logger_en.md

Logger Package (pkg/logger)

The logger package provides a lightweight and high-performance logging tool tailored for HypGo. Built on Go's standard library log, it extends functionality with colored output, multi-level filtering, and automatic log rotation.

Key Features

• Multiple Log Levels: Supports DEBUG, INFO, NOTICE, WARN, ERROR, EMERGENCY levels for easy output granularity control.
• Automatic Log Rotation: Built-in LogRotator that can automatically split log files based on file size or retention days and clean up old logs, preventing disk exhaustion.
• Readable Colored Terminal Output: When logging to stdout/stderr, color highlighting of levels and alignment is automatically enabled, greatly improving the development experience.
• Key-Value Logging Support: Provides convenient syntax for printing parameter variables, which are automatically formatted and appended to log messages.
• Global Instance (Singleton) and Flexible Configuration: Provides InitLogger and GetLogger for a convenient global logger integration.

Basic Usage

Use GetLogger() to get the global Logger for logging anywhere:

package main

import (
    "github.com/maoxiaoyue/hypgo/pkg/logger"
)

func main() {
    log := logger.GetLogger()
    
    // Set output level (all levels at or above DEBUG will be output)
    log.SetLevel(logger.DEBUG)

    // Basic log output
    log.Info("Server started")
    
    // Output with variables
    log.Debug("New connection request received", "client_ip", "192.168.1.100", "port", 8080)
    
    // Error occurred
    log.Error("Unable to write to database: %v", err)
    
    // Fatal error, exits with os.Exit(1) after output
    log.Fatal("Core system component missing!")
}

Log Rotation and File Output

If you want to save logs to a file instead of the terminal, configure the output path and expiry mechanism:

log := logger.GetLogger()

// Set log output to logs/app.log file
log.SetFile("logs/app.log")

// Set automatic rotation strategy
log.SetRotator(&logger.LogRotator{
    filename:   "logs/app.log", // Same path as SetFile output
    maxSize:    10485760,        // Maximum file size (10 MB)
    maxAge:     7,               // Keep logs for this many days
    maxBackups: 5,               // Maximum number of historical log files to keep
})