inital impl

sitemap.go

@@ -0,0 +1,102 @@
+package gositemap
+
+import (
+	"encoding/xml"
+	"fmt"
+	"math"
+)
+
+type ChangeFrequency string
+
+const (
+	Always  ChangeFrequency = "always"
+	Hourly  ChangeFrequency = "hourly"
+	Daily   ChangeFrequency = "daily"
+	Weekly  ChangeFrequency = "weekly"
+	Monthly ChangeFrequency = "monthly"
+	Yearly  ChangeFrequency = "yearly"
+	Never   ChangeFrequency = "never"
+)
+
+func (f ChangeFrequency) String() string {
+	return string(f)
+}
+
+type urlSetXML struct {
+	XMLName xml.Name  `xml:"http://www.sitemaps.org/schemas/sitemap/0.9 urlset"`
+	URLs    []*urlXML `xml:"url"`
+}
+
+type urlXML struct {
+	Loc        string           `xml:"loc"`
+	LastMod    *string          `xml:"lastmod,omitempty"`
+	ChangeFreq *ChangeFrequency `xml:"changefreq,omitempty"`
+	Priority   *float64         `xml:"priority,omitempty"`
+}
+
+type siteMapIndexXML struct {
+	XMLName  xml.Name      `xml:"http://www.sitemaps.org/schemas/sitemap/0.9 sitemapindex"`
+	SiteMaps []*sitemapXML `xml:"sitemap"`
+}
+
+type sitemapXML struct {
+	Loc     string  `xml:"loc"`
+	LastMod *string `xml:"lastmod,omitempty"`
+}
+
+type SiteMap struct {
+	urls    []*urlXML
+	BaseURL string
+}
+
+func (m *SiteMap) AddURL(url string, lastMod *string, freq *ChangeFrequency, prio *float64) {
+	m.urls = append(m.urls, &urlXML{
+		Loc:        fmt.Sprintf("https://%s/%s", m.BaseURL, url),
+		LastMod:    lastMod,
+		ChangeFreq: freq,
+		Priority:   prio,
+	})
+}
+
+func prefixXML(content []byte) []byte {
+	return append([]byte(xml.Header), content...)
+}
+
+func (m *SiteMap) SiteMapIndex() ([]byte, error) {
+	nSiteMaps := int(math.Floor(float64(len(m.urls))/50000 + 1))
+
+	index := &siteMapIndexXML{}
+
+	for i := 0; i < nSiteMaps; i++ {
+		index.SiteMaps = append(index.SiteMaps, &sitemapXML{
+			Loc: fmt.Sprintf("https://%s/sitemap%d.xml", m.BaseURL, i),
+		})
+	}
+
+	res, err := xml.Marshal(index)
+	if err != nil {
+		return nil, err
+	}
+
+	return prefixXML(res), nil
+}
+
+func (m *SiteMap) SiteMap(id int) ([]byte, error) {
+	siteMap := &urlSetXML{}
+
+	var urls []*urlXML
+	if 50000*(id+1) >= len(m.urls) {
+		urls = m.urls[50000*id:]
+	} else {
+		urls = m.urls[50000*id : 50000*(id+1)]
+	}
+
+	siteMap.URLs = append(siteMap.URLs, urls...)
+
+	res, err := xml.Marshal(siteMap)
+	if err != nil {
+		return nil, err
+	}
+
+	return prefixXML(res), nil
+}