sync: Return the reader from importer instead of writing to a given Writer

admin/sync/file.go

@@ -34,8 +34,8 @@ type Importer interface {
 	// Then calls back the next function, with the downloaded location and the original URI.
 	// Callback return is forwarded.
 	importFile(URI string, next func(string, string) (interface{}, error)) (interface{}, error)
-	// getFile write to the given buffer, the file at the given location.
-	getFile(filename string, writer *bufio.Writer) error
+	// getFileReader returns a reader to the requested file.
+	getFile(filename string) (io.Reader, error)
 	// listDir returns a list of the files and subdirectories contained inside the directory at the given location.
 	listDir(filename string) ([]string, error)
 	// stat returns many information about the given file: such as last modification date, size, ...
@@ -105,7 +105,18 @@ func getFileSize(i Importer, URI string) (size int64, err error) {
 func GetFile(i Importer, URI string, writer *bufio.Writer) error {
 	// Import file if it exists
 	if i.exists(URI) {
-		return i.getFile(URI, writer)
+		fd, err := i.getFile(URI)
+		if err != nil {
+			return err
+		}
+
+		if fdc, ok := fd.(io.ReadCloser); ok {
+			defer fdc.Close()
+		}
+		writer.ReadFrom(fd)
+
+		writer.Flush()
+		return nil
 	}
 
 	// Try to find file parts
@@ -120,13 +131,21 @@ func GetFile(i Importer, URI string, writer *bufio.Writer) error {
 				for _, file := range files {
 					if matched, _ := path.Match(fname+"[0-9][0-9]", file); matched {
 						found = true
-						if err := i.getFile(path.Join(dirname, file), writer); err != nil {
+
+						fd, err := i.getFile(path.Join(dirname, file))
+						if err != nil {
 							return err
 						}
+
+						if fdc, ok := fd.(io.ReadCloser); ok {
+							defer fdc.Close()
+						}
+						writer.ReadFrom(fd)
 					}
 				}
 
 				if found {
+					writer.Flush()
 					return nil
 				}
 			}