Writing logs to a file in Go using a buffer (Go version 1.19)

logging.go

package logging

import (
	"fmt"
	"os"
	"time"
)

var enable_logging bool = true

const LOGS_BUFFER_SIZE = 50

var logs_buffer []string = make([]string, 0, LOGS_BUFFER_SIZE)

func Print(a ...any) {
	if (enable_logging == false) {
		return
	}
	fmt.Print(a...)
	addStringToLogsBuffer(fmt.Sprint(a...))
}

func Printf(format string, a ...any) {
	if (enable_logging == false) {
		return
	}
	fmt.Printf(format, a...)
	addStringToLogsBuffer(fmt.Sprintf(format, a...))
}

func Println(a ...any) {
	if (enable_logging == false) {
		return
	}
	fmt.Println(a...)
	addStringToLogsBuffer(fmt.Sprintln(a...))
}

func addStringToLogsBuffer(logString string) {

	currentTimeMillis := time.Now()
	timeString := fmt.Sprint(currentTimeMillis.Format("Mon Jan 2 15:04:05"))

	index := len(logs_buffer)
	if (index < cap(logs_buffer)) {
		logs_buffer = append(logs_buffer, timeString + ": \t" + logString)
	}

	if (index == LOGS_BUFFER_SIZE - 1) {

		fmt.Println("Logs buffer is full...")

		//Buffer is full, write logs to logs file and clear the buffer.
		for _, logInBuffer := range logs_buffer {
			logsWriter := createLogsFile()
			if (logsWriter == nil) {
				return
			}
			defer logsWriter.Close()
			fmt.Fprint(logsWriter, logInBuffer)
			logs_buffer = make([]string, 0, LOGS_BUFFER_SIZE)
		}
	}
}

func createLogsFile() *os.File {

	//Create logs folder
	os.Mkdir("logs", 0755)

	f, err := os.OpenFile("logs/logs", os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0644)
	if err != nil {
        fmt.Println("Something went wrong while creating logs/logs file: ", err.Error())
		return nil
    }
	return f
}

Not synchronized and therefore not suitable for use by multiple threads at once!