working commit

pkg/client/client.go

@@ -81,16 +81,17 @@ func (cli *Client) FileExists(ctx context.Context, ref string) (bool, error) {
 	return res, err
 }
 
-func (cli *Client) GetFile(ctx context.Context, ref, filename string) error {
+func (cli *Client) GetFile(ctx context.Context, ref, filename string) (int64, error) {
 	var err error
+	var size int64
 	ref, err = convertFileLink(ref)
 	if err != nil {
-		return err
+		return size, err
 	}
 
 	req, err := http.NewRequestWithContext(ctx, http.MethodGet, ref, nil)
 	if err != nil {
-		return err
+		return size, err
 	}
 	transport := &http.Transport{
 		TLSClientConfig: &tls.Config{
@@ -102,29 +103,42 @@ func (cli *Client) GetFile(ctx context.Context, ref, filename string) error {
 	}
 	resp, err := client.Do(req)
 	if err != nil {
-		return err
+		return size, err
 	}
 	defer resp.Body.Close()
 
+	contentLength := resp.Header.Get("Content-Length")
+	if contentLength == "" {
+		err = fmt.Errorf("Empty Content-Length received")
+		return size, err
+	}
 	if resp.StatusCode != http.StatusOK {
 		err := fmt.Errorf("Received wrong status code: %s", resp.Status)
-		return err
+		return size, err
+	}
+	declSize, err := strconv.ParseInt(contentLength, 10, 64)
+	if err != nil {
+		err = fmt.Errorf("Wrong Content-Length value: %v", err)
+		return size, err
 	}
-
 	dirname := filepath.Dir(filename)
 	err = os.MkdirAll(dirname, 0750)
 	if err != nil {
-		return err
+		return size, err
 	}
 	file, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE, 0640)
 	if err != nil {
-		return err
+		return size, err
 	}
-	_, err = io.Copy(file, resp.Body)
+	size, err = io.Copy(file, resp.Body)
 	if err != nil {
-		return err
+		return size, err
 	}
-	return err
+	if size != declSize {
+		err := fmt.Errorf("Mismatch Content-Length and recorded filesize")
+		return size, err
+	}
+	return size, err
 }
 
 func (cli *Client) PutFile(ctx context.Context, filename, ref string) error {