAccountName: {{ .Chart.Name }}-secrets-reader
+      containers:
+      - name: todoapp
+        image: {{ .Values.image.todoapp.repository}}: {{.Values.image.todoapp.tag}}
+        volumeMounts:
+        - name: data
+          mountPath: /app/data
+        - name: app-secrets-volume
+          mountPath: "/app/secrets"
+          readOnly: true
+        - name: app-config-volume
+          mountPath: "/app/configs"
+          readOnly: true
+        resources:
+{{ toYaml .Values.todoapp.resources | nindent 12 }}
+        env:
+        - name: PYTHONUNBUFFERED
+          valueFrom:
+            configMapKeyRef:
+              name: {{ .Chart.Name }}-config
+              key: PYTHONUNBUFFERED
+        {{- range $v, $k := .Values.todoapp.secret }}
+        - name: {{ $k }}
+          valueFrom:
+            secretKeyRef:
+              name: {{ $v }}
+              key: {{ $k | b64enc | quote}}
+        {{- end }}
+        ports:
+        - containerPort: 8080
+        livenessProbe:
+          httpGet:
+            path: api/health
+            port: 8080
+          initialDelaySeconds: 60
+          periodSeconds: 5
+        readinessProbe:
+          httpGet:
+            path: api/ready
+            port: 8080
+          initialDelaySeconds: 5
+          periodSeconds: 5
+      volumes:
+      - name: data
+        persistentVolumeClaim:
+          claimName: pvc-data
+      - name: app-secrets-volume
+        secret:
+          secretName: app-secret
+      - name: app-config-volume
+        configMap:
+          name: app-config
+      affinity:
+        nodeAffinity:
+          preferredDuringSchedulingIgnoredDuringExecution:
+          - weight: 1
+            preference:
+              matchExpressions:
+              - key: {{ .Values.todoapp.affinity.nodeAffinity.key }}
+                operator: In
+                values:
+                - {{ .Values.todoapp.affinity.nodeAffinity.values }}

.infrastructure/helm-chart/templates/hpa.yml

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+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: {{ .Chart.Name }}-hpa
+  namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: todoapp
+  minReplicas: {{ .Values.hpa.todoapp.minReplicas }}
+  maxReplicas: {{ .Values.hpa.todoapp.maxReplicas }}
+  metrics:
+  - type: Resource
+    resource:
+      name: cpu
+      target:
+        type: Utilization
+        averageUtilization: {{ .Values.hpa.todoapp.cpuUtilization }}
+  - type: Resource
+    resource:
+      name: memory
+      target:
+        type: Utilization
+        averageUtilization: {{ .Values.hpa.todoapp.memoryUtilization }}

.infrastructure/helm-chart/templates/ingress.yml

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+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: {{ .Chart.Name }}-ingress
+  namespace: {{ .Values.todoapp.namespace }}
+  annotations:
+    nginx.ingress.kubernetes.io/rewrite-target: /$2
+spec:
+  rules:
+  - http:
+      paths:
+      - pathType: Prefix
+        path: /(|$)(.*)
+        backend:
+          service:
+            name: {{ .Chart.Name }}-service
+            port:
+              number: 80

.infrastructure/helm-chart/templates/nodeport.yml

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+apiVersion: v1
+kind: Service
+metadata:
+    name: {{ .Chart.Name }}-nodeport
+    namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+    type: NodePort
+    selector:
+        app: todoapp
+    ports:
+    - protocol: TCP
+      port: 80
+      targetPort: 8080
+      nodePort: 30007

.infrastructure/helm-chart/templates/ns.yml

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+apiVersion: v1
+kind: Namespace
+metadata:
+    name: {{ .Values.namespace.todoapp.name }}

.infrastructure/helm-chart/templates/pv.yml

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+apiVersion: v1
+kind: PersistentVolume
+metadata:
+    name: {{ .Chart.Name }}-pv
+    namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+    storageClassName: standard
+    persistentVolumeReclaimPolicy: Delete
+    accessModes:
+      - ReadWriteMany
+    capacity:
+        storage: {{ .Values.persistentVolume.todoapp.capacity }}
+    hostPath:
+        path: /data/

.infrastructure/helm-chart/templates/pvc.yml

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+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+    name: {{ .Chart.Name }}-pvc
+    namespace: {{ .Values.namespace.todoapp.name }}
+spec:
+    volumeName: pv-data
+    accessModes:
+    - ReadWriteMany
+    resources:
+        requests:
+            storage: {{ .Values.persistentVolumeClaim.todoapp.storage }}