imskyer / errlog

Enhance Golang source code debugging with code highlight, failing func call recognition and pretty stack trace printing.

A simple package to enhance Go source code debugging

Introduction

Use errlog to enhance your error logging with :

• Code source highlight
• Failing func recognition
• Readable stack trace

Get started

Install

go get github.com/snwfdhmp/errlog

Import

import "github.com/snwfdhmp/errlog"

Usage

func someFunc() {
    //...
    if errlog.Debug(err) { // will debug & pass if err != nil, will ignore if err == nil
        return
    }
}

Example

We will use this sample program :

package main

import (
	"errors"
	"fmt"

	"github.com/snwfdhmp/errlog"
)

func main() {
	fmt.Println("Start of the program")

	wrapingFunc()

	fmt.Println("End of the program")
}

func wrapingFunc() {
	someBigFunction()
}

func someBigFunction() {
	someSmallFunction()

	if err := someNastyFunction(); errlog.Debug(err) {
		return
	}

	someSmallFunction()
}

func someSmallFunction() {
	fmt.Println("I do things !")
}

func someNastyFunction() error {
	return errors.New("I'm failing for no reason")
}

Output

Configure like you need

You can configure your own logger with these options :

type Config struct {
	PrintFunc          func(format string, data ...interface{}) //Printer func (eg: fmt.Printf)
	LinesBefore        int  					//How many lines to print *before* the error line when printing source code
	LinesAfter         int 						//How many lines to print *after* the error line when printing source code
	PrintStack         bool 					//Shall we print stack trace ? yes/no
	PrintSource        bool 					//Shall we print source code along ? yes/no
	PrintError         bool 					//Shall we print the error of Debug(err) ? yes/no
	ExitOnDebugSuccess bool 					//Shall we os.Exit(1) after Debug has finished logging everything ? (doesn't happen when err is nil)
}

Example

In this example, logrus is used, but any other logger can be used. PrintFunc is of type func (format string, data ...interface{}), so you can easily implement your own logger func. Beware that you should add '\n' at the end of format string when printing.

Now using a custom configuration.

debug := errlog.NewLogger(&errlog.Config{
	PrintFunc:          logrus.Printf,
	LinesBefore:        2,
	LinesAfter:         1,
	PrintError:         true,
	PrintSource:        true,
	PrintStack:         false,
	ExitOnDebugSuccess: true,
})

Output

Another Example

Errlog finds the exact line where the error is defined.

Output

Documentation

Documentation can be found here :

Feedback

Feel free to open an issue for any feedback or suggestion.

I fix process issues quickly.

Contributions

PR are accepted as soon as they follow Golang common standards. For more information: https://golang.org/doc/effective_go.html

License information