First implementation of an atom feed

link.go

@@ -0,0 +1,39 @@
+package atomfeed
+
+import (
+	"errors"
+	"fmt"
+)
+
+type Link struct {
+	*CommonAttributes
+	Title    *Text       `xml:"title,attr,omitempty"`
+	Content  *Content    `xml:"content"`
+	Href     URI         `xml:"href,attr"`
+	Rel      string      `xml:"rel,attr,omitempty"`
+	Type     MediaType   `xml:"type,attr,omitempty"`
+	HrefLang LanguageTag `xml:"hreflang,attr,omitempty"`
+	Length   uint        `xml:"length,attr,omitempty"`
+}
+
+func (l *Link) Check() error {
+	if l.Href == "" {
+		return errors.New("href attribute of link empty")
+	}
+
+	if l.Title != nil {
+		if err := (*l.Title).Check(); err != nil {
+			return fmt.Errorf("title attribute of link %v: %v", l.Href, err)
+		}
+	}
+
+	if l.Content == nil {
+		return fmt.Errorf("no content element of link %v", l.Href)
+	} else {
+		if err := (*l.Content).Check(); err != nil {
+			return fmt.Errorf("content element of link %v: %v", l.Href, err)
+		}
+	}
+
+	return nil
+}