k8s-helm-charts

Helm charts for application deployments in Kubernetes

Overview

This repository contains reusable Helm charts for deploying various types of applications and databases in Kubernetes clusters. Each chart is designed with best practices and includes support for monitoring, secrets management, and routing.

Available Charts

• client_app - Static frontend applications (nginx-based)
• node_app - Node.js backend applications
• spring_app - Spring Boot Java applications
• postgres_db - PostgreSQL database with monitoring
• redis - Redis session store for oauth2-proxy

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client_app

Deploys a static frontend application using nginx, suitable for React, Vue, Angular, or other client-side applications.

Required Values

Parameter	Description	Example
image	Container image for the application	myregistry.io/my-app:1.0.0
appPort	Application port (nginx port)	80
metricsPort	Metrics exporter port	8085
host	Hostname for the HTTPRoute	myapp.example.com

Optional Values

Parameter	Description	Example	Default
basePath	Base path prefix for the application	/app	-
env	Environment variables as key-value pairs	See example below	{}

Example values.yaml

image: myregistry.io/my-frontend-app:1.0.0
appPort: 80
metricsPort: 8085
host: myapp.example.com
basePath: /dashboard
env:
  API_URL: https://api.example.com
  FEATURE_FLAG: "true"

---

node_app

Deploys a Node.js backend application with support for Azure Workload Identity and environment variables.

Required Values

Parameter	Description	Example
image	Container image for the application	myregistry.io/my-node-app:1.0.0
appPort	Application port	8080
host	Hostname for the HTTPRoute	api.example.com
serviceAccountName	Kubernetes service account name	my-app-sa
clientId	Azure AD client ID for workload identity	12345678-1234-1234-1234-123456789abc

Optional Values

Parameter	Description	Example	Default
basePath	Base path prefix for the application	/api	-
env	Environment variables as key-value pairs	See example below	{}

Example values.yaml

image: myregistry.io/my-node-app:1.0.0
appPort: 8080
host: api.example.com
basePath: /api/v1
serviceAccountName: my-node-app-sa
clientId: 12345678-1234-1234-1234-123456789abc
env:
  DATABASE_URL: postgresql://localhost:5432/mydb
  LOG_LEVEL: info
  NODE_ENV: production

---

spring_app

Deploys a Spring Boot application with support for Spring Boot Actuator, Azure Workload Identity, config files, and persistent storage.

Required Values

Parameter	Description	Example
image	Container image for the application	myregistry.io/my-spring-app:1.0.0
appPort	Application port	8080
springActuatorPort	Spring Actuator management port	8082
host	Hostname for the HTTPRoute	api.example.com
serviceAccountName	Kubernetes service account name	my-app-sa
clientId	Azure AD client ID for workload identity	12345678-1234-1234-1234-123456789abc
springAdminServerHost	Spring Boot Admin server hostname	spring-admin.example.com
springAdminServerPort	Spring Boot Admin server port	8080

Optional Values

Parameter	Description	Example	Default
basePath	Base path prefix for the application	/api	-
env	Environment variables as key-value pairs	See example below	{}
configFile	Array of config files to mount as secrets	See example below	[]
persistentVolumeClaims	Array of PVCs to create and mount	See example below	[]

Config File Structure

Each config file entry supports:

Field	Description	Required
name	File name	Yes
mountPath	Full path where the file should be mounted	Yes
data	Base64-encoded file contents	Yes

Persistent Volume Claim Structure

Each PVC entry supports:

Field	Description	Required	Example
name	PVC identifier (unique name)	Yes	data
mountPath	Mount path in the container	Yes	/data
accessMode	Access mode for the volume	Yes	ReadWriteOnce
storageClassName	Storage class name	Yes	standard
volumeName	Persistent volume name to bind to	Yes	pv-data
storage	Storage size	Yes	10Gi

Example values.yaml

image: myregistry.io/my-spring-app:1.0.0
appPort: 8080
springActuatorPort: 8082
host: api.example.com
basePath: /api
serviceAccountName: my-spring-app-sa
clientId: 12345678-1234-1234-1234-123456789abc
springAdminServerHost: spring-admin.example.com
springAdminServerPort: 8080

env:
  SPRING_PROFILES_ACTIVE: production
  DATABASE_URL: postgresql://localhost:5432/mydb

configFile:
  - name: application.properties
    mountPath: /config/application.properties
    data: c3ByaW5nLmRhdGFzb3VyY2UudXJsPWpkYmM6cG9zdGdyZXNxbDovL2xvY2FsaG9zdDo1NDMyL215ZGI=
  - name: logback.xml
    mountPath: /config/logback.xml
    data: PGNvbmZpZ3VyYXRpb24+PC9jb25maWd1cmF0aW9uPg==

persistentVolumeClaims:
  - name: data
    mountPath: /data
    accessMode: ReadWriteOnce
    storageClassName: standard
    volumeName: pv-data
    storage: 10Gi
  - name: logs
    mountPath: /var/log/app
    accessMode: ReadWriteOnce
    storageClassName: standard
    volumeName: pv-logs
    storage: 5Gi

---

postgres_db

Deploys a PostgreSQL database with Prometheus metrics exporter and persistent storage.

