Fixes issue gorillaGH-25 for RSS feeds.

Adds the ability to add custom fields with a namespace to the RSS feed.

feed.go

@@ -35,9 +35,11 @@ type Item struct {
 	Created     time.Time
 	Enclosure   *Enclosure
 	Content     string
+	Extension   []interface{}
 }
 
 type Feed struct {
+	Attrs       []xml.Attr
 	Title       string
 	Link        *Link
 	Description string
@@ -56,6 +58,57 @@ func (f *Feed) Add(item *Item) {
 	f.Items = append(f.Items, item)
 }
 
+func (f *Feed) AddAttribute(name, nsURI string) {
+	f.Attrs = append(f.Attrs, xml.Attr{
+		Name:  xml.Name{Local: name},
+		Value: nsURI,
+	})
+}
+
+func (i *Item) AddExtension(extend interface{}) {
+	i.Extension = append(i.Extension, extend)
+}
+
+func (i *Item) AddExtensionString(name string, nsURI string, value string) {
+	i.Extension = append(i.Extension, struct {
+		XMLName xml.Name
+		Text    string `xml:",chardata"`
+	}{
+		XMLName: xml.Name{Local: name, Space: nsURI},
+		Text:    value,
+	})
+}
+
+func (i *Item) AddExtensionInt(name string, nsURI string, value int) {
+	i.Extension = append(i.Extension, struct {
+		XMLName xml.Name
+		Number  int `xml:",chardata"`
+	}{
+		XMLName: xml.Name{Local: name, Space: nsURI},
+		Number:  value,
+	})
+}
+
+func (i *Item) AddExtensionUint(name string, nsURI string, value uint) {
+	i.Extension = append(i.Extension, struct {
+		XMLName xml.Name
+		Number  uint `xml:",chardata"`
+	}{
+		XMLName: xml.Name{Local: name, Space: nsURI},
+		Number:  value,
+	})
+}
+
+func (i *Item) AddExtensionFloat64(name string, nsURI string, value float64) {
+	i.Extension = append(i.Extension, struct {
+		XMLName xml.Name
+		Number  float64 `xml:",chardata"`
+	}{
+		XMLName: xml.Name{Local: name, Space: nsURI},
+		Number:  value,
+	})
+}
+
 // returns the first non-zero time formatted as a string or ""
 func anyTimeFormat(format string, times ...time.Time) string {
 	for _, t := range times {

rss.go

@@ -41,24 +41,25 @@ type RssTextInput struct {
 }
 
 type RssFeed struct {
-	XMLName        xml.Name `xml:"channel"`
-	Title          string   `xml:"title"`       // required
-	Link           string   `xml:"link"`        // required
-	Description    string   `xml:"description"` // required
-	Language       string   `xml:"language,omitempty"`
-	Copyright      string   `xml:"copyright,omitempty"`
-	ManagingEditor string   `xml:"managingEditor,omitempty"` // Author used
-	WebMaster      string   `xml:"webMaster,omitempty"`
-	PubDate        string   `xml:"pubDate,omitempty"`       // created or updated
-	LastBuildDate  string   `xml:"lastBuildDate,omitempty"` // updated used
-	Category       string   `xml:"category,omitempty"`
-	Generator      string   `xml:"generator,omitempty"`
-	Docs           string   `xml:"docs,omitempty"`
-	Cloud          string   `xml:"cloud,omitempty"`
-	Ttl            int      `xml:"ttl,omitempty"`
-	Rating         string   `xml:"rating,omitempty"`
-	SkipHours      string   `xml:"skipHours,omitempty"`
-	SkipDays       string   `xml:"skipDays,omitempty"`
+	XMLName        xml.Name   `xml:"channel"`
+	Attrs          []xml.Attr `xml:",attr"`
+	Title          string     `xml:"title"`       // required
+	Link           string     `xml:"link"`        // required
+	Description    string     `xml:"description"` // required
+	Language       string     `xml:"language,omitempty"`
+	Copyright      string     `xml:"copyright,omitempty"`
+	ManagingEditor string     `xml:"managingEditor,omitempty"` // Author used
+	WebMaster      string     `xml:"webMaster,omitempty"`
+	PubDate        string     `xml:"pubDate,omitempty"`       // created or updated
+	LastBuildDate  string     `xml:"lastBuildDate,omitempty"` // updated used
+	Category       string     `xml:"category,omitempty"`
+	Generator      string     `xml:"generator,omitempty"`
+	Docs           string     `xml:"docs,omitempty"`
+	Cloud          string     `xml:"cloud,omitempty"`
+	Ttl            int        `xml:"ttl,omitempty"`
+	Rating         string     `xml:"rating,omitempty"`
+	SkipHours      string     `xml:"skipHours,omitempty"`
+	SkipDays       string     `xml:"skipDays,omitempty"`
 	Image          *RssImage
 	TextInput      *RssTextInput
 	Items          []*RssItem
@@ -77,6 +78,7 @@ type RssItem struct {
 	Guid        string `xml:"guid,omitempty"`    // Id used
 	PubDate     string `xml:"pubDate,omitempty"` // created or updated
 	Source      string `xml:"source,omitempty"`
+	Extensions  interface{}
 }
 
