Logger Package

A lightweight and versatile logger for structured and consistent logging in Node.js and browser environments. Includes human-readable timestamps and supports multiple log levels.

Features

• Human-Readable Timestamps: Logs include precise timestamps for better traceability.
• Flexible Log Levels: Supports info, warn, and error log levels.
• Environment-Based Control: Adjusts logging behavior for development and production environments.

Installation

Install the package via npm:

npm install reactjs-logger

Usage

Importing the Logger

import log from "reactjs-logger";

Logging Examples

1. Log with Explicit Level

log("info", "This is an informational message.");
log("warn", "This is a warning message.", { usage: "85%" });
log("error", "An error occurred!", new Error("Sample error"));

2. Log with Default Level (info)

If the log level is omitted, the default is info:

log("Task completed successfully.", { taskId: 123 });

API Documentation

log(level: LogLevel | unknown, ...messages: unknown[]): void

Logs messages with a specified log level. If no valid log level is provided, the function defaults to info.

Parameters

• level: (LogLevel | unknown)
  The log level ("info", "warn", or "error"). If this doesn't match a valid log level, it is treated as part of the message.

• ...messages: (unknown[])
  The messages to log. Can include strings, objects, or any data type.

Example

log("info", "Application started.");
log("warn", "High memory usage detected.", { usage: "95%" });
log("error", "Unhandled exception occurred.", new Error("Sample error"));

Log Levels

| Level | Description | Example Usage | | ------- | -------------------------------- | ------------------------------------- | | info | General informational messages. | log("info", "Server started."); | | warn | Warnings about potential issues. | log("warn", "Disk usage high."); | | error | Errors or critical issues. | log("error", "Failed to connect."); |

Environment Configuration

Control logging behavior using environment variables:

• NEXT_PUBLIC_LOGGER: Enables or disables logging. Set to true to enable logging.
• NODE_ENV: Adjusts log level filtering based on the environment.
  • development: Logs all levels (info, warn, error).
  • production: Logs only warn and error levels.

Example .env File

NEXT_PUBLIC_LOGGER=true
NODE_ENV=production

Production Considerations

1. Minimize Logs: In production, only log necessary levels (warn and error) to avoid performance degradation.
2. Use Centralized Logging: Route logs to tools like AWS CloudWatch, Datadog, or Logstash for better observability.
3. Avoid Sensitive Data: Ensure no sensitive information (like API keys or passwords) is logged.