Golang终端字符串匹配与彩色标记插件库marker的使用

简介

Marker是一个用于在终端输出中匹配和标记字符串的Golang库，可以轻松实现彩色输出效果。它使用fatih/color库来实现终端输出的彩色化。

安装

go get github.com/cyucelen/marker

基本用法

简单示例

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)

标记日志流

你可以将marker与Golang的log包或任何支持io.Writer的接口集成。

stdoutMarker := marker.NewStdoutMarker()
markRules := []marker.MarkRule{
  {marker.MatchBracketSurrounded(), color.New(color.FgBlue)},
  {marker.MatchAll("marker"), color.New(color.FgRed)},
}

stdoutMarker.AddRules(markRules)
logger := log.New(stdoutMarker, "", 0)

logger.Println("[INFO] marker is working as expected")

自定义io.Writer输出

f, _ := os.Create("/tmp/awesome.log")
w := bufio.NewWriter(f)

writeMarker := marker.NewWriteMarker(w)

markRules := []marker.MarkRule{
  {marker.MatchBracketSurrounded(), blueFg},
  {marker.MatchAll("marker"), magentaFg},
}

writeMarker.AddRules(markRules)

logger := log.New(writeMarker, "", 0)
logger.Println("[INFO] colorful logs even in files, marker to mark them all!")

w.Flush()
f.Close()

output := catFile("/tmp/awesome.log") // $ cat /tmp/awesome.log
fmt.Print(output)

匹配器

MatchAll

匹配所有出现的指定字符串

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

匹配前N次出现的指定字符串

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

使用正则表达式匹配

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)

MatchSurrounded

匹配被特定字符包围的文本

sentence := "I pull out things surrounded by abcWHOA COLORSdef"
markedSurrounded := marker.Mark(sentence, marker.MatchSurrounded("abc", "def"), color.New(color.FgMagenta))
fmt.Println(markedSurrounded)

MatchBracketSurrounded

匹配被方括号包围的文本

sentence = "[INFO] This is what log lines look like"
markedSurrounded = marker.Mark(sentence, marker.MatchBracketSurrounded(), color.New(color.FgRed))
fmt.Println(markedSurrounded)

MatchParensSurrounded

匹配被圆括号包围的文本

sentence = "[ERROR] This is what (parens) lines look like"
markedSurrounded = marker.Mark(sentence, marker.MatchParensSurrounded(), color.New(color.FgBlue))
fmt.Println(markedSurrounded)

MatchTimestamp

匹配时间戳

goodOldTimes := "2006-01-02T15:04:05Z07:00 [INFO] Loading King of Fighters '97 ROM"
timestampMarked := marker.Mark(goodOldTimes, marker.MatchTimestamp(time.RFC3339), color.New(color.FgBlue))
fmt.Println(timestampMarked)

构建器模式

如果你想在同一字符串中标记不同的模式，可以使用构建器模式：

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)

自定义匹配器

你可以创建自己的匹配器：

func MatchFirst(pattern string) marker.MatcherFunc {
  return func(str string) marker.Match {
    return marker.Match{
      // 将第一个匹配的模式替换为%s
      Template: strings.Replace(str, pattern, "%s", 1),
      // 需要被Mark着色的模式，按顺序
      Patterns: []string{pattern},
    }
  }
}

贡献

欢迎任何贡献来使Marker更好、功能更丰富。可以贡献你的特性（如更多的匹配器）、改进和修复。