Enlog

An enchanted logging library for GO. It supports colored output and writing to .log files.

Install

Simple go get it into your project:

go get github.com/malekim/enlog

Log types

Info

Info log shows messages in green color by default. Prefix is set to "INFO" by default. UseFile is set to false by default. FilePath is set to "info.log" by default.

Usage

You can use methods: Info() and Infof()

l := enlog.New()
l.Info("Test info")
msg := "Test message"
l.Infof("Test message: %s", message)

Example of info log

INFO: 2020/06/17 09:15:55 info.go:16: info

Debug

Debug log shows messages in cyan color by default. Prefix is set to "DEBUG" by default. UseFile is set to false by default. FilePath is set to "debug.log" by default.

Usage

You can use methods: Debug() and Debugf()

l := enlog.New()
l.Debug("Test debug")
msg := "Test message"
l.Debugf("Test message: %s", message)

Example of debug log

DEBUG: 2020/06/17 09:15:55 debug.go:17: debug

Error

Error log shows messages in red color by default. Prefix is set to "ERROR" by default. UseFile is set to false by default. FilePath is set to "error.log" by default.

Usage

l := enlog.New()
l.Error("Test error")
msg := "Test message"
l.Errorf("Test message: %s", message)

Example of error log

ERROR: 2020/06/17 09:15:55 error.go:17: error

Trace

Trace log shows messages in magenta color by default. Prefix is set to "TRACE" by default. UseFile is set to false by default. FilePath is set to "trace.log" by default.

Usage

l := enlog.New()
l.Trace("Test trace")
msg := "Test message"
l.Tracef("Test message: %s", message)

Example of trace log

TRACE: 2020/06/17 09:15:55 trace.go:17: trace

Event after log

The event is called after every log. You can set it up like this:

l := enlog.New()
l.SetAfterLogEvent(func(logType string, message string) {
  fmt.Printf("Type: %s, message %s", logType, message)
})

Customization

Fields of enlog which contains settings of particular log types are:

• InfoLog for log type info
• DebugLog for log type debug
• ErrorLog for log type error
• TraceLog for log type trace

l := enlog.New()
infoLog := l.InfoLog
debugLog := l.DebugLog
errorLog := l.ErrorLog
traceLog := l.TraceLog

Examples use InfoLog, but each of those log types are customizable in the same way.

Prefix

l := enlog.New()
l.InfoLog.SetPrefix("NEW")
l.InfoLog.GetPrefx() // returns string NEW
l.Info("Test message")

Example:

NEW: 2020/06/17 09:15:55 info.go:16: Test message

File logs

By default logs are not saved to files. To change it you need to switch "useFile" parameter. If error occurs during creating or opening the file, "useFile" automatically switches back to false.

l := enlog.New()
l.InfoLog.GetUseFile() // returns false
l.InfoLog.SetUseFile(true)
l.InfoLog.GetUseFile() // returns true
l.Info("Test message") // log shown in terminal and saved to info.log
l.InfoLog.GetFilePath() // returns "info.log"
l.InfoLog.SetFilePath("new.log")
l.InfoLog.GetFilePath() // returns "new.log"
l.Info("Test message") // log shown in terminal and saved to new.log

Single file log

Sometimes it is necessary to save all log messages to single file. It is possible to set one file log for all log types.

var l *Enlog = New()
newFilePath := "single.log"
l.InfoLog.SetFilePath(newFilePath)
l.DebugLog.SetFilePath(newFilePath)
l.TraceLog.SetFilePath(newFilePath)
l.ErrorLog.SetFilePath(newFilePath)
l.InfoLog.SetUseFile(true)
l.DebugLog.SetUseFile(true)
l.TraceLog.SetUseFile(true)
l.ErrorLog.SetUseFile(true)

l.Info("Info log is saved to single.log")
l.Debug("Debug log is saved to single.log")
l.Error("Error log is saved to single.log")
l.Trace("Trace log is saved to single.log")

Setting filePath before useFile prevents enlog from creating default .log files.

Colors

To change default color you need to modify "color" parameter (uint8).

l := enlog.New()
l.InfoLog.GetColor() // returns 32
l.InfoLog.SetColor(enlog.ColorRed)
l.InfoLog.GetColor() // returns 31

Road map

Road map for future releases:

• custom date and time format of logs
• chunk log files

Running tests

go test -gcflags=-l -coverprofile=coverage.txt -covermode=atomic ./... &&  go tool cover -html=coverage.txt

Note that flag -gcflags=-l is necessary for bou.ke/monkey library.