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Chat Kubernetes (Stage 7)

Local Kubernetes deployment with kind and Tilt

Overview​

This example deploys the same containerized chat application to a local Kubernetes cluster. You'll write Deployments, Services, and Ingress manifests — the same resources that run in production on k3s or any managed Kubernetes provider.

Why this matters:

  • Understand Kubernetes primitives (Pods, Deployments, Services, Ingress)
  • Learn the kind + Tilt development workflow
  • See how Kustomize manages environment differences
  • Same manifests work locally and in production

What You'll Learn​

  • Kubernetes Manifests: Deployments, Services, ConfigMaps, Ingress
  • kind: Local Kubernetes clusters inside Docker
  • Tilt: Automated build-deploy-reload for K8s development
  • Kustomize: Environment overlays without templating
  • Traefik Ingress: Path-based routing in Kubernetes

Prerequisites​

Project Structure​

20-chat-kubernetes/
├── client/                     # Same as Docker Compose example
├── server/                     # Same as Docker Compose example
├── k8s/
│   ├── base/
│   │   ├── kustomization.yaml
│   │   ├── backend-deployment.yaml
│   │   ├── frontend-deployment.yaml
│   │   ├── postgres-statefulset.yaml
│   │   ├── services.yaml
│   │   ├── configmap.yaml
│   │   └── ingress.yaml        # ingressClassName: traefik
│   └── overlays/
│       ├── development/        # Debug logging
│       └── production/         # 3 replicas, warn logging
├── Tiltfile                    # Build + deploy + watch
├── kind-config.yaml            # Cluster with port mappings
└── traefik-values.yaml         # Helm values for ingress

Quick Start​

cd examples/20-chat-kubernetes

# 1. Create cluster
kind create cluster --name chat-dev --config kind-config.yaml

# 2. Install Traefik ingress controller
helm repo add traefik https://traefik.github.io/charts
helm repo update
helm install traefik traefik/traefik -f traefik-values.yaml

# 3. Start Tilt (builds, deploys, watches for changes)
tilt up
  • Tilt dashboard: http://localhost:10350
  • Frontend: http://localhost:8080
  • Backend API: http://localhost:3001/api/health

Key Concepts​

1. Declarative State​

You describe what you want; Kubernetes makes it happen:

spec:
  replicas: 3    # "I want 3 copies"

If a Pod crashes, Kubernetes creates a replacement automatically.

2. Kustomize Overlays​

Same base manifests, different settings per environment:

# k8s/overlays/production/kustomization.yaml
patches:
  - patch: |-
      apiVersion: apps/v1
      kind: Deployment
      metadata:
        name: chat-backend
      spec:
        replicas: 3

3. Ingress Routing​

Traefik routes external traffic to internal Services:

spec:
  ingressClassName: traefik
  rules:
    - http:
        paths:
          - path: /api    → chat-backend
          - path: /       → chat-frontend

Curriculum Alignment​

This example aligns with:

  • Module 19: Containerization & Orchestration — Kubernetes fundamentals

Source Code​

View the complete source: examples/20-chat-kubernetes/