func (c *Client) dumpHTTP(req *http.Request, resp *http.Response) {
	// Starts http dump.
	_, err := fmt.Fprintln(c.TraceOutput, "---------START-HTTP---------")
	if err != nil {
		return
	}

	// Filter out Signature field from Authorization header.
	origAuth := req.Header.Get("Authorization")
	if origAuth != "" {
		req.Header.Set("Authorization", "**REDACTED**")
	}

	// Only display request header.