Hellog

Your new logger!

hellog is a general-purpose logging library.

It offers a console.log-like API and formatting, plugin-based extensibility, all that with 0 dependencies.

Installation

npm install @steffthestunt/hellog

Usage

Import hellog into your project and start logging:

import Hellog from '@steffthestunt/hellog';

// Initialize with default config
const logger = new Hellog();

logger.debug('Hello, world!');
// Outputs : 2024-12-21T13:48:08.064Z [INFO] Hello, world!

logger.info('This is an info message.');
// Outputs : 2024-12-21T13:48:08.064Z [INFO] This is an info message.

logger.warn('This is a warning message.');
// Outputs : 2024-12-21T13:48:08.064Z [WARN] This is a warning message.

logger.error('This is an error message.');
// Outputs : 2024-12-21T13:48:08.064Z [ERROR] This is an error message.

logger.info('Logging a number:', 123);
// Outputs : 2024-12-21T13:48:08.064Z [INFO] Logging a number: 123

logger.info('Logging an object:', { key: 'value' });
// Outputs : 2024-12-21T13:48:08.064Z [INFO] Logging an object: { key: 'value' }

logger.info('Logging an array:', [1, 2, 3]);
// Outputs : 2024-12-21T13:48:08.064Z [INFO] Logging an array: [ 1, 2, 3 ]

Features

• Console-like API: Use debug, info, warn, and error methods.
• Plugin-based extensibility: Extend functionality with plugins.
• Zero dependencies: Lightweight and easy to integrate.

Plugins

Hellog's plugin system allows you to extend its functionality. Plugins can modify log messages and control how they are output.

Default Plugins

Hellog comes with these plugins enabled by default:

• HellogLineBreakDefaultPlugin - A plugin to split console.log messages that would span over multiple lines and format each line separately.
• HellogPrettyDefaultPlugin - A plugin to format log messages in a more readable way: {timestamp} [{level}] {message}.
• HellogStdoutDefaultPlugin - A plugin to output log messages to stdout or stderr depending on the level.

Creating a Plugin

Plugins are created by extending the HellogPlugin base class:

import { HellogPlugin } from '@steffthestunt/hellog';

class TimestampPlugin extends HellogPlugin {
  transform(message, level) {
    const timestamp = new Date().toISOString();
    return `[${timestamp}] ${message}`;
  }
}

// Initialize logger with custom plugins
const logger = new Hellog({
  plugins: [new TimestampPlugin()],
});

Plugin Examples

Common plugin configurations:

import {
  HellogLineBreakPlugin,
  HellogPrettyPlugin,
  HellogStdoutPlugin,
} from '@steffthestunt/hellog';

// Initialize with multiple plugins
const logger = new Hellog({
  plugins: [
    // Default plugins
    new HellogLineBreakPlugin(),
    new HellogPrettyPlugin(),
    new HellogStdoutPlugin(),

    // Custom plugins
    new TimestampPlugin(),
  ],
});