deadslog

A dead simple logger module for Node.js. Provides console and file-based logging with support for log rotation, custom formatting, colored output, and robust error handling.

✨ Features

• 🖥 Console and file logging
• 🔄 Log rotation with delete/archive strategies
• 🧩 Customizable log formatting
• 🌈 Colored log levels in console
• 🧱 Handles undefined/non-serializable messages
• 🧠 TypeScript type definitions included
• 🔁 ESM + CommonJS support

📦 Installation

npm install deadslog
# or
bun add deadslog

🚀 Usage

🔹 Basic

import deadslog from "deadslog";
const logger = deadslog();
logger.info("Hello, world!");

🎨 With Custom Formatter

const logger = deadslog({
  formatter: (level, message) => {
    const timestamp = new Date().toLocaleString();
    return `---\nTime: ${timestamp}\nLevel: ${level}\nMessage: ${message}\n---`;
  },
});
logger.info("Custom formatted log!");

📁 File Logging & Rotation

const logger = deadslog({
  fileOutput: {
    enabled: true,
    logFilePath: "./logs/app.log",
    rotate: true,
    maxLogSize: 1024 * 1024, // 1MB
    maxLogFiles: 3,
    onMaxLogFilesReached: "archiveOld", // or "deleteOld"
  },
});
logger.info("This will be written to a file!");

📦 CommonJS Usage

const deadslog = require("deadslog");
const logger = deadslog();
logger.info("Hello from CJS!");

📘 API

deadslog(config)

Returns a logger instance.

⚙️ Configuration Options

| Option | Type | Description | | --------------------------------- | ---------- | -------------------------------------------------------------------------------- | | consoleOutput.enabled | boolean | Enable console logging (default: true) | | consoleOutput.coloredCoding | boolean | Enable colored output using chalk (default: true) | | fileOutput.enabled | boolean | Enable file logging (default: false) | | fileOutput.logFilePath | string | File path for log output (required if file logging is enabled) | | fileOutput.rotate | boolean | Enable automatic log file rotation | | fileOutput.maxLogSize | number | Maximum log file size in bytes before rotation | | fileOutput.maxLogFiles | number | Number of rotated files to keep | | fileOutput.onMaxLogFilesReached | string | Rotation strategy: "deleteOld" or "archiveOld" | | formatter | function | Optional custom formatter for log messages | | minLevel | string | Minimum log level: trace, debug, info, success, warn, error, fatal | | filters.include | string | Word filter to include from log | | filters.exclude | string | Word filter to exclude from log |

🧰 Logger Methods

• trace(msg)
• debug(msg)
• info(msg)
• success(msg)
• warn(msg)
• error(msg)
• fatal(msg)
• flush()
• destroy()

🧠 TypeScript

Type definitions are included and will be picked up automatically.

📚 Formatter Examples For Use

🧾 1. Simple Timestamp Formatter

const simpleFormatter = (level, message) => {
  const timestamp = new Date().toISOString();
  return `[${timestamp}] [${level}] ${message}`;
};

[2025-05-03T13:45:21.123Z] [INFO] Application started

📜 2. Multiline Developer-Friendly Formatter

const multilineFormatter = (level, message) => {
  const timestamp = new Date().toLocaleString();
  return `---\nTime: ${timestamp}\nLevel: ${level}\nMessage: ${message}\n---`;
};

---
Time: 5/3/2025, 1:46:11 PM
Level: DEBUG
Message: Connected to database
---

📁 3. File-Friendly CSV Formatter

const csvFormatter = (level, message) => {
  const timestamp = new Date().toISOString();
  const escaped = message.replace(/"/g, '""');
  return `"${timestamp}","${level}","${escaped}"`;
};

"2025-05-03T13:47:02.789Z","ERROR","Failed to load module: ""auth.js"""

🌈 4. Emoji-Coded Formatter

const emojiFormatter = (level, message) => {
  const emojis = {
    trace: '🔍',
    debug: '🐛',
    info: 'ℹ️',
    success: '✅',
    warn: '⚠️',
    error: '❌',
    fatal: '💀'
  };
  const timestamp = new Date().toISOString();
  return `${emojis[level] || ''} [${timestamp}] ${level}: ${message}`;
};

✅ [2025-05-03T13:48:15.456Z] SUCCESS: Task completed

🪵 5. JSONL (JSON Lines) Formatter for Parsing

const jsonlFormatter = (level, message) => {
  return JSON.stringify({
    ts: Date.now(),
    level,
    message
  });
};

{"ts":1714740493123,"level":"INFO","message":"Something happened"}

Changelog

[v1.2.2] - 2025-05-24

Fixed

• Types file was not included in the package, causing issues for TypeScript users.

See CHANGELOG.md for previous versions and more details.

License

MIT