private static HttpRequestMessage massageRequestURI(HttpRequestMessage request) {
        SessionContext context = request.getContext();
        String modifiedPath;
        HttpQueryParams modifiedQueryParams = null;
        String uri = null;

        if (context.get("requestURI") != null) {
            uri = (String) context.get("requestURI");
        }

        // If another filter has specified an overrideURI, then use that instead of requested URI.
        Object override = context.get("overrideURI");
        if (override != null) {
            uri = override.toString();
        }

        if (uri != null) {
            int index = uri.indexOf('?');
            if (index != -1) {
                // Strip the query string off of the URI.
                String paramString = uri.substring(index + 1);
                modifiedPath = uri.substring(0, index);

                try {
                    paramString = URLDecoder.decode(paramString, "UTF-8");
                    modifiedQueryParams = new HttpQueryParams();
                    StringTokenizer stk = new StringTokenizer(paramString, "&");
                    while (stk.hasMoreTokens()) {
                        String token = stk.nextToken();
                        int idx = token.indexOf("=");
                        if (idx != -1) {
                            String key = token.substring(0, idx);
                            String val = token.substring(idx + 1);
                            modifiedQueryParams.add(key, val);
                        }
                    }
                } catch (UnsupportedEncodingException e) {
                    logger.error("Error decoding url query param - {}", paramString, e);
                }
            } else {
                modifiedPath = uri;
            }

            request.setPath(modifiedPath);
            if (modifiedQueryParams != null) {
                request.setQueryParams(modifiedQueryParams);
            }
        }

        return request;
    }
Request is replayable on a different origin IFF
A) we have not started to send response back to the client  AND
B) we have not lost any of its body chunks
zuul-core/src/main/java/com/netflix/zuul/filters/endpoint/ProxyEndpoint.java