allgreen 0.1.0

Simple, beautiful health checks for Python applications

✅ Allgreen - Python Health Checks Made Simple

Add quick, simple, and beautiful health checks to your Python application via a /healthcheck endpoint.

Perfect for monitoring application health, smoke testing, and ensuring your services are running properly in production.

🚀 Features

• 🎯 Simple DSL - Define health checks in intuitive, readable Python
• 🌐 Beautiful Web Dashboard - Responsive UI with automatic dark mode
• ⚡ Fast & Lightweight - Minimal dependencies, maximum performance
• ⏰ Timeout Protection - Prevent hanging checks with configurable timeouts
• 🔄 Rate Limiting - Control expensive operations ("2 times per hour")
• 🌍 Environment Conditions - Run checks only in specific environments
• 💾 Result Caching - Cache expensive operations between rate-limited runs
• 📊 Multiple Output Formats - HTML dashboard, JSON API, or both
• 🔧 Framework Agnostic - Works with Flask, Django, FastAPI, or standalone

📦 Installation

pip install allgreen

🎯 Quick Start

1. Create your health checks

Create an allgood.py file in your project root:

# allgood.py

@check("Database connection is healthy")
def database_check():
    # Your database connection logic
    make_sure(db.is_connected(), "Database should be accessible")

@check("API response time is acceptable")
def api_performance_check():
    response_time = api.ping()
    expect(response_time).to_be_less_than(200)  # milliseconds

@check("Disk space is sufficient") 
def disk_space_check():
    usage_percent = get_disk_usage()
    expect(usage_percent).to_be_less_than(90)

2. Add to your web application

Flask:

from flask import Flask
from allgreen import mount_healthcheck

app = Flask(__name__)
mount_healthcheck(app, app_name="My API")

Django: Add to urls.py

from allgreen import create_app
from django.urls import path, include

healthcheck_app = create_app(app_name="My Django App")
urlpatterns = [
    path('healthcheck/', include(healthcheck_app)),
]

Standalone:

from allgreen import run_standalone
run_standalone(app_name="My Service", port=8080)

3. View your dashboard

Visit /healthcheck in your browser to see a beautiful dashboard, or add ?format=json for machine-readable output.

📚 Complete DSL Reference

Basic Assertions

@check("Basic truthiness check")
def basic_check():
    make_sure(True, "Custom failure message")
    make_sure(user.is_authenticated())

Expectation Methods

@check("Mathematical expectations")
def math_check():
    expect(2 + 2).to_eq(4)
    expect(api.response_time()).to_be_less_than(100)
    expect(database.connection_count()).to_be_greater_than(0)

⏰ Advanced Features

Timeout Protection

@check("Slow external service", timeout=30)  # 30 seconds max
def external_service_check():
    # This check will be terminated if it takes longer than 30 seconds
    response = external_api.health_check()
    make_sure(response.ok)

Rate Limiting for Expensive Operations

@check("Expensive API call", run="2 times per hour", timeout=60)
def expensive_check():
    # This check only runs twice per hour, caching results between runs
    result = paid_api.run_diagnostics()
    expect(result.status).to_eq("healthy")

@check("Daily backup verification", run="1 time per day")
def daily_backup_check():
    # Perfect for expensive operations that should only run occasionally
    backup_status = verify_backup_integrity()
    make_sure(backup_status.valid)

Supported rate limiting patterns:

• "1 time per minute"
• "5 times per hour"
• "2 times per day"

Environment-Specific Checks

@check("Production database performance", only="production")
def prod_db_check():
    # Only runs in production environment
    expect(db.query_time()).to_be_less_than(10)

@check("Development tools available", except_env=["production", "staging"])
def dev_tools_check():
    # Skipped in production and staging
    make_sure(debug_tools.available())

@check("Conditional feature check", if_condition=lambda: feature_flag.enabled())
def feature_check():
    # Only runs when condition is true
    expect(new_feature.status()).to_eq("operational")

🌐 Web Interface

HTML Dashboard

Visit /healthcheck for a beautiful, responsive dashboard featuring:

