How to parse an XML document in Go

Tagged go, xml, encoding, golang, rss, parser  Languages go

This example shows how to fetch and parse an XML feed with Go.

Save this in main_test.go:

package main

import (
    "bytes"
    "code.google.com/p/go-charset/charset"
    _ "code.google.com/p/go-charset/data" // Import charset configuration files
    "encoding/xml"
    "io/ioutil"
    "log"
    "net/http"
    "testing"
)

type RssFeed struct {
    XMLName xml.Name  `xml:"rss"`
    Items   []RssItem `xml:"channel>item"`
}

type RssItem struct {
    XMLName     xml.Name `xml:"item"`
    Title       string   `xml:"title"`
    Link        string   `xml:"link"`
    Description string   `xml:"description"`
    //NestedTag    string      xml:">nested>tags>"
}

func fetchURL(url string) []byte {
    resp, err := http.Get(url)
    if err != nil {
        log.Fatalf("unable to GET '%s': %s", url, err)
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        log.Fatalf("unable to read body '%s': %s", url, err)
    }
    return body
}

func parseXML(xmlDoc []byte, target interface{}) {
    reader := bytes.NewReader(xmlDoc)
    decoder := xml.NewDecoder(reader)
    // Fixes "xml: encoding \"windows-1252\" declared but Decoder.CharsetReader is nil"
    decoder.CharsetReader = charset.NewReader
    if err := decoder.Decode(target); err != nil {
        log.Fatalf("unable to parse XML '%s':\n%s", err, xmlDoc)
    }
}

func TestParseReport(t *testing.T) {
    var rssFeed = &RssFeed{}
    xmlDoc := fetchURL("https://news.ycombinator.com/rss")
    parseXML(xmlDoc, &rssFeed)
    for _, item := range rssFeed.Items {
        log.Printf("%s: %s", item.Title, item.Link)
    }
}

Run the code with go test.