Darpan 🪞

दर्पण (Darpan) = Mirror in Hindi/Sanskrit
Your development environment, reflected in real-time

Zero-config service monitoring for Linux developers. Auto-discovers and monitors databases, APIs, Docker containers, and caches with real-time health checks, live log streaming, network activity tracking, and extensible service packs.

cargo install darpan
darpan watch  # That's it!

✨ What You Get

Before Darpan 😓

$ systemctl status postgresql redis nginx
$ docker ps | grep mongo
$ lsof -i :3000,5432,6379
$ curl localhost:8000/health
$ journalctl -u postgresql -f
$ tail -f /var/log/nginx/error.log

6 commands. 6 terminal tabs. Constant context switching.

With Darpan ✨

$ darpan watch

┌─ Darpan - myproject | Live Monitor ─────────────────┐
│ STATUS    │ NAME        │ TYPE      │ PORT  │ CONN  │
├───────────┼─────────────┼───────────┼───────┼───────┤
│ ✓ Healthy │ PostgreSQL  │ Database  │  5432 │ 3     │
│ ✓ Healthy │ Redis       │ Cache     │  6379 │ 0     │
│ ✓ Healthy │ Frontend    │ HTTP      │  3000 │ 1     │  ← Works without /health!
│ ✗ Down    │ API Server  │ HTTP      │  8000 │ -     │
└──────────────────────────────────────────────────────┘
3/4 healthy | Enter: details | L: logs | r: refresh

One command. One dashboard. Everything.

🚀 Key Features

🔍 Zero-Config Auto-Discovery

• Instant detection: PostgreSQL, Redis, MySQL, MongoDB, Docker, HTTP servers
• Multi-source scanning: Ports, processes, Docker API, systemd units
• Smart recognition: Service signatures and common patterns
• Extensible: Service packs for custom stacks (Node.js, Django, etc.)
• Just works: No setup required

💚 Intelligent Health Monitoring

• Multi-tier checks: HTTP endpoints → Port connectivity → Process verification
• Database pings: PostgreSQL, Redis, MySQL, MongoDB
• Traffic-based: Frontend/Backend services use network activity (no HTTP spam)
• Script support: Custom health checks via commands
• Fallback logic: Services without /health work (React, Vue, Angular dev servers)

📡 Live Network Activity Tracking ⚡ NEW

═══ Network Activity ═══
Port Status: LISTENING ✓
Active Connections: 5 (traffic detected)
Process Connections: 3 established, 1 listening

• See actual traffic to your services
• Detect hung connections or leaks
• Verify listening status even without health endpoints
• Process-level insights for deep debugging

🔍 Real-Time Log Streaming

┌─ SERVICE LOGS: Redis ─────────────────────────┐
│ [12:30:45 INFO ] Starting Redis 7.0.15        │
│ [12:30:46 INFO ] Ready to accept connections  │
│ [12:30:50 WARN ] Memory usage: 2.1MB          │
└───────────────────────────────────────────────┘
Press /: search | 1-4: filter level | E: export

Auto-detects log sources:

• 🐳 Docker: stdout/stderr from containers
• ⚙️ Systemd: journalctl integration
• 📁 Files: /var/log/, ./logs/, ~/.pm2/logs/
• ⚡ Process: Direct stdout/stderr capture
• 🔧 Scripts: Custom commands (e.g., journalctl -u {systemd_unit} -f)

Interactive features:

• Search (/), filter (1-4), pause (Space), scroll (↑↓, mouse wheel)
• Copy selection (v/y/Ctrl+C), export (E)
• Page navigation (PageUp/PageDown, g/G, Home/End)

🎨 Beautiful TUI

• Keyboard-driven (Vim-style j/k support)
• Color-coded status indicators
• Live auto-refresh
• Service details with diagnostics
• Network activity section

📦 Installation

# From crates.io (recommended)
cargo install darpan

# From source
git clone https://github.com/codeBunny2022/darpan.git
cd darpan
cargo install --path .

# Verify
darpan --version  # v0.2.5+

Requirements: Rust 1.70+, Linux
Optional: Docker, systemd, ss/netstat

🎯 Quick Start

Basic Commands

darpan watch              # Interactive TUI (recommended)
darpan status             # Quick CLI status
darpan why "Redis"        # Troubleshoot specific service
darpan status --format json  # For scripts/CI
darpan init               # Create .darpan.yml template

TUI Navigation

Log Viewer (Press L)

📚 Configuration (Optional)

Darpan works without config. Add .darpan.yml for custom services:

version: 1
services:
  - name: My API
    type: http_server
    port: 8000
    health_check:
      type: http
      path: /api/health
    log_file: /var/log/myapi/app.log
  - name: PostgreSQL
    type: { database: postgres }
    port: 5432
    health_check:
      type: postgres

Locations: ./.darpan.yml (project) or ~/.config/darpan/config.yml (user)

🌟 Examples

Microservices: Auto-detect Docker containers, APIs, databases
Debugging: Press L → search logs → export for analysis
CI/CD: darpan status --format json | jq '.[] | select(.status != "Healthy")'

🔌 Extensibility ⚡ NEW

Extend Darpan without code changes:

Service Packs (YAML)

Share detection rules, health checks, and log paths for common stacks:

# ~/.config/darpan/packs/my-stack.yml
name: my-stack
version: "1.0.0"
signatures:
  - name: My API
    type: http_server
    role: backend
    port: 8080
    process_pattern: "my-api"
    health_check:
      type: http
      path: /health

Packs auto-load from:

• ~/.config/darpan/packs/*.yml (user-wide)
• .darpan.d/packs/*.yml (project-local)

Script-Based Checks

Custom health checks and log sources via commands:

health_check:
  type: custom
  script: "curl -f http://{host}:{port}/health || exit 1"

log_paths:
  - "journalctl -u {systemd_unit} -f"

Placeholders: {name}, {host}, {port}, {pid}, {systemd_unit}

Programmatic extensions also supported. See Extensibility Guide and example packs.

🔧 Troubleshooting

Service not detected? → Check port (ss -tln) or add to .darpan.yml (darpan init)
Logs not showing? → Check permissions or specify log_file in config
Health check wrong? → Override health_check in .darpan.yml

🤝 Contributing

Contributions welcome! Please see CONTRIBUTING.md for:

• Code of conduct
• Development setup
• Pull request process
• Testing guidelines

📄 License

MIT License - see LICENSE for details.

Created by Chirag (chiraglabs)

🙏 Acknowledgments

Built with:

• Ratatui - Terminal UI
• Tokio - Async runtime
• Bollard - Docker API
• Serde - Serialization

Inspired by tools like htop, docker-compose, and systemctl status.

💬 Support

• Issues: GitHub Issues
• Discussions: GitHub Discussions
• Crates.io: crates.io/crates/darpan

⭐ Star this repo if Darpan helps you!

Made with ❤️ by developers, for developers.