• ✅ Color-coded check results (pass/fail/skip)
• 🌙 Automatic dark mode based on system preferences
• ⏱️ Execution timing for each check
• 📊 Summary statistics
• 📱 Mobile-responsive design

JSON API

Access /healthcheck.json or /healthcheck?format=json for machine-readable output:

{
  "status": "passed",
  "environment": "production", 
  "stats": {
    "total": 8,
    "passed": 6,
    "failed": 1,
    "skipped": 1
  },
  "checks": [
    {
      "description": "Database connection",
      "status": "passed",
      "duration_ms": 23.4
    }
  ]
}

HTTP Status Codes

• 200 OK - All checks passing
• 503 Service Unavailable - One or more checks failing

Perfect for integration with monitoring tools like:

• UptimeRobot
• Pingdom
• Datadog
• Custom monitoring solutions

🔧 Framework Integration

Flask Application

from flask import Flask
from allgreen import mount_healthcheck

app = Flask(__name__)

# Mount health checks
mount_healthcheck(
    app, 
    app_name="My Flask API",
    config_path="config/allgood.py",
    environment="production"
)

if __name__ == '__main__':
    app.run()

Django Integration

# health/urls.py
from allgreen import create_app

healthcheck_app = create_app(
    app_name="My Django App",
    config_path="myapp/health_checks.py"
)

# main/urls.py  
urlpatterns = [
    path('health/', include('health.urls')),
]

FastAPI Integration

from fastapi import FastAPI
from allgreen import create_app

app = FastAPI()
healthcheck_app = create_app(app_name="My FastAPI")

app.mount("/health", healthcheck_app)

Standalone Server

from allgreen import run_standalone

if __name__ == "__main__":
    run_standalone(
        app_name="Health Check Service",
        config_path="checks/allgood.py", 
        host="0.0.0.0",
        port=8080,
        environment="production"
    )

📁 Examples

Check out the examples/ directory for complete working examples:

• examples/allgood.py - Basic health checks
• examples/advanced_allgood.py - Advanced features (timeouts, rate limiting)

🧪 Configuration File Locations

Allgreen automatically looks for configuration files in these locations:

1. allgood.py (project root)
2. config/allgood.py
3. Custom path via config_path parameter

🎛️ Environment Variables

• ENVIRONMENT - Sets the environment for conditional checks (default: "development")

📊 Best Practices

✅ Good Health Check Examples

@check("Database queries are fast")
def db_performance():
    start = time.time()
    users = User.objects.all()[:10] 
    duration = (time.time() - start) * 1000
    expect(duration).to_be_less_than(100)  # under 100ms

@check("External API is responsive")  
def api_health():
    response = requests.get("https://api.example.com/health", timeout=5)
    expect(response.status_code).to_eq(200)
    
@check("Cache is working", run="5 times per hour")
def cache_check():
    cache.set('test_key', 'test_value')
    expect(cache.get('test_key')).to_eq('test_value')

❌ What to Avoid

• Don't make checks that modify data
• Avoid checks that depend on external timing
• Don't put business logic in health checks
• Avoid checks that could cause cascading failures

🔒 Security Notes

• Health check endpoints don't require authentication by default
• Consider restricting access in production environments
• Avoid exposing sensitive system information in check descriptions
• Rate limiting helps prevent abuse of expensive operations

🛠️ Development

git clone https://github.com/navinpai/allgreen
cd allgreen
uv venv
source .venv/bin/activate
uv pip install -e ".[dev]"

# Run tests
python -m pytest

# Run linting  
ruff check .

# Start example server
python test_server.py

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Make your changes
4. Add tests for new functionality
5. Ensure all tests pass (python -m pytest)
6. Run linting (ruff check .)
7. Commit your changes (git commit -m 'Add amazing feature')
8. Push to the branch (git push origin feature/amazing-feature)
9. Open a Pull Request

📝 License

This project is licensed under the MIT License - see the LICENSE file for details.

🙏 Acknowledgments

• Inspired by the Allgood Ruby gem
• Built with ❤️ for the Python community