JB Logger

A high-performance, production-ready logging package for Go applications with automatic file rotation and structured logging capabilities. Built with focus on performance, reliability, and ease of use, this logger provides both file-based logging with automatic rotation and colored console output for development.

Key Features

• Automatic Log Rotation: Rotates logs when file size reaches 25MB (configurable)
• Organized Archive: Rotated logs are stored in numbered files (1.log, 2.log, etc.)
• Colored Console Output: Different colors for each log level
• Asynchronous Logging: High-performance non-blocking operations
• Buffered Channels: Configurable buffer size for optimal performance
• Stack Traces: Detailed stack traces for error debugging
• Thread-Safe: Safe for concurrent use
• Structured Format: Consistent, easy-to-parse log format

Installation

To install the latest version:

go get github.com/jbarasa/logger@latest

To install a specific version:

go get github.com/jbarasa/[email protected]

To update to the latest version in an existing project:

go get -u github.com/jbarasa/logger@latest

Usage

package main

import (
    "github.com/jbarasa/logger/logger"
    "errors"
)

func main() {
    // Initialize logger with configuration
    err := logger.Initialize(logger.Config{
        LogPath:     "storage/logs/app.log",
        MaxFileSize: 25 * 1024 * 1024,    // 25MB
        Level:       logger.DEBUG,         // Minimum log level
        BufferSize:  500000,              // Channel buffer size
        IsDev:       true,                // Enable console output with colors
    })
    if err != nil {
        panic(err)
    }
    defer logger.Close()

    // Example logging
    logger.Debug("Debug message: Starting application")
    logger.Info("Server started on port %d", 8080)
    logger.Warn("High memory usage: %d%%", 85)
    logger.Error("Failed to connect to database: %v", errors.New("connection timeout"))
    
    // Error with stack trace
    err = errors.New("critical database error")
    logger.ErrorWithStack("Database operation failed", err)
}

Log Format

Console Output (Development Mode)

2024/12/30 22:45:40 [DEBUG] [main.go:25] Debug message: Starting application
2024/12/30 22:45:40 [INFO]  [main.go:26] Server started on port 8080
2024/12/30 22:45:40 [WARN]  [main.go:27] High memory usage: 85%
2024/12/30 22:45:40 [ERROR] [main.go:28] Failed to connect to database: connection timeout

Log Colors (Console)

• DEBUG: Blue
• INFO: Green
• WARN: Yellow
• ERROR: Red
• FATAL: Purple

Configuration Options

• LogPath: Path for the log file (with extension)

  • Example: "storage/logs/app.log"
  • When rotated, old logs move to "storage/logs/archive/N.log"

• MaxFileSize: Maximum size of log file before rotation (in bytes)

  • Default: 25MB (25 * 1024 * 1024 bytes)
  • When reached, current log is moved to archive and new file is created

• Level: Minimum log level to record

  • Available levels: DEBUG, INFO, WARN, ERROR, FATAL
  • Messages below this level are ignored

• BufferSize: Size of the internal channel buffer for async logging

  • Default: 100000
  • Larger values can improve performance but use more memory

• IsDev: Development mode flag

  • When true: Enables colored console output
  • When false: Logs only to files

Log Rotation

Logs are automatically rotated when file size exceeds MaxFileSize. The rotation process:

1. Current log file (app.log) reaches size limit
2. File is moved to archive/1.log (or next available number)
3. New empty app.log is created
4. Logging continues to new file

Archive structure:

storage/
  └── logs/
      ├── app.log     (current log file)
      └── archive/
          ├── 1.log   (oldest)
          ├── 2.log
          └── 3.log   (newest)

Performance

The logger uses several techniques for optimal performance:

• Non-blocking log calls using buffered channels
• Batch writing to improve I/O performance
• Efficient file rotation with minimal locking
• Memory-efficient buffer management

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the Mozilla Public License Version 2.0 - see the LICENSE file for details.

Version History

• v1.0.2: (2024-12-30)

  • Simplified log rotation with archive directory
  • Fixed memory usage in file operations
  • Improved thread safety
  • Removed cleanup functionality in favor of simple rotation

• v1.0.1: Bug fixes and performance improvements

• v1.0.0: Initial release

  • Basic logging functionality
  • Multiple log levels
  • Async logging
  • Stack trace support