Node-Error-Logger.js

A lightweight, zero-dependency logger for Node.js with file logging, error stacks, and console-style usage.

This package is designed for developers who want simple, predictable logging without pulling in large logging frameworks.

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✨ Features

• ✅ Zero dependencies
• ✅ Supports info, warn, and error levels
• ✅ Console-style logging (multiple arguments like console.log)
• ✅ Automatic error stack trace logging
• ✅ Logs stored by date and level
• ✅ Optional JSON logs (production-friendly)
• ✅ Optional size-based log rotation
• ✅ Async, non-blocking file writes
• ✅ Backward compatible across all v1.x versions

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📦 Installation

npm i node-error-logger.js

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🚀 Basic Usage (Backward Compatible)

const Logger = require('node-error-logger.js');

Logger.info('Application started');
Logger.warn('Low memory warning');
Logger.error('Something went wrong');

This works exactly the same as earlier versions.

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🧩 Multiple Arguments (Console-style)

Just like console.log, you can pass multiple values:

Logger.info('User created', userId, userData);
Logger.warn('Invalid input', { field: 'email' });

Extra values are treated as metadata.

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❌ Error Object Support (Automatic)

Pass an Error anywhere in the arguments:

try {
  throw new Error('Database connection failed');
} catch (err) {
  Logger.error('Unhandled exception', err, { retry: false });
}

✔ Logs the error message ✔ Logs the full stack trace ✔ No extra configuration required

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📂 Log Output Structure

Logs are written to the application root:

logs/
 ├── info/
 │   └── 2025-01-01-info.log
 ├── warn/
 │   └── 2025-01-01-warn.log
 └── error/
     └── 2025-01-01-error.log

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🧪 JSON Logging Mode (Optional)

Ideal for production environments and log processors.

const Logger = require('node-error-logger.js');

const logger = Logger.createLogger({ json: true });

logger.error('Payment failed', new Error('timeout'), { orderId: 123 });

Example JSON Output

{
  "timestamp": "2025-01-01T12:00:00.000Z",
  "level": "error",
  "message": "Payment failed",
  "meta": [{ "orderId": 123 }],
  "error": {
    "name": "Error",
    "message": "timeout",
    "stack": "..."
  }
}

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🔁 Log Rotation (Optional)

Enable size-based log rotation to prevent large log files.

const logger = Logger.createLogger({
  rotate: true,
  maxSizeMB: 10
});

• Rotation is disabled by default
• Old files are renamed with a timestamp

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🛠 API Reference

Logger.info(...args)

Logs informational messages.

Logger.warn(...args)

Logs warnings.

Logger.error(...args)

Logs errors and automatically captures stack traces when an Error is provided.

Logger.createLogger(options)

Creates a new logger instance with custom options.

Options

Option	Type	Default	Description
json	boolean	false	Enable JSON log output
rotate	boolean	false	Enable size-based log rotation
maxSizeMB	number	5	Max log file size before rotation

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🔒 Backward Compatibility Guarantee

All existing usage patterns are fully supported in all v1.x releases.

New features are:

• optional
• opt-in
• non-breaking

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❗ What This Package Is (and Is Not)

✅ This package is:

• Simple
• Lightweight
• Predictable
• Ideal for small services, scripts, and APIs

❌ This package is NOT:

• A replacement for Winston or Pino.
• A plugin-based logging framework.
• Designed for massive distributed systems.

If you need advanced transports or integrations, a full-featured logger may be a better fit.

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📄 License

MIT © Mohammad Moiz Ali (MAKSTYLE119)