Nyx

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Nyx is a GoLang demo application designed for validating Kubernetes controllers, Prometheus metrics, and modern cloud-native best practices. It provides a simple HTTP API and exposes Prometheus metrics, making it ideal for testing, learning, and integration with Kubernetes monitoring stacks.

Features

• HTTP API: Simple endpoints for demo and health checks.
• Prometheus Metrics: Exposes HTTP request counters and histograms for monitoring.
• Kubernetes Native: Includes manifests for deployment, service, and ServiceMonitor.
• Configurable: Supports configuration via YAML file, environment variables, and command-line flags.
• Graceful Shutdown: Handles SIGINT/SIGTERM for clean exits.

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Getting Started

Prerequisites

• Go 1.24+
• Docker (optional, for container builds)
• Kubernetes cluster (for deployment)
• Prometheus Operator (for ServiceMonitor support)

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Running Locally

1. Clone the repository

   git clone https://github.com/MatteoMori/nyx.git
   cd nyx

2. Build and run

   go build -o nyx
   ./nyx start

3. Access the API

   • HTTP server: http://localhost:8080/hello
   • Metrics: http://localhost:9090/metrics

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Configuration

Nyx supports configuration via:

• YAML file (nyx.yaml)
• Environment variables
• Command-line flags

Example nyx.yaml:

prometheusPort: "9090"
verbosity: 1

Environment variable override:

export PROMETHEUSPORT=12345
./nyx start

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Kubernetes Deployment

1. Apply the manifests

   kubectl apply -f manifests/

2. Expose metrics to Prometheus

   kubectl apply -f manifests/servicemonitor.yaml

3. Access the app

   • HTTP: via the nyx service on port 80
   • Metrics: via the nyx-metrics service on port 9090

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Metrics

Nyx exposes the following Prometheus metrics:

• http_requests_total{path,method,status}: Total number of HTTP requests.
• http_request_duration_seconds{path,method}: Histogram of request durations.

Metrics are available at /metrics on the configured Prometheus port (default: 9090).

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Project Structure

.
├── cmd/                # CLI entrypoints (Cobra)
├── manifests/          # Kubernetes manifests
├── pkg/
│   ├── nyx/            # Application logic and metrics
│   └── shared/         # Shared config types
├── main.go             # Main entrypoint
├── nyx.yaml            # Example config
├── Dockerfile          # Multi-stage build for container images
└── README.md           # This file