예제 #1
0
// Fast path for blobpacked.
func fileInfoPacked(sh *search.Handler, src blob.Fetcher, req *http.Request, file blob.Ref) (packFileInfo fileInfo, ok bool) {
	if sh == nil {
		return fileInfo{whyNot: "no search"}, false
	}
	wf, ok := src.(blobserver.WholeRefFetcher)
	if !ok {
		return fileInfo{whyNot: "fetcher type"}, false
	}
	if req != nil && req.Header.Get("Range") != "" {
		// TODO: not handled yet. Maybe not even important,
		// considering rarity.
		return fileInfo{whyNot: "range header"}, false
	}
	des, err := sh.Describe(&search.DescribeRequest{BlobRef: file})
	if err != nil {
		log.Printf("ui: fileInfoPacked: skipping fast path due to error from search: %v", err)
		return fileInfo{whyNot: "search error"}, false
	}
	db, ok := des.Meta[file.String()]
	if !ok || db.File == nil {
		return fileInfo{whyNot: "search index doesn't know file"}, false
	}
	fi := db.File
	if !fi.WholeRef.Valid() {
		return fileInfo{whyNot: "no wholeref from search index"}, false
	}

	offset := int64(0)
	rc, wholeSize, err := wf.OpenWholeRef(fi.WholeRef, offset)
	if err == os.ErrNotExist {
		return fileInfo{whyNot: "WholeRefFetcher returned ErrNotexist"}, false
	}
	if wholeSize != fi.Size {
		log.Printf("ui: fileInfoPacked: OpenWholeRef size %d != index size %d; ignoring fast path", wholeSize, fi.Size)
		return fileInfo{whyNot: "WholeRefFetcher and index don't agree"}, false
	}
	if err != nil {
		log.Printf("ui: fileInfoPacked: skipping fast path due to error from WholeRefFetcher (%T): %v", src, err)
		return fileInfo{whyNot: "WholeRefFetcher error"}, false
	}
	return fileInfo{
		mime:  fi.MIMEType,
		name:  fi.FileName,
		size:  fi.Size,
		rs:    readerutil.NewFakeSeeker(rc, fi.Size-offset),
		close: rc.Close,
	}, true
}