Refactor utils/utils, fixes #11923

Signed-off-by: Antonio Murdaca <me@runcom.ninja>

ioutils/writers.go

@@ -37,3 +37,24 @@ func NewWriteCloserWrapper(r io.Writer, closer func() error) io.WriteCloser {
 		closer: closer,
 	}
 }
+
+// Wrap a concrete io.Writer and hold a count of the number
+// of bytes written to the writer during a "session".
+// This can be convenient when write return is masked
+// (e.g., json.Encoder.Encode())
+type WriteCounter struct {
+	Count  int64
+	Writer io.Writer
+}
+
+func NewWriteCounter(w io.Writer) *WriteCounter {
+	return &WriteCounter{
+		Writer: w,
+	}
+}
+
+func (wc *WriteCounter) Write(p []byte) (count int, err error) {
+	count, err = wc.Writer.Write(p)
+	wc.Count += int64(count)
+	return
+}