Ldap filter beautifier

example.go

package main

/*
Put ldap.go in ldap subdir
Run: go build example.go
Run: ./example < ldap-filter.txt 
*/

import (
  "fmt"
  "os"
  "bufio"
  "log"
  "bytes"
  "./ldap"
)

func main() {
    scanner := bufio.NewScanner(os.Stdin)
    var b bytes.Buffer
    for scanner.Scan() {
        b.WriteString(scanner.Text())
        b.WriteString("\n")
    }
    fmt.Printf(ldap.FormatFilter(b.String()))

    if err := scanner.Err(); err != nil {
        log.Println(err)
    }
}

ldap.go

package ldap

import (
	"strings"
)

// inspired by https://blogs.technet.microsoft.com/389thoughts/2016/11/24/ldap-query-prettyfier/
func FormatFilter(filter string) string {
	buffer := new(strings.Builder)

	noSpaces := strings.Replace(filter, " ", "", -1)
	noSpaces = strings.Replace(noSpaces, "\n", "", -1)

	tabLevel := 0
	tabString := "  "
	inline := false
	for _, char := range noSpaces {
		switch char {
		case '(':
			buffer.WriteString("\n")
			buffer.WriteString(strings.Repeat(tabString, tabLevel))
			buffer.WriteString("(")
			tabLevel = tabLevel + 1
			inline = false
		case ')':
			tabLevel = tabLevel - 1
			if !inline {
				buffer.WriteString(strings.Repeat(tabString, tabLevel))
			}
			buffer.WriteString(")\n")
			inline = false
		default:
			inline = true
			buffer.WriteRune(char)
		}
	}

	return buffer.String()
}