Golang : Create unique title slugs example

A simple example on how to create title slug from a string and also demonstrate what you can do in case the title slug is not unique after querying the database. In this example, we append the number from 1 to 10 in case there's a conflict of title slugs in the database. The range of numbers from 1 to 10 should be sufficient. Feel free to increase to 100 to ensure there are more rooms to generate unique title slugs.

Here you go!

 package main

 import (
 "fmt"
 "golang.org/x/text/transform"
 "golang.org/x/text/unicode/norm"
 "regexp"
 "strconv"
 "strings"
 "unicode"
 )

 func isMn(r rune) bool {
 return unicode.Is(unicode.Mn, r) // Mn: nonspacing marks
 }

 func stringToSlug(s string) (string, error) {
 str := []byte(strings.ToLower(s))

 // convert all spaces to dash
 regE := regexp.MustCompile("[[:space:]]")
 str = regE.ReplaceAll(str, []byte("-"))

 // remove all blanks such as tab
 regE = regexp.MustCompile("[[:blank:]]")
 str = regE.ReplaceAll(str, []byte(""))

 // remove all punctuations with the exception of dash

 regE = regexp.MustCompile("[!/:-@[-`{-~]")
 str = regE.ReplaceAll(str, []byte(""))

 regE = regexp.MustCompile("/[^\x20-\x7F]/")
 str = regE.ReplaceAll(str, []byte(""))

 regE = regexp.MustCompile("`&(amp;)?#?[a-z0-9]+;`i")
 str = regE.ReplaceAll(str, []byte("-"))

 regE = regexp.MustCompile("`&([a-z])(acute|uml|circ|grave|ring|cedil|slash|tilde|caron|lig|quot|rsquo);`i")
 str = regE.ReplaceAll(str, []byte("\\1"))

 regE = regexp.MustCompile("`[^a-z0-9]`i")
 str = regE.ReplaceAll(str, []byte("-"))

 regE = regexp.MustCompile("`[-]+`")
 str = regE.ReplaceAll(str, []byte("-"))

 strReplaced := strings.Replace(string(str), "&", "", -1)
 strReplaced = strings.Replace(strReplaced, `"`, "", -1)
 strReplaced = strings.Replace(strReplaced, "&", "-", -1)
 strReplaced = strings.Replace(strReplaced, "--", "-", -1)

 if strings.HasPrefix(strReplaced, "-") || strings.HasPrefix(strReplaced, "--") {
 strReplaced = strings.TrimPrefix(strReplaced, "-")
 strReplaced = strings.TrimPrefix(strReplaced, "--")
 }

 if strings.HasSuffix(strReplaced, "-") || strings.HasSuffix(strReplaced, "--") {
 strReplaced = strings.TrimSuffix(strReplaced, "-")
 strReplaced = strings.TrimSuffix(strReplaced, "--")
 }

 // normalize unicode strings and remove all diacritical/accents marks
 // see https://www.socketloop.com/tutorials/golang-normalize-unicode-strings-for-comparison-purpose

 t := transform.Chain(norm.NFD, transform.RemoveFunc(isMn), norm.NFC)
 slug, _, err := transform.String(t, strReplaced)

 if err != nil {
 return "", err
 }

 return strings.TrimSpace(slug), nil
 }

 func main() {
 testStr := "?This is a test-title with question mark ? and& \" exclaimation mark !"
 testSlug, err := stringToSlug(testStr)
 if err != nil {
 panic(err)
 }
 fmt.Printf("%v to:\n %v\n", testStr, testSlug)

 // in case you encounter a situation where the slug title is not unique after you query the database.
 // just append a number the string with a number to make it unique
 // NOTE : You will have to make a function of your own here to query your database

 newSlug := ""

 for i := 1; i <= 10; i++ {
 newSlug = testSlug + "-" + strconv.Itoa(i)
 // here is where you want to query your database
 // if newSlug is unique, break

 // let's pretend that number 5 is unique after querying
 // the database 5 times.
 if i == 5 {
 break
 }
 }

 // our unique slug title
 fmt.Println(newSlug)

 }

Output:

?This is a test-title with question mark ? and& " exclaimation mark ! to:

this-is-a-test-title-with-question-mark-and-exclaimation-mark

this-is-a-test-title-with-question-mark-and-exclaimation-mark-5

NOTE: Before inserting the title slugs into your database, it would be advisable to trim the title first.

References:

https://www.socketloop.com/tutorials/golang-format-strings-to-seo-friendly-url-example

https://www.socketloop.com/tutorials/golang-increment-string-example