I am using Go. I want to create a log file called webapp.log when I run go run main.go.
However, when I run go run main.go, the message "2021/09/25 14:58:55 open : no such file or directory" appears in the terminal and the log file is not created.
I can't tell from the message which location is causing the log file not to be created. If anyone can help me, please let me know. main.go

package main

import (
    "fmt"
    "golang_todo_app/config"
    "log"
)

func main() {
  fmt.Println(config.Config.Port)
  fmt.Println(config.Config.SQLDriver)
  fmt.Println(config.Config.DbName)
  fmt.Println(config.Config.LogFile)
  log.Println("test")
}

config/config.go

package config

import (
    "golang_todo_app/utils"
    "log"

    "gopkg.in/go-ini/ini.v1"
)

type ConfigList struct {
    Port string
    SQLDriver string
    DbName string
    LogFile string
}

var Config ConfigList

func init () {
  LoadConfig()
  utils.LoggingSettings(Config.LogFile)
}

func LoadConfig() {
  cfg, err := ini.Load("config.ini")
  if err != nil {
    log.Fatalln()
  }
  Config = ConfigList{
    Port: cfg.Section("web").Key("port").MustString("8080"),
    SQLDriver: cfg.Section("db").Key("driver").String(),
    DbName: cfg.Section("db").Key("name").String(),
    LogFile: cfg.Section("web").Key("logfile").String(),
  }
}

utils/logging.go

package utils

import (
    "io"
    "log"
    "os"
)

func LoggingSettings(logFile string) {
  logfile, err := os.OpenFile(logFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
  if err != nil {
    log.Fatalln(err)
  }
  multiLogFile := io.MultiWriter(os.Stdout, logfile)
  log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
  log.SetOutput(multiLogFile)
}

CodePudding user response：

"2021/09/25 14:58:55 open : no such file or directory"

Have a look of your code, the most possible place which will raise this error is next:

logfile, err := os.OpenFile(logFile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)

Usually if we open a file with no permission e.g. /root/log.txt, it could produce next:

2021/09/25 17:50:07 open /root/log.txt: permission denied

You could see the /root/log.txt will be displayed to tell user which file can't be open, but for you, your error return nothing after open. This means for next code:

LoggingSettings(Config.LogFile)

The Config.LogFile parser returns nothing. The correct ini setting maybe next:

config.ini:

[web]
logfile=/tmp/log.txt

You should check your ini file to see if any mistake makes the code can't parse a valid logfile value.

BTW, next code will happen when you import "golang_todo_app/config", so your print in main function executed after next function, your print in main won't have chance to run if the error haapens in init.

func init () {
  LoadConfig()
  utils.LoggingSettings(Config.LogFile)
}