presto-proxy/src/main/java/io/prestosql/proxy/ProxyResource.java/ProxyResource/rewriteUri
class ProxyResource:    private String rewriteUri(UriInfo uriInfo, String uri)
    {
        return uriInfo.getAbsolutePathBuilder()
                .replacePath("/v1/proxy")
                .queryParam("uri", uri)
                .queryParam("hmac", hmac.hashString(uri, UTF_8))
                .build()
                .toString();
    }