rename packaages

src/parser/feed.go

@@ -0,0 +1,100 @@
+package parser
+
+import (
+	"bytes"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"io"
+	"net/url"
+	"strings"
+	"time"
+)
+
+var UnknownFormat = errors.New("unknown feed format")
+
+type processor func(r io.Reader) (*Feed, error)
+
+func sniff(lookup string) (string, processor) {
+	lookup = strings.TrimSpace(lookup)
+	switch lookup[0] {
+	case '<':
+		decoder := xmlDecoder(strings.NewReader(lookup))
+		for {
+			token, _ := decoder.Token()
+			if token == nil {
+				break
+			}
+			if el, ok := token.(xml.StartElement); ok {
+				switch el.Name.Local {
+				case "rss":
+					return "rss", ParseRSS
+				case "RDF":
+					return "rdf", ParseRDF
+				case "feed":
+					return "atom", ParseAtom
+				}
+			}
+		}
+	case '{':
+		return "json", ParseJSON
+	}
+	return "", nil
+}
+
+func Parse(r io.Reader) (*Feed, error) {
+	lookup := make([]byte, 1024)
+	if _, err := r.Read(lookup); err != nil {
+		return nil, fmt.Errorf("Failed to read input: %s", err)
+	}
+
+	_, callback := sniff(string(lookup))
+	if callback == nil {
+		return nil, UnknownFormat
+	}
+
+	feed, err := callback(io.MultiReader(bytes.NewReader(lookup), r))
+	if feed != nil {
+		feed.cleanup()
+	}
+	return feed, err
+}
+
+func (feed *Feed) cleanup() {
+	feed.Title = strings.TrimSpace(feed.Title)
+	feed.SiteURL = strings.TrimSpace(feed.SiteURL)
+	for i, item := range feed.Items {
+		feed.Items[i].GUID = strings.TrimSpace(item.GUID)
+		feed.Items[i].URL = strings.TrimSpace(item.URL)
+		feed.Items[i].Title = strings.TrimSpace(item.Title)
+		feed.Items[i].Content = strings.TrimSpace(item.Content)
+	}
+}
+
+func (feed *Feed) SetMissingDatesTo(newdate time.Time) {
+	for i, item := range feed.Items {
+		if item.Date.Equal(defaultTime) {
+			feed.Items[i].Date = newdate
+		}
+	}
+}
+
+func (feed *Feed) TranslateURLs(base string) error {
+	baseUrl, err := url.Parse(base)
+	if err != nil {
+		return fmt.Errorf("failed to parse base url: %#v", base)
+	}
+	siteUrl, err := url.Parse(feed.SiteURL)
+	if err != nil {
+		return fmt.Errorf("failed to parse feed url: %#v", feed.SiteURL)
+	}
+	feed.SiteURL = baseUrl.ResolveReference(siteUrl).String()
+	for _, item := range feed.Items {
+		itemUrl, err := url.Parse(item.URL)
+		if err != nil {
+			return fmt.Errorf("failed to parse item url: %#v", item.URL)
+		}
+		item.URL = siteUrl.ResolveReference(itemUrl).String()
+	}
+	return nil
+}