Golang : How to validate ISBN?

This tutorial will show you an example on how to validate ISBN with the govalidator package and then get the book information from http://www.isbnsearch.org/. The HTML data dump will not be parsed, but you can extract the relevant information you want easily. See this tutorial on how to extract links from web page to get the idea on how to extract the book title and prices.

NOTE : There are two versions of ISBN(International Standard Book Number) standard. The ISBN is 13 digits long if assigned on or after 1 January 2007, and 10 digits long if assigned before 2007.

Here you go!

 package main

 import (
 "fmt"
 "github.com/asaskevich/govalidator"
 "io/ioutil"
 "net/http"
 "os"
 "strings"
 )

 func main() {

 isbn := "0-201-53377-4" // before 2007 - 10 digits
 // see https://en.wikipedia.org/wiki/International_Standard_Book_Number

 validISBN := govalidator.IsISBN(isbn, 10) //use version 10

 // can use govalidator.IsISBN10 or IsISBN13 as well.
 fmt.Printf("%s is a valid ISBN : %v \n", isbn, validISBN)

 if validISBN {
 // remove all dashes
 noDashISBN := strings.Replace(isbn, "-", "", -1)

 resp, err := http.Get("http://www.isbnsearch.org/isbn/" + noDashISBN)

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 defer resp.Body.Close()

 htmlData, err := ioutil.ReadAll(resp.Body)

 if err != nil {
 fmt.Println(err)
 os.Exit(1)
 }

 fmt.Println(os.Stdout, string(htmlData))

 // see https://www.socketloop.com/tutorials/golang-how-to-extract-links-from-web-page
 // on how to scrape the information you want from HTML
 }
 }

Happy coding!

References :

https://en.wikipedia.org/wiki/InternationalStandardBook_Number