Read a XML file in Go




Golang has a very powerful encoding/xml package that comes with the standard library. All you need to do is the create the data structures to map according to XML document.

In this tutorial we will learn how to read this XML document with the xml.Unmarshal() function

Employee.xml

 <?xml version="1.0"?>
 <company>
 <staff>
 <id>101</id>
 <firstname>Derek</firstname>
 <lastname>Young</lastname>
 <username>derekyoung</username>
 </staff>
 <staff>
 <id>102</id>
 <firstname>John</firstname>
 <lastname>Smith</lastname>
 <username>johnsmith</username>
 </staff>
 </company>

and map to these data structs and print out the values

 type Staff struct {
 XMLName xml.Name `xml:"staff"`
 ID int `xml:"id"`
 FirstName string `xml:"firstname"`
 LastName string `xml:"lastname"`
 UserName string `xml:"username"`
 }

 type Company struct {
 XMLName xml.Name `xml:"company"`
 Staffs []Staff  `xml:"staff"`
 }

In real life, a company has many staffs. Therefore, we map Company.Staffs to Staff struct.

With the data structures defined. We are going to use the xml.Unmarshal() function to load the XML data into the Company structure.

 var c Company
 xml.Unmarshal(XMLdata, &c)

Below is the full code of reading the XML file Employees.xml

 package main

 import (
 "fmt"
 "io/ioutil"
 "os"
 "encoding/xml"
 )


 type Staff struct {
 XMLName xml.Name `xml:"staff"`
 ID int `xml:"id"`
 FirstName string `xml:"firstname"`
 LastName string `xml:"lastname"`
 UserName string `xml:"username"`
 }

 type Company struct {
 XMLName xml.Name `xml:"company"`
 Staffs []Staff `xml:"staff"`
 }

 func (s Staff) String() string {
 return fmt.Sprintf("\t ID : %d - FirstName : %s - LastName : %s - UserName : %s \n", s.ID,  s.FirstName , s.LastName, s.UserName)
 }


 func main() {
 xmlFile, err := os.Open("Employees.xml")
 if err != nil {
 fmt.Println("Error opening file:", err)
 return
 }
 defer xmlFile.Close()

 XMLdata, _ := ioutil.ReadAll(xmlFile)

 var c Company
 xml.Unmarshal(XMLdata, &c)

 fmt.Println(c.Staffs)
 }

and the output after parsing.

go run parseEmployee.go

ID : 101 - FirstName : Derek - LastName : Young - UserName : derekyoung

ID : 102 - FirstName : John - LastName : Smith - UserName : johnsmith

Hope this tutorial is helpful enough to you. Please leave your comment below if you have any question.

  See also : Golang : How to read CSV file





By Adam Ng

IF you gain some knowledge or the information here solved your programming problem. Please consider donating to the less fortunate or some charities that you like. Apart from donation, planting trees, volunteering or reducing your carbon footprint will be great too.


Advertisement