Package restructure

The package has been moved around to give better structure. Individual
components have been put into separate files.

ISO-8859-1.go

@@ -0,0 +1,91 @@
+package rss
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"strings"
+	"unicode/utf8"
+)
+
+// ISO-8859-1 support
+
+type charsetISO88591er struct {
+    r   io.ByteReader
+    buf *bytes.Buffer
+}
+
+func newCharsetISO88591(r io.Reader) *charsetISO88591er {
+    buf := bytes.NewBuffer(make([]byte, 0, utf8.UTFMax))
+    return &charsetISO88591er{r.(io.ByteReader), buf}
+}
+
+func (cs *charsetISO88591er) ReadByte() (b byte, err error) {
+    // http://unicode.org/Public/MAPPINGS/ISO8859/8859-1.TXT
+    // Date: 1999 July 27; Last modified: 27-Feb-2001 05:08
+    if cs.buf.Len() <= 0 {
+        r, err := cs.r.ReadByte()
+        if err != nil {
+            return 0, err
+        }
+        if r < utf8.RuneSelf {
+            return r, nil
+        }
+        cs.buf.WriteRune(rune(r))
+    }
+    return cs.buf.ReadByte()
+}
+
+func (cs *charsetISO88591er) Read(p []byte) (int, error) {
+    // Use ReadByte method.
+    return 0, errors.New("Use ReadByte()")
+}
+
+func isCharset(charset string, names []string) bool {
+    charset = strings.ToLower(charset)
+    for _, n := range names {
+        if charset == strings.ToLower(n) {
+            return true
+        }
+    }
+    return false
+}
+
+func isCharsetISO88591(charset string) bool {
+    // http://www.iana.org/assignments/character-sets
+    // (last updated 2010-11-04)
+    names := []string{
+        // Name
+        "ISO_8859-1:1987",
+        // Alias (preferred MIME name)
+        "ISO-8859-1",
+        // Aliases
+        "iso-ir-100",
+        "ISO_8859-1",
+        "latin1",
+        "l1",
+        "IBM819",
+        "CP819",
+        "csISOLatin1",
+    }
+    return isCharset(charset, names)
+}
+
+func isCharsetUTF8(charset string) bool {
+    names := []string{
+        "UTF-8",
+        // Default
+        "",
+    }
+    return isCharset(charset, names)
+}
+
+func charsetReader(charset string, input io.Reader) (io.Reader, error) {
+    switch {
+    case isCharsetUTF8(charset):
+        return input, nil
+    case isCharsetISO88591(charset):
+        return newCharsetISO88591(input), nil
+    }
+    return nil, errors.New("CharsetReader: unexpected charset: " + charset)
+}

database.go

@@ -0,0 +1,36 @@
+package rss
+
+var database *db
+
+func init() {
+	database = NewDB()
+	go database.Run()
+}
+
+type db struct {
+	req chan string
+	res chan bool
+	known map[string]struct{}
+}
+
+func (d *db) Run() {
+	d.known = make(map[string]struct{})
+	var s string
+
+	for {
+		s = <- d.req
+		if _, ok := d.known[s]; ok {
+			d.res <- true
+		} else {
+			d.res <- false
+			d.known[s] = struct{}{}
+		}
+	}
+}
+
+func NewDB() *db {
+	out := new(db)
+	out.req = make(chan string)
+	out.res = make(chan bool)
+	return out
+}

rss 2.0.go

@@ -0,0 +1,133 @@
+package rss
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+)
+
+func parseRSS2(data []byte, read *db) (*Feed, error) {
+	feed := rss2_0Feed{}
+	p := xml.NewDecoder(bytes.NewReader(data))
+	p.CharsetReader = charsetReader
+	err := p.Decode(&feed)
+	if err != nil {
+		return nil, err
+	}
+	if feed.Channel == nil {
+		return nil, fmt.Errorf("Error: no channel found in %q.", string(data))
+	}
+
+	channel := feed.Channel
+
+	out := new(Feed)
+	out.Title = channel.Title
+	out.Description = channel.Description
+	out.Link = channel.Link
+	out.Image = channel.Image.Image()
+	if channel.MinsToLive != 0 {
+		sort.Ints(channel.SkipHours)
+		next := time.Now().Add(time.Duration(channel.MinsToLive) * time.Minute)
+		for _, hour := range channel.SkipHours {
+			if hour == next.Hour() {
+				next.Add(time.Duration(60 - next.Minute()) * time.Minute)
+			}
+		}
+		trying := true
+		for trying {
+			trying = false
+			for _, day := range channel.SkipDays {
+				if strings.Title(day) == next.Weekday().String() {
+					next.Add(time.Duration(24 - next.Hour()) * time.Hour)
+					trying = true
+					break
+				}
+			}
+		}
+
+		out.Refresh = next
+	}
+
+	if out.Refresh.IsZero() {
+		out.Refresh = time.Now().Add(10 * time.Minute)
+	}
+
+	if channel.Items == nil {
+		return nil, fmt.Errorf("Error: no feeds found in %q.", string(data))
+	}
+
+	out.Items = make([]*Item, 0, len(channel.Items))
+
+	// Process items.
+	for _, item := range channel.Items {
+
+		// Skip items already known.
+		if read.req <- item.ID; <- read.res {
+			continue
+		}
+
+		next := new(Item)
+		next.Title = item.Title
+		next.Content = item.Content
+		next.Link = item.Link
+		if item.Date != "" {
+			next.Date, err = parseTime(item.Date)
+			if err != nil {
+				return nil, err
+			}
+		}
+		next.ID = item.ID
+		next.Read = false
+
+		out.Items = append(out.Items, next)
+		out.Unread++
+	}
+
+	return out, nil
+}
+
+type rss2_0Feed struct {
+	XMLName  xml.Name       `xml:"rss"`
+	Channel  *rss2_0Channel `xml:"channel"`
+}
+
+type rss2_0Channel struct {
+	XMLName     xml.Name     `xml:"channel"`
+	Title       string       `xml:"title"`
+	Description string       `xml:"description"`
+	Link        string       `xml:"link"`
+	Image       rss2_0Image  `xml:"image"`
+	Items       []rss2_0Item `xml:"item"`
+	MinsToLive  int          `xml:"ttl"`
+	SkipHours   []int        `xml:"skipHours>hour"`
+	SkipDays    []string     `xml:"skipDays>day"`
+}
+
+type rss2_0Item struct {
+	XMLName xml.Name `xml:"item"`
+	Title   string   `xml:"title"`
+	Content string   `xml:"description"`
+	Link    string   `xml:"link"`
+	Date    string   `xml:"pubDate"`
+	ID      string   `xml:"guid"`
+}
+
+type rss2_0Image struct {
+	XMLName xml.Name `xml:"image"`
+	Title   string   `xml:"title"`
+	Url     string   `xml:"url"`
+	Height  int      `xml:"height"`
+	Width   int      `xml:"width"`
+}
+
+func (i *rss2_0Image) Image() *Image {
+	out := new(Image)
+	out.Title = i.Title
+	out.Url = i.Url
+	out.Height = uint32(i.Height)
+	out.Width = uint32(i.Width)
+	return out
+}