Golang : How to add color to string?

Back in the days of DOS ( before GUI was popular), programmers use colors to decorate text based application to enhance usage experience.

Those with in-depth knowledge of assembly language usually ended up creating their own Graphical User Interface components or use third party library. I still remember that I have to invoke the mouse cursor via the DOS interrupt 33 and provide the mouse cursor glyph. Anyway, this tutorial won't be touching on how to use GUI with Golang. (I write another tutorial for that one day), but will show you how to add color to your string.

There is a Golang package that allows you to add color to string easily and you can get it from https://github.com/mgutz/ansi

with go get -u github.com/mgutz/ansi

and once you have included the mgutz/ansi package...... the code to use them is pretty straightforward.

For example :

 package main

 import (
 "fmt"
 "github.com/mgutz/ansi"
 "time"
 )

 func main() {

 // style format :
 // "foregroundColor+attributes:backgroundColor+attributes"

 // For example : red blinking on white background
 ansi.Color("%v your text", "red+B:white")

 // colorize a string, SLOW
 msg := ansi.Color("foo", "red+b:white")
 fmt.Println(msg)

 msg2 := ansi.Color("foo", "yellow")
 fmt.Println(msg2)

 underlineRed := ansi.ColorFunc("red+u")
 fmt.Printf(underlineRed("text") + "\n")

 // add color to log output example

 cyan := ansi.ColorFunc("cyan+")
 fmt.Printf(cyan("%v ▶ debug ******* \n"), time.Now())

 magenta := ansi.ColorFunc("magenta+")
 fmt.Printf(magenta("%v ▶ info ******* \n"), time.Now())

 yellow := ansi.ColorFunc("yellow+")
 fmt.Printf(yellow("%v ▶ notification ******* \n"), time.Now())

 red := ansi.ColorFunc("red+")
 fmt.Printf(red("%v ▶ WARNING : Crashing soon! \n"), time.Now())

 // cache escape codes and build strings manually
 lime := ansi.ColorCode("green+h:black")
 reset := ansi.ColorCode("reset")

 fmt.Println(lime, "Bring back the 80s!", reset)
 }

For more color codes, please see the official documentation at https://github.com/mgutz/ansi

UPDATE : Do check out this package as well https://github.com/fatih/color

Reference :

https://github.com/mgutz/ansi