Golang encoding/xml

go's builtin library for parsing xml.
See also: golang encoding, xml

A more detailed introduction to go's encoding interface can be seen in golang encoding/json.

NOTE:

Golang's builtin xml library does not support the full xml spec.
Confirm your needs are supported before using it

Documentation

official docs

https://pkg.go.dev/encoding/xml@go1.18.3

Tutorials

tutorialedge

https://tutorialedge.net/golang/parsing-xml-with-golang/

Struct Tags

See full details here

type User struct {
    Name  `xml:"Name"`       // <User><Name>value</Name></User>
    Color `xml:"color,attr"` // <User color="value"></User>
    Skip  `xml:"-"`          // <User></User>
}

Known issues:

• xml namespaces are not supported https://github.com/golang/go/issues/11496
• schema validation does not appear to be supported

Serializing

type User struct {
    Id   int    `xml:"id"`
    Name string `xml:"name,attr"`
}

func main() {
    user := User{123, "will"}
    bytes, _ := xml.Marshal(&user)
    fmt.Println(string(bytes))  // <User name="will"><id>123</id></User>
}

Deserialization

Basics

type User struct {
    Id   int    `xml:"id"`
    Name string `xml:"name,attr"`
}

func main() {
    user := User{123, "will"}
    bytes, _ := xml.Marshal(&user)
    fmt.Println(string(bytes))  // <User name="will"><id>123</id></User>
}

Non-Homogenous XML

XML is generally not homogenous.
Record each possible sub-element as a field on your object.
If an element can occur multiple times, declare it as an array.
You can ignore elements by not defining fields for them.

encoded := `
  <mediawiki>
      <siteinfo>
          abc
      </siteinfo>
      <page>
          <title>Main Page</title>
      </page>
      <page>
          <title>Linux</title>
      </page>
  </mediawiki>
`

type Result struct {
    XMLName  xml.Name `xml:"mediawiki"` // root node
    SiteInfo string   `xml:"siteinfo"`  // only one 'siteinfo' element under 'mediawiki'
    Page     []Page   `xml:"page"`      // multiple 'page' elements under 'mediawiki'
}

type Page struct {
    Title string `xml:"title"`
}

var result Result
xml.Unmarshall([]byte(encoded), &result)
fmt.Println(result.Page[0].Title.Text)  // Linux