Dump stdin to a temporary file in kubectl replace --force

pkg/kubectl/cmd/util/helpers.go

@@ -406,3 +406,28 @@ func Merge(dst runtime.Object, fragment, kind string) (runtime.Object, error) {
 	}
 	return out, nil
 }
+
+// DumpReaderToFile writes all data from the given io.Reader to the specified file
+// (usually for temporary use).
+func DumpReaderToFile(reader io.Reader, filename string) error {
+	f, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
+	defer f.Close()
+	if err != nil {
+		return err
+	}
+	buffer := make([]byte, 1024)
+	for {
+		count, err := reader.Read(buffer)
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		_, err = f.Write(buffer[:count])
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}