Marker is the easiest way to match and mark strings for colorful terminal outputs.

marker

Marker is built for easily match and mark strings for colorful terminal outputs. You can match your strings with built-in matchers or easily implement a custom matcher for your usecase. Marker uses fatih/color for colorizing terminal output.

Installation

go get github.com/cyucelen/marker

Basic Usage

Marker has very simple and extensible way to get your strings colorful and brilliant!

Matchers

MatchAll

  aristotleQuote := "The more you know, the more you realize you don't know."
  emphasized := marker.Mark(aristotleQuote, marker.MatchAll("know"), color.New(color.FgRed))
  fmt.Println(emphasized)

MatchN

  boringLog := "[INFO] Nobody wants to read pale [INFO] tags."
  brilliantLog := marker.Mark(boringLog, marker.MatchN("[INFO]", 1), color.New(color.FgBlue))
  fmt.Println(brilliantLog)

MatchRegexp

  rhyme := "I scream, you all scream, we all scream for ice cream."
  r, _ := regexp.Compile("([a-z]?cream)")
  careAboutCream := marker.Mark(rhyme, marker.MatchRegexp(r), color.New(color.FgYellow))
  fmt.Println(careAboutCream)

Builder way

If you want to mark different patterns in the same string, marker builder is neater way to do this.

  rhyme := "I scream, you all scream, we all scream for ice cream."
  b := &marker.MarkBuilder{}
  r, _ := regexp.Compile("([a-z]?cream)")

  markedWithBuilder := b.SetString(rhyme).
    Mark(marker.MatchN("for ice", 1), color.New(color.FgRed)).
    Mark(marker.MatchAll("all"), color.New(color.FgMagenta)).
    Mark(marker.MatchRegexp(r), color.New(color.FgYellow)).
    Build()

  fmt.Println(markedWithBuilder)

Writing your custom Matcher

As you see in above examples, Mark function takes an MatcherFunc to match the patterns in given string and colorize them. A Matcher is a simple closure that returns a MatcherFunc to be called by Mark function to get Match information to put colorized versions of patterns into template.

Lets write our own custom Matcher that matches first encounter of given pattern.

Example

  func MatchFirst(pattern string) marker.MatcherFunc {
    return func(str string) marker.Match {
      return marker.Match{
        // replace first matching pattern with %s
        Template: strings.Replace(str, pattern, "%s", 1),
        // patterns to be colorized by Mark, in order 
        Patterns: []string{pattern},
      }
    }
  }

You can also check built-in markers for inspiration.

Contribution

I would like to accept any contributions to make Marker better and feature rich. So feel free to contribute your features(i.e. more Matchers!), improvements and fixes.

marco-silveira / marker