minimal vend

vendor/github.com/mmcdole/gofeed/detector.go

@@ -0,0 +1,48 @@
+package gofeed
+
+import (
+	"io"
+	"strings"
+
+	"github.com/mmcdole/gofeed/internal/shared"
+	"github.com/mmcdole/goxpp"
+)
+
+// FeedType represents one of the possible feed
+// types that we can detect.
+type FeedType int
+
+const (
+	// FeedTypeUnknown represents a feed that could not have its
+	// type determiend.
+	FeedTypeUnknown FeedType = iota
+	// FeedTypeAtom repesents an Atom feed
+	FeedTypeAtom
+	// FeedTypeRSS represents an RSS feed
+	FeedTypeRSS
+)
+
+// DetectFeedType attempts to determine the type of feed
+// by looking for specific xml elements unique to the
+// various feed types.
+func DetectFeedType(feed io.Reader) FeedType {
+	p := xpp.NewXMLPullParser(feed, false, shared.NewReaderLabel)
+
+	xmlBase := shared.XMLBase{}
+	_, err := xmlBase.FindRoot(p)
+	if err != nil {
+		return FeedTypeUnknown
+	}
+
+	name := strings.ToLower(p.Name)
+	switch name {
+	case "rdf":
+		return FeedTypeRSS
+	case "rss":
+		return FeedTypeRSS
+	case "feed":
+		return FeedTypeAtom
+	default:
+		return FeedTypeUnknown
+	}
+}