Required Values

Parameter	Description	Example
name	Database name	myappdb
port	PostgreSQL port	5432
metricsPort	Prometheus exporter port	8085
username	Database username (stored as secret)	myuser
password	Database password (stored as secret)	mypassword
exporterUsername	Prometheus exporter username	exporter
exporterPassword	Prometheus exporter password	exporterpass

Optional Values

Parameter	Description	Example	Default
initSql	SQL script to run on database initialization	CREATE TABLE users (id SERIAL);	""
persistentVolumeClaim	Persistent volume claim configuration object	See below	See below

Persistent Volume Claim Configuration

The persistentVolumeClaim parameter accepts an object with the following fields:

Field	Description	Example	Default
accessMode	Access mode for the volume	ReadWriteOnce	ReadWriteOnce
storageClassName	Storage class name for the PVC	standard	""
volumeName	Persistent volume name to bind to	pv-postgres-data	""
storage	Storage size	10Gi	1Gi

Features

• PostgreSQL 18.4 with configurable persistent storage
• Prometheus metrics exporter for monitoring
• Automatic database initialization with custom SQL
• Automatic creation of exporter user with pg_monitor role
• Service monitor for Prometheus integration

Example values.yaml

name: myappdb
port: 5432
metricsPort: 8085
username: myuser
password: securepassword123
exporterUsername: exporter
exporterPassword: exporterpass456
initSql: |
  CREATE TABLE users (
    id SERIAL PRIMARY KEY,
    username VARCHAR(255) NOT NULL,
    created_at TIMESTAMP DEFAULT NOW()
  );
  CREATE INDEX idx_username ON users(username);
persistentVolumeClaim:
  accessMode: ReadWriteOnce
  storageClassName: standard
  volumeName: pv-postgres-data
  storage: 10Gi

---

redis

Deploys a single-instance Redis suitable for use as a session store for oauth2-proxy.

Required Values

Parameter	Description	Example
password	Redis AUTH password (stored as a secret)	changeme

Optional Values

Parameter	Description	Example	Default
port	Service port for Redis	6379	6379
resources	Container resource requests/limits	See below	See below
persistentVolumeClaim	PVC configuration object	See below	See below

Persistent Volume Claim Configuration

Field	Description	Example	Default
accessMode	Access mode for the volume	ReadWriteOnce	ReadWriteOnce
storageClassName	Storage class name for the PVC	standard	""
volumeName	Persistent volume name to bind to	pv-redis-data	""
storage	Storage size	1Gi	1Gi

Features

• Redis 8.8 with AOF persistence enabled
• Password authentication via Kubernetes secret
• Persistent storage for session durability across restarts
• TCP liveness and authenticated readiness probes

Example values.yaml

password: changeme
port: 6379
persistentVolumeClaim:
  accessMode: ReadWriteOnce
  storageClassName: standard
  volumeName: pv-redis-data
  storage: 1Gi

Using with oauth2-proxy

Configure oauth2-proxy with the following arguments:

--session-store-type=redis
--redis-connection-url=redis://:<password>@<release-name>.<namespace>.svc.cluster.local:6379

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Common Features

Monitoring

All charts include:

• ServiceMonitor resources for Prometheus integration
• Metrics endpoints properly configured
• Health check probes (where applicable)

Security

• Secrets management for sensitive data
• Azure Workload Identity support (node_app, spring_app)
• Service accounts with proper permissions

Routing

• Kubernetes Gateway API HTTPRoute resources
• Support for path-based and host-based routing
• Attaches to the shared traefik Gateway (websecure listener)

Resource Management

• Sensible resource requests and limits
• Configurable deployment parameters
• Liveness and startup probes

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Usage

Installing a Chart

helm install my-release ./charts/spring_app -f my-values.yaml

Upgrading a Release

helm upgrade my-release ./charts/spring_app -f my-values.yaml

Uninstalling a Release

helm uninstall my-release

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