# Podinfo — Go Microservice Template for Kubernetes

> Podinfo is a tiny Go microservice made for Kubernetes that showcases best practices for running workloads on K8s. It serves as a reference implementation for GitOps, progressive delivery, Helm charts, Kustomize overlays, and end-to-end testing of Kubernetes deployments.

## Install

Save as a script file and run:

# Podinfo — Go Microservice Template for Kubernetes

## Quick Use
```bash
# Deploy with kubectl
kubectl apply -k github.com/stefanprodan/podinfo//kustomize

# Or with Helm
helm repo add podinfo https://stefanprodan.github.io/podinfo
helm install podinfo podinfo/podinfo
```

## Introduction
Podinfo is a small Go web application designed to serve as a reference project for Kubernetes practitioners. Built by Stefan Prodan (creator of Flagger and Flux), it demonstrates how to structure a cloud-native microservice with health checks, graceful shutdown, Prometheus metrics, OpenTelemetry tracing, and 12-factor configuration. Teams use Podinfo as a starting point for GitOps pipelines, canary deployments, and Kubernetes platform validation.

## What Podinfo Does
- Provides HTTP and gRPC APIs with configurable responses for testing service mesh behavior
- Exposes Prometheus metrics, readiness and liveness probes, and structured logging
- Supports feature flags, fault injection, and latency simulation for chaos testing
- Includes Helm charts and Kustomize overlays for multi-environment deployment
- Serves as the standard demo app for Flux CD, Flagger, and other CNCF GitOps tools

## Architecture Overview
Podinfo is a single Go binary that runs an HTTP server and an optional gRPC server. It reads configuration from environment variables and command-line flags following 12-factor principles. The application exposes a REST API with endpoints for health, readiness, versioning, echo, and store operations (backed by an in-memory or Redis cache). Prometheus instrumentation is built in via the standard Go client library.

## Self-Hosting & Configuration
- Deploy via Helm chart, Kustomize overlay, or plain Kubernetes manifests
- Configure via environment variables: `PODINFO_PORT`, `PODINFO_GRPC_PORT`, `PODINFO_CACHE_SERVER`
- Enable Redis caching by setting the `--cache-server` flag to a Redis URL
- Customize the UI message, color, and logo through command-line flags or ConfigMaps
- Use the included Dockerfile for multi-arch container builds (amd64, arm64)

## Key Features
- Production-ready health check endpoints compatible with Kubernetes probes
- Prometheus metrics and OpenTelemetry trace propagation out of the box
- Fault injection endpoints for simulating errors, delays, and panics
- Helm chart with support for HPA, PDB, service accounts, and ingress
- Multi-architecture container images published to GitHub Container Registry

## Comparison with Similar Tools
- **httpbin** — Generic HTTP testing tool; Podinfo is purpose-built for Kubernetes platform validation
- **Nginx** — Static web server; Podinfo includes dynamic APIs, metrics, and chaos endpoints
- **Emojivoto** — Linkerd demo app; Podinfo is framework-agnostic and used across CNCF projects
- **Online Boutique** — Google's multi-service demo; Podinfo is a single-service reference for GitOps
- **Bookinfo** — Istio's demo; Podinfo is lighter and designed for progressive delivery testing

## FAQ
**Q: Is Podinfo meant for production workloads?**
A: Podinfo is primarily a reference and testing tool for Kubernetes platforms. Teams use it to validate their CI/CD pipelines, GitOps workflows, and service mesh configurations.

**Q: Which GitOps tools use Podinfo as their demo app?**
A: Flux CD, Flagger, Argo CD tutorials, and numerous CNCF project examples reference Podinfo for hands-on demonstrations.

**Q: Can I extend Podinfo with my own endpoints?**
A: Yes. The Go source is clean and modular, making it straightforward to add custom handlers or middleware.

**Q: Does Podinfo support gRPC?**
A: Yes. Podinfo runs both HTTP and gRPC servers simultaneously, configurable via separate port flags.

## Sources
- https://github.com/stefanprodan/podinfo
- https://github.com/stefanprodan/podinfo#readme

---
Source: https://tokrepo.com/en/workflows/asset-f5a1de1f
Author: Script Depot