 type RssEnclosure struct {
@@ -99,6 +101,7 @@ func newRssItem(i *Item) *RssItem {
 		Description: i.Description,
 		Guid:        i.Id,
 		PubDate:     anyTimeFormat(time.RFC1123Z, i.Created, i.Updated),
+		Extensions:  i.Extension,
 	}
 	if len(i.Content) > 0 {
 		item.Content = &RssContent{Content: i.Content}
@@ -136,6 +139,7 @@ func (r *Rss) RssFeed() *RssFeed {
 	}
 
 	channel := &RssFeed{
+		Attrs:          r.Attrs,
 		Title:          r.Title,
 		Link:           r.Link.Href,
 		Description:    r.Description,

rss_test.go

@@ -0,0 +1,77 @@
+package feeds
+
+import (
+	"bytes"
+	"testing"
+	"time"
+)
+
+func TestRssFeedExtensions(t *testing.T) {
+	var rssOutput = `<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:content="http://purl.org/rss/1.0/modules/content/">
+  <channel test="https://example.com/test/uri">
+    <title>Example</title>
+    <link>https://rss.example.com</link>
+    <description>Example Example</description>
+    <copyright>copyright © Example</copyright>
+    <managingEditor>Example (Example)</managingEditor>
+    <pubDate>Wed, 16 Jan 2013 21:52:35 -0500</pubDate>
+    <item>
+      <title>Example example</title>
+      <link>https://example.com/link</link>
+      <description>example</description>
+      <content:encoded><![CDATA[Example example example, example example...]]></content:encoded>
+      <author>Jason Moiron</author>
+      <pubDate>Wed, 16 Jan 2013 21:52:35 -0500</pubDate>
+      <test:version>v1</test:version>
+      <test:example>1234567890</test:example>
+    </item>
+  </channel>
+</rss>`
+
+	now, err := time.Parse(time.RFC3339, "2013-01-16T21:52:35-05:00")
+	if err != nil {
+		t.Error(err)
+	}
+	tz := time.FixedZone("EST", -5*60*60)
+	now = now.In(tz)
+
+	feed := &Feed{
+		Title:       "Example",
+		Link:        &Link{Href: "https://rss.example.com"},
+		Description: "Example Example",
+		Author:      &Author{Name: "Example", Email: "Example"},
+		Created:     now,
+		Copyright:   "copyright © Example",
+	}
+
+	feed.Items = []*Item{
+		{
+			Title:       "Example example",
+			Link:        &Link{Href: "https://example.com/link"},
+			Description: "example",
+			Author:      &Author{Name: "Jason Moiron", Email: "[email protected]"},
+			Created:     now,
+			Content:     "Example example example, example example...",
+		},
+	}
+
+	feed.AddAttribute("test", "https://example.com/test/uri")
+	feed.Items[0].AddExtensionString("test:version", "", "v1")
+	feed.Items[0].AddExtensionInt("test:example", "", 1234567890)
+
+	rss, err := feed.ToRss()
+	if err != nil {
+		t.Errorf("unexpected error encoding RSS: %v", err)
+	}
+	if rss != rssOutput {
+		t.Errorf("Rss not what was expected.  Got:\n%s\n\nExpected:\n%s\n", rss, rssOutput)
+	}
+
+	var buf = new(bytes.Buffer)
+	if err := feed.WriteRss(buf); err != nil {
+		t.Errorf("unexpected error writing RSS: %v", err)
+	}
+	if got := buf.String(); got != rssOutput {
+		t.Errorf("Rss not what was expected.  Got:\n%s\n\nExpected:\n%s\n", got, rssOutput)
+	}
+}