Health Actuator

A Spring Boot Actuator-like health monitoring library for Node.js. Automatically detects database and Redis connections and provides health check endpoints with zero configuration.

Features

- 🏥 Auto-Detection - Automatically detects MongoDB, PostgreSQL, MySQL, Prisma, Sequelize, and Redis connections
- 📊 Health Checks - Aggregate health status from all detected services
- 📈 Metrics - System and application metrics
- ℹ️ Info - Application information, environment variables, and system details
- 🔍 Liveness & Readiness - Kubernetes-ready probes

Installation

``bash
npm install @akshat001/health-actuator
`

Quick Start (Zero Configuration!)

`typescript
import express from 'express';
import { useHealthActuator } from '@akshat001/health-actuator';

const app = express();

// That's it! Auto-detects DB and Redis, all endpoints available
useHealthActuator(app);

app.listen(3000);
`

Endpoints automatically available:
- GET /health - Full health check (shows DB, Redis status)
- GET /health/liveness - Liveness probe
- GET /health/readiness - Readiness probe
- GET /info - Application info + environment variables
- GET /metrics - System metrics

Auto-Detection

The library automatically detects:

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- MongoDB (mongoose) - Detects mongoose.connection
- PostgreSQL (pg) - Detects global.pgPool
- MySQL (mysql2) - Detects global.mysqlPool
- Prisma - Detects PrismaClient instances
- Sequelize - Detects global.sequelize

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- ioredis - Auto-detects ioredis clients
- node-redis - Detects global.redisClient

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If auto-detection doesn't find your connections, register them manually:

`typescript
import express from 'express';
import {
useHealthActuator,
registerPostgres,
registerRedis
} from '@akshat001/health-actuator';
import { Pool } from 'pg';
import { createClient } from 'redis';

const app = express();

// Your database setup
const dbPool = new Pool({ / config / });
const redisClient = createClient({ / config / });

// Register connections (optional - auto-detection works for most cases)
registerPostgres(dbPool);
registerRedis(redisClient);

// Setup health actuator
useHealthActuator(app);

app.listen(3000);
`

Example Responses

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`json
{
"status": "UP",
"components": {
"mongodb": {
"status": "UP",
"details": { "message": "Database connection is healthy" }
},
"ioredis": {
"status": "UP",
"details": { "message": "Redis connection is healthy", "ping": "PONG" }
}
},
"timestamp": "2024-01-22T09:00:00.000Z"
}
`

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`json
{
"app": {
"name": "my-app",
"version": "1.0.0",
"node": "v20.0.0"
},
"system": {
"platform": "linux",
"arch": "x64",
"hostname": "server-01",
"cpus": 4,
"totalMemory": 8589934592,
"freeMemory": 4294967296
},
"environment": {
"NODE_ENV": "production",
"PORT": "3000",
"DATABASE_URL": "*",
"REDIS_URL": "*"
}
}
`

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`json
{
"uptime": {
"name": "uptime",
"value": 3600,
"unit": "seconds"
},
"memory": {
"heap": {
"used": { "name": "memory.heap.used", "value": 1048576, "unit": "bytes" },
"total": { "name": "memory.heap.total", "value": 2097152, "unit": "bytes" }
}
},
"cpu": {
"user": { "name": "cpu.user", "value": 123456, "unit": "microseconds" }
}
}
`

Complete Example

`typescript
// src/app.ts
import express from 'express';
import mongoose from 'mongoose';
import { useHealthActuator } from '@akshat001/health-actuator';

const app = express();

// Your database connection (mongoose will be auto-detected)
mongoose.connect('mongodb://localhost:27017/mydb');

// Your Redis connection (if using ioredis, will be auto-detected)
// const redis = new Redis('redis://localhost:6379');

// Setup health actuator - auto-detects mongoose and redis!
useHealthActuator(app);

// Your routes
app.get('/', (req, res) => {
res.json({ message: 'Hello World' });
});

app.listen(3000, () => {
console.log('Server running on http://localhost:3000');
console.log('Health: http://localhost:3000/health');
console.log('Info: http://localhost:3000/info');
console.log('Metrics: http://localhost:3000/metrics');
});
`

Custom Configuration (Optional)

`typescript
import express from 'express';
import { useHealthActuator, CustomIndicator } from '@akshat001/health-actuator';

const app = express();

useHealthActuator(app, {
basePath: '/actuator', // Custom base path
customIndicators: [
new CustomIndicator('external-api', async () => {
const response = await fetch('https://api.example.com/health');
return {
status: response.ok ? 'UP' : 'DOWN',
details: { statusCode: response.status }
};
})
]
});

app.listen(3000);
`

Environment Variables

You can configure via environment variables:

`bash
HEALTH_ACTUATOR_BASE_PATH=/actuator
HEALTH_ACTUATOR_ENABLE_HEALTH=true
HEALTH_ACTUATOR_ENABLE_METRICS=true
`

`typescript
import { useHealthActuator, loadConfigFromEnv } from '@akshat001/health-actuator';

useHealthActuator(app, loadConfigFromEnv());
``

License

MIT