if (version == null) {
// try with ES version from downloads
URL pluginUrl = new URL("https://github.com/downloads/" + userName + "/" + repoName + "/" + repoName + "-" + Version.number() + ".zip");
System.out.println("Trying " + pluginUrl.toExternalForm() + "...");
try {
downloadHelper.download(pluginUrl, pluginFile, new HttpDownloadHelper.VerboseProgress(System.out));
downloaded = true;
} catch (IOException e) {
// try a tag with ES version
pluginUrl = new URL("https://github.com/" + userName + "/" + repoName + "/zipball/v" + Version.number());
System.out.println("Trying " + pluginUrl.toExternalForm() + "...");