SUSE/saptune

package system

import (
    "fmt"
    "io"
    "io/ioutil"
    "log"
    "os"
    "time"
)

var saptuneLogDir = "/var/log/saptune"
var infoLogger *log.Logger    // Info logger
var noticeLogger *log.Logger  // Notice logger
var debugLogger *log.Logger   // Debug logger
var errorLogger *log.Logger   // Error logger
var warningLogger *log.Logger // Warning logger
var verboseSwitch string      // Switch verbose mode on or off
var errorSwitch string        // Switch error mode on or off
var severDebugFormat = "DEBUG    "
var severNoticeFormat = "NOTICE   "
var severInfoFormat = "INFO     "
var severWarnFormat = "WARNING  "
var severErrorFormat = "ERROR    "
var logpidFormat = fmt.Sprintf("saptune[%v] ", os.Getpid()) // format to add pid of current saptune process to the log message
var debugSwitch = os.Getenv("SAPTUNE_DEBUG")                // Switch Debug on or off

// define log format
func logTimeFormat() string {
    return time.Now().Format("2006-01-02 15:04:05.000 ")
}

// DebugLog sends text to the debugLogger and stderr
func DebugLog(txt string, stuff ...interface{}) {
    if debugSwitch == "on" {
        if debugLogger != nil {
            debugLogger.SetPrefix(logTimeFormat() + severDebugFormat + logpidFormat)
            debugLogger.Printf(CalledFrom()+txt+"\n", stuff...)
        }
        fmt.Fprintf(os.Stderr, "DEBUG: "+txt+"\n", stuff...)
    }
}

// NoticeLog sends text to the noticeLogger and stdout
func NoticeLog(txt string, stuff ...interface{}) {
    if noticeLogger != nil {
        noticeLogger.SetPrefix(logTimeFormat() + severNoticeFormat + logpidFormat)
        noticeLogger.Printf(CalledFrom()+txt+"\n", stuff...)
        jWriteMsg("NOTICE", fmt.Sprintf(CalledFrom()+txt+"\n", stuff...))
        if verboseSwitch == "on" {
            fmt.Fprintf(os.Stdout, "NOTICE: "+txt+"\n", stuff...)
        }
    }
}

// InfoLog sends text only to the infoLogger
func InfoLog(txt string, stuff ...interface{}) {
    if infoLogger != nil {
        infoLogger.SetPrefix(logTimeFormat() + severInfoFormat + logpidFormat)
        infoLogger.Printf(CalledFrom()+txt+"\n", stuff...)
    }
}

// WarningLog sends text to the warningLogger and stderr
func WarningLog(txt string, stuff ...interface{}) {
    if warningLogger != nil {
        warningLogger.SetPrefix(logTimeFormat() + severWarnFormat + logpidFormat)
        warningLogger.Printf(CalledFrom()+txt+"\n", stuff...)
        jWriteMsg("WARNING", fmt.Sprintf(CalledFrom()+txt+"\n", stuff...))
        if verboseSwitch == "on" {
            fmt.Fprintf(os.Stderr, "WARNING: "+txt+"\n", stuff...)
        }
    }
}

// ErrLog sends text only to the errorLogger
func ErrLog(txt string, stuff ...interface{}) {
    if errorLogger != nil {
        errorLogger.SetPrefix(logTimeFormat() + severErrorFormat + logpidFormat)
        errorLogger.Printf(CalledFrom()+txt+"\n", stuff...)
        jWriteMsg("ERROR", fmt.Sprintf(CalledFrom()+txt+"\n", stuff...))
    }
}

// ErrorLog sends text to the errorLogger and stderr
func ErrorLog(txt string, stuff ...interface{}) error {
    if errorLogger != nil {
        errorLogger.SetPrefix(logTimeFormat() + severErrorFormat + logpidFormat)
        errorLogger.Printf(CalledFrom()+txt+"\n", stuff...)
        jWriteMsg("ERROR", fmt.Sprintf(CalledFrom()+txt+"\n", stuff...))
        if errorSwitch == "on" {
            fmt.Fprintf(os.Stderr, "ERROR: "+txt+"\n", stuff...)
        }
    }
    return fmt.Errorf(txt+"\n", stuff...)
}

// LogInit initialise the different log writer saptune will use
func LogInit(logFile string, logSwitch map[string]string) {
    var saptuneLog io.Writer

    if _, err := os.Stat(saptuneLogDir); err != nil {
        if err = os.MkdirAll(saptuneLogDir, 0755); err != nil {
            ErrorExit("", err)
        }
    }
    //create log file with desired read/write permissions
    saptuneLog, err := os.OpenFile(logFile, os.O_CREATE|os.O_APPEND|os.O_RDWR, 0644)
    if err != nil {
        ErrorExit("", err)
    }

    debugLogger = log.New(saptuneLog, "", 0)
    noticeLogger = log.New(saptuneLog, "", 0)
    infoLogger = log.New(saptuneLog, "", 0)
    warningLogger = log.New(saptuneLog, "", 0)
    errorLogger = log.New(saptuneLog, "", 0)

    debugSwitch = logSwitch["debug"]
    verboseSwitch = logSwitch["verbose"]
    errorSwitch = logSwitch["error"]
}

// SwitchOffLogging disables logging
func SwitchOffLogging() {
    debugSwitch = "off"
    verboseSwitch = "off"
    errorSwitch = "off"
    log.SetOutput(ioutil.Discard)
}