Add Kubernetes Deployment Example

[lu-roth]

Add Kubernetes Deployment Example

Overview

This PR adds production-ready Kubernetes manifests for deploying Solidtime to any Kubernetes cluster, providing an alternative to the existing Docker Compose examples.

What's Included

Kubernetes Manifests:

• Namespace, Secrets, and ConfigMap for configuration
• PersistentVolumeClaim for shared storage
• App Deployment (2 replicas) with automatic database migrations
• Queue Worker Deployment for background jobs
• Scheduler CronJob for Laravel scheduled tasks
• Gotenberg service for PDF generation
• Ingress with automatic TLS certificate provisioning

Documentation:

• Quick start README following existing examples structure
• Comprehensive GUIDE with configuration, monitoring, and troubleshooting

Key Features

✅ Production-tested with external PostgreSQL database
✅ Automatic database migrations via init container
✅ High availability with 2 app replicas
✅ Proper Laravel scheduler implementation as CronJob
✅ Health checks and resource limits configured
✅ Well-documented with troubleshooting guide
✅ Template-based configuration (no sensitive data)

Technical Highlights

• Storage Strategy: PVC mounts at /var/www/html/storage/app to preserve framework directories from image
• Service Communication: Uses Kubernetes DNS (servicename.namespace.svc.cluster.local)
• Environment Variables: Matches docker-compose configuration with Kubernetes-specific adaptations

Testing

Deployed and verified on production cluster:

• ✅ All components working (app, queue, scheduler, gotenberg)
• ✅ Automatic migrations
• ✅ TLS certificate provisioning
• ✅ Multi-replica deployment with shared storage

Prerequisites for Users

• Kubernetes v1.19+
• Nginx Ingress Controller
• Cert-manager
• External PostgreSQL database
• ReadWriteMany storage class

This configuration enables Solidtime deployment on any Kubernetes platform (GKE, EKS, AKS, self-hosted) and is ready for use by the community.