@VisibleForTesting
    static void setupAndModifyConfiguration(
            Configuration configuration, String currDir, Map<String, String> variables)
            throws Exception {
        final String localDirs = variables.get(Environment.LOCAL_DIRS.key());
        LOG.info("Current working/local Directory: {}", localDirs);

        BootstrapTools.updateTmpDirectoriesInConfiguration(configuration, localDirs);

        setupConfigurationFromVariables(configuration, currDir, variables);
    }
@Test
    public void testDefaultKerberosKeytabConfiguration() throws Exception {
        final String resourceDirPath =
                Paths.get("src", "test", "resources").toAbsolutePath().toString();

        final Map<String, String> envs = new HashMap<>(2);
        envs.put(YarnConfigKeys.KEYTAB_PRINCIPAL, "testuser1@domain");
        envs.put(YarnConfigKeys.REMOTE_KEYTAB_PATH, resourceDirPath);
        // Local keytab path will be populated from default YarnConfigOptions.LOCALIZED_KEYTAB_PATH
        envs.put(
                YarnConfigKeys.LOCAL_KEYTAB_PATH,
                YarnConfigOptions.LOCALIZED_KEYTAB_PATH.defaultValue());

        Configuration configuration = new Configuration();
        YarnTaskExecutorRunner.setupAndModifyConfiguration(configuration, resourceDirPath, envs);

        // the SecurityContext is installed on TaskManager startup
        SecurityUtils.install(new SecurityConfiguration(configuration));

        final List<SecurityModule> modules = SecurityUtils.getInstalledModules();
        Optional<SecurityModule> moduleOpt =
                modules.stream().filter(module -> module instanceof HadoopModule).findFirst();

        if (moduleOpt.isPresent()) {
            HadoopModule hadoopModule = (HadoopModule) moduleOpt.get();
            assertThat(hadoopModule.getSecurityConfig().getPrincipal())
                    .isEqualTo("testuser1@domain");
            assertThat(hadoopModule.getSecurityConfig().getKeytab())
                    .isEqualTo(
                            new File(
                                            resourceDirPath,
                                            YarnConfigOptions.LOCALIZED_KEYTAB_PATH.defaultValue())
                                    .getAbsolutePath());
        } else {
            fail("Can not find HadoopModule!");
        }

        assertThat(configuration.get(SecurityOptions.KERBEROS_LOGIN_KEYTAB))
                .isEqualTo(
                        new File(
                                        resourceDirPath,
                                        YarnConfigOptions.LOCALIZED_KEYTAB_PATH.defaultValue())
                                .getAbsolutePath());
        assertThat(configuration.get(SecurityOptions.KERBEROS_LOGIN_PRINCIPAL))
                .isEqualTo("testuser1@domain");
    }