logify-log-js

A simple and customizable logging utility for Node.js, allowing you to log messages with different levels (info, warn, error, debug) to both the console and a log file. The log messages are formatted with a timestamp for better readability.

Installation

To install the package via npm, run the following command:

npm install logify-log-js

Usage

1. Basic Usage (Log to Console and File)

To use the logger in your project, simply import the logger instance and use it to log messages.

import { logger } from 'logify-log-js';

logger.log('info', 'This is an informational message');
logger.log('warn', 'This is a warning message');
logger.log('error', 'This is an error message');
logger.log('debug', 'This is a debug message');

2. Log Levels

This logger supports four log levels: info, warn, error, and debug. Each log level is displayed with a different color in the console for better distinction.

• info: Blue color in console, logged to the file.
• warn: Yellow color in console, logged to the file.
• error: Red color in console, logged to the file.
• debug: Green color in console, logged to the file.

logger.log('info', 'Informational message');
logger.log('warn', 'Warning message');
logger.log('error', 'Error message');
logger.log('debug', 'Debug message');

3. Custom Log File

By default, the logger writes to a file named logs.txt. You can specify your own log file name when initializing the Logger class.

import { logger } from 'logify-log-js';

const customLogger = new Logger('custom-log.txt');
customLogger.log('info', 'This message will be logged to custom-log.txt');

4. File Log Format

Each log message written to the file will include a timestamp and the log level in the format:

[YYYY-MM-DDTHH:mm:ss.sssZ] [LEVEL] Your message here

Example:

[2025-02-09T12:00:00.000Z] [INFO] This is an info message
[2025-02-09T12:01:00.000Z] [ERROR] This is an error message

Methods

log(level: string, message: string)

Logs a message with a specified log level (info, warn, error, debug). The message will be logged both to the console (with color) and to the log file.

Example usage:

logger.log('info', 'Informational message');
logger.log('warn', 'Warning message');
logger.log('error', 'Error message');
logger.log('debug', 'Debug message');

writeToFile(message: string)

Writes a message to the log file.

formatMessage(level: string, message: string)

Formats the log message with a timestamp and the log level.

License

This project is licensed under the MIT License.

Author

Le Minh Hieu