game-library-infra

Infrastructure services for game-library application. Includes distributed tracing, log management, and metrics collection.

Services

Service	Description
Zipkin	Distributed tracing system
Jaeger	Distributed tracing system with native OTLP support
Graylog	Log management platform (with MongoDB and OpenSearch)
Prometheus	Metrics collection and monitoring

Quick Start with Docker

# Start all services
make all

# Or start individual services
make zipkin
make jaeger
make prometheus
make graylog

# Stop all services
make stop

# Stop and remove volumes
make clean

Access URLs and Credentials

Service	URL	Credentials
Zipkin	http://localhost:9411/zipkin	No authentication required
Jaeger	http://localhost:16686	No authentication required
Prometheus	http://localhost:9090	No authentication required
Graylog	http://localhost:9000	admin:admin
OpenSearch	http://localhost:9200	No authentication (security disabled)

Graylog Setup

After starting Graylog, you need to create a GELF input to receive logs:

1. Open Graylog at http://localhost:9000 and log in with admin/admin
2. Go to System → Inputs
3. Select GELF UDP from the dropdown and click Launch new input
4. Configure the input:
   • Global: Check this box
   • Title: GELF UDP
   • Bind address: 0.0.0.0
   • Port: 12201
5. Click Launch and complete the setup wizard

The input will now accept GELF messages on UDP port 12201.

Example Application

The example/ folder contains a sample Go application demonstrating integration with all infrastructure services.

Features

• Distributed tracing - OpenTelemetry with Zipkin exporter and OTLP exporter (Jaeger)
• Graylog logging - zap logger with GELF output
• Prometheus metrics - request counters, error counters, response duration histograms
• Connected traces - HTTP client and server spans are linked via trace propagation

Endpoints

Endpoint	Description
GET /api/data	Returns in 10-100ms (random delay)
GET /api/slow	Returns in 200-1000ms (random delay), 10% error rate
GET /metrics	Prometheus metrics
GET /health	Health check

Running the Example

# Start infrastructure services first
make all

# Run the example app
make run-example

Project Structure

game-library-infra/
├── .github/workflows/
│   └── main.yml          # CI/CD pipeline
├── .k8s/
│   ├── namespace.yaml    # Kubernetes namespace
│   ├── cert.yaml         # Let's Encrypt ClusterIssuers (HTTP-01 & DNS-01)
│   ├── secrets.yaml      # Secrets for MongoDB, Graylog, Cloudflare
│   ├── graylog.yaml      # Graylog deployment
│   ├── mongo.yaml        # MongoDB deployment
│   ├── opensearch.yaml   # OpenSearch deployment
│   ├── jaeger.yaml       # Jaeger deployment
│   ├── prometheus.yaml   # Prometheus deployment
│   └── zipkin.yaml       # Zipkin deployment (deprecated)
├── example/
│   ├── main.go           # Application entry point
│   ├── logger.go         # Zap + Graylog logger setup
│   ├── tracer.go         # OpenTelemetry tracer setup (Zipkin + OTLP exporters)
│   ├── metrics.go        # Prometheus metrics middleware
│   ├── handlers.go       # HTTP handlers
│   ├── client.go         # HTTP client with tracing + load generator
│   ├── go.mod
│   └── go.sum
├── docker-compose.yml    # Local development setup
├── Makefile              # Build and run commands