clr-installer/log/log.go

// Copyright © 2020 Intel Corporation
//
// SPDX-License-Identifier: GPL-3.0-only

package log

import (
	"fmt"
	"io"
	"log"
	"os"
	"path/filepath"
	"strings"

	"github.com/clearlinux/clr-installer/conf"
	"github.com/clearlinux/clr-installer/errors"
	"github.com/clearlinux/clr-installer/utils"
)

const (
	// LogLevelError specified the log level as: ERROR
	LogLevelError = 1

	// LogLevelWarning specified the log level as: WARNING
	LogLevelWarning = 2

	// LogLevelInfo specified the log level as: INFO
	LogLevelInfo = 3

	// LogLevelDebug specified the log level as: DEBUG
	LogLevelDebug = 4

	// LogLevelVerbose specified the log level as: VERBOSE
	// This is the same as Debug, but without the repeat filtering
	LogLevelVerbose = 5

	// configFilePreInstalPrefix is the prefix to create a configuration// file name
	configFilePreInstalPrefix = "pre-install-"
)

var (
	level      = LogLevelInfo
	levelMap   = map[int]string{}
	filehandle *os.File

	logFileName string
	preConfName string

	lineLast  string
	lineCount int
)

func init() {
	levelMap[LogLevelError] = "LogLevelError"
	levelMap[LogLevelWarning] = "LogLevelWarning"
	levelMap[LogLevelInfo] = "LogLevelInfo"
	levelMap[LogLevelDebug] = "LogLevelDebug"
	levelMap[LogLevelVerbose] = "LogLevelVerbose"
}

// SetLogLevel sets the default log level to l
func SetLogLevel(l int) {
	if l < LogLevelError {
		level = LogLevelError
		logTag("WRN", "Log Level '%d' too low, forcing to %s (%d)", l, levelMap[level], level)
	} else if l > LogLevelVerbose {
		level = LogLevelVerbose
		logTag("WRN", "Log Level '%d' too high, forcing to %s (%d)", l, levelMap[level], level)
	} else {
		level = l
		Debug("Log Level set to %s (%d)", levelMap[level], l)
	}
}

// SetOutputFilename ... sets the default log output to filename instead of stdout/stderr
func SetOutputFilename(logFile string) (*os.File, error) {
	logFileName = logFile
	var err error
	filehandle, err = os.OpenFile(logFile, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0644)
	if err != nil {
		return nil, err
	}

	log.SetOutput(filehandle)

	preConfName = filepath.Join(filepath.Dir(logFileName), configFilePreInstalPrefix+conf.ConfigFile)

	return filehandle, nil
}

// GetCrashInfoMsg returns the crash info message.
func GetCrashInfoMsg() string {
	msg := utils.Locale.Get("Please report this crash using %s", "GitHub Issues:")
	msg += "\n" + "https://github.com/clearlinux/clr-installer/issues"
	msg += "\n\n" + utils.Locale.Get("Include the following as attachments to enable diagnosis:")
	msg += "\n" + preConfName
	msg += "\n" + logFileName
	msg += "\n\n" + utils.Locale.Get("You may need to remove any personal data of concern from the attachments.")
	msg += "\n" + utils.Locale.Get("The Installer will now exit.")

	return msg
}

// RequestCrashInfo prints information for the user on how to properly report the
// crash of the installer and how to gather more information
func RequestCrashInfo() {
	fmt.Println(GetCrashInfoMsg())
}

// GetLogFileName ... returns the filename of the current log
func GetLogFileName() string {
	return logFileName
}

// GetPreConfFile ... returns the filename of where to store the pre-configuration file
func GetPreConfFile() string {
	return preConfName
}

// ArchiveLogFile copies the contents of the log to the given filename
func ArchiveLogFile(archiveFile string) error {
	if filehandle == nil {
		return errors.Errorf("Log output should be set, see log.SetOutputFilename()")
	}

	a, err := os.OpenFile(archiveFile, os.O_RDWR|os.O_CREATE, 0644)
	if err != nil {
		return err
	}

	defer func() {
		_ = a.Close()

		// Jump back to the end of the log file
		_, _ = filehandle.Seek(0, 2)
	}()

	_ = filehandle.Sync()

	// Jump to the beginning of the file
	_, err = filehandle.Seek(0, 0)
	if err != nil {
		Error("Failed to seek log file (%v)", err)
	}

	var bytesCopied int64
	bytesCopied, err = io.Copy(a, filehandle)
	if err != nil {
		Error("Failed to archive log file (%v) %q", err, archiveFile)
	}
	Debug("Archived %d bytes to file %q", bytesCopied, archiveFile)
	_ = a.Sync()

	return err
}

// LevelStr converts level to its text equivalent, if level is invalid
// an error is returned
func LevelStr(level int) (string, error) {
	for k, v := range levelMap {
		if k == level {
			return v, nil
		}
	}

	return "", fmt.Errorf("Invalid log level: %d", level)
}

func logTag(tag string, format string, a ...interface{}) {
	// If there are no variable to pass to the format,
	// then we can escape any % signs.
	if len(a) < 1 {
		format = strings.ReplaceAll(format, "%", "%%")
	}

	f := "[" + tag + "] " + format + "\n"
	output := fmt.Sprintf(f, a...)

	if level >= LogLevelVerbose {
		log.Print(output)
		return
	}

	if output != lineLast {
		// output the previous repeated line
		if lineCount > 0 {
			plural := ""
			if lineCount > 1 {
				plural = "s"
			}

			repeat := fmt.Sprintf("[%s] [Previous line repeated %d time%s]\n", tag, lineCount, plural)
			log.Print(repeat)
		}

		log.Print(output)

		lineLast = output
		lineCount = 0
	} else { // Repeated line
		lineCount++
	}
}

// Debug prints a debug log entry with DBG tag
func Debug(format string, a ...interface{}) {
	if level < LogLevelDebug {
		return
	}

	logTag("DBG", format, a...)
}

// Error prints an error log entry with ERR tag
func Error(format string, a ...interface{}) {
	logTag("ERR", format, a...)
}

// ErrorError prints an error log entry with ERR tag, it takes an
// error instead of format and args, if a TraceableError is provided
// then we also include the trace information in the error message
func ErrorError(err error) {
	msg := err.Error()

	if e, ok := err.(errors.TraceableError); ok {
		msg = fmt.Sprintf("%s %s", e.Trace, e.What)
	}

	logTag("ERR", msg)
}

// Info prints an info log entry with INF tag
func Info(format string, a ...interface{}) {
	if level < LogLevelInfo {
		return
	}

	logTag("INF", format, a...)
}

// Warning prints an warning log entry with WRN tag
func Warning(format string, a ...interface{}) {
	if level < LogLevelWarning {
		return
	}

	logTag("WRN", format, a...)
}