initial commit, general organization and likely broken atom implementation

Author: jmoiron

README.md

@@ -0,0 +1,8 @@
+Syndication (feed) generator library for golang.
+
+Usage:
+
+```golang
+
+```
+

atom.go

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+package syndicate
+
+import (
+	"encoding/xml"
+	"fmt"
+	"net/url"
+	"time"
+)
+
+// Generates Atom feed as XML
+
+const ns = "http://www.w3.org/2005/Atom"
+
+type atomSummary struct {
+	S    string `xml:",chardata"`
+	Type string `xml:"type,attr"`
+}
+
+type atomEntry struct {
+	XMLName xml.Name `xml:"entry"`
+	Title   string   `xml:"title"`
+	Link    *atomLink
+	Updated string       `xml:"updated"`
+	Id      string       `xml:"id"`
+	Summary *atomSummary `xml:"summary"`
+}
+
+type atomLink struct {
+	XMLName xml.Name `xml:"link"`
+	Href    string   `xml:"href,attr"`
+	Rel     string   `xml:"rel,attr"`
+}
+
+type atomFeed struct {
+	XMLName xml.Name `xml:"feed"`
+	Ns      string   `xml:"xmlns,attr"`
+	Title   string   `xml:"title"`
+	Link    *atomLink
+	Id      string `xml:"id"`
+	Updated string `xml:"updated"`
+	Entries []*atomEntry
+}
+
+type Atom struct {
+	*Feed
+}
+
+func newAtomEntry(i *Item) *atomEntry {
+	id := i.Id
+	// assume the description is html
+	s := &atomSummary{i.Description, "html"}
+
+	// try to get a single timestamp, since we only have one  in atom 
+	ts := i.Updated
+	if ts.IsZero() {
+		ts = i.Created
+	}
+	// <id>tag:blog.kowalczyk.info,2012-09-11:/item/1.html</id>
+	if len(id) == 0 {
+		// if there's no id set, try to create one, either from data or just a uuid
+		if len(i.Link.Href) > 0 && (!i.Created.IsZero() || !i.Updated.IsZero()) {
+			dateStr := ts.Format("2006-01-02")
+			host, path := i.Link.Href, "/invalid.html"
+			if url, err := url.Parse(i.Link.Href); err == nil {
+				host, path = url.Host, url.Path
+			}
+			id = fmt.Sprintf("tag:%s,%s:%s", host, dateStr, path)
+		} else {
+			id = "urn:uuid:" + NewUUID().String()
+		}
+	}
+	x := &atomEntry{
+		Title:   i.Title,
+		Link:    &atomLink{Href: i.Link.Href, Rel: i.Link.Rel},
+		Summary: s,
+		Id:      id,
+		Updated: i.Updated.Format(time.RFC3339)}
+	return x
+}
+
+func (a *Atom) FeedXml() interface{} {
+	feed := &atomFeed{
+		Ns:      ns,
+		Title:   a.Title,
+		Link:    &atomLink{Href: a.Link.Href, Rel: a.Link.Rel},
+		Id:      a.Link.Href,
+		Updated: a.Updated.Format(time.RFC3339)}
+	for _, e := range a.Items {
+		feed.Entries = append(feed.Entries, newAtomEntry(e))
+	}
+
+	return feed
+}

doc.go

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+/*
+Create feed output in RSS or Atom.
+
+*/
+package syndicate

feed.go

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+package syndicate
+
+import (
+	"encoding/xml"
+	"fmt"
+	"time"
+)
+
+type Link struct {
+	Href string
+	Rel  string
+}
+
+type Author struct {
+	Name  string
+	Email string
+}
+
+type Item struct {
+	Title       string
+	Link        *Link
+	Author      *Author
+	Description string // used as description in rss, summary in atom
+	Id          string // used as guid in rss, id in atom
+	Updated     time.Time
+	Created     time.Time
+}
+
+type Feed struct {
+	Title       string
+	Link        *Link
+	Author      *Author
+	Created     time.Time
+	Updated     time.Time
+	Description string
+	Subtitle    string
+	Id          string
+	Items       []*Item
+}
+
+func (f *Feed) Add(item *Item) {
+	f.Items = append(f.Items, item)
+}
+
+type XmlFeed interface {
+	FeedXml() interface{}
+}
+
+func ToXML(feed XmlFeed) (string, error) {
+	x := feed.FeedXml()
+	data, err := xml.MarshalIndent(x, " ", " ")
+	if err != nil {
+		return "", err
+	}
+	s := xml.Header[:len(xml.Header)-1] + string(data)
+	return s, nil
+}
+
+func (f *Feed) ToAtom() (string, error) {
+	a := &Atom{f}
+	return ToXML(a)
+}
+
+func (f *Feed) ToRss(version ...float64) (string, error) {
+	vers := 2.0
+	if len(version) > 0 {
+		vers = version[0]
+	}
+	/*
+		r := &RssFeed{f}
+		return ToXML(r)
+	*/
+	return fmt.Sprint(vers), nil
+}

feed_test.go

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+package syndicate

rss.go

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+package syndicate

uuid.go

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+package syndicate
+
+// relevant bits from https://github.com/abneptis/GoUUID/blob/master/uuid.go
+
+import (
+	"crypto/rand"
+	"fmt"
+)
+
+type UUID [16]byte
+
+func NewUUID() *UUID {
+	u := &UUID{}
+	_, err := rand.Read(u[:16])
+	if err != nil {
+		panic(err)
+	}
+
+	u[8] = (u[8] | 0x80) & 0xBf
+	u[6] = (u[6] | 0x40) & 0x4f
+	return u
+}
+
+func (u *UUID) String() string {
+	return fmt.Sprintf("%x-%x-%x-%x-%x", u[:4], u[4:6], u[6:8], u[8:10], u[10:])
+}

uuid_test.go

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+package syndicate
+
+import (
+	"testing"
+)
+
+func TestUUID(t *testing.T) {
+	s := NewUUID()
+	s2 := NewUUID()
+	if len(s) != 16 {
+		t.Errorf("Expecting len of 16, got %d\n", len(s))
+	}
+	if len(s.String()) != 36 {
+		t.Errorf("Expecting uuid hex string len of 36, got %d\n", len(s.String()))
+	}
+	if s == s2 {
+		t.Errorf("Expecting different UUIDs to be different, but they are the same.\n")
+	}
+}