protected static NacosClient client(@Nullable String serviceName, @Nullable String groupName) {
        final NacosClientBuilder builder;
        if (serviceName != null) {
            builder = NacosClient.builder(nacosUri, serviceName);
        } else {
            builder = NacosClient.builder(nacosUri, NacosTestBase.serviceName);
        }

        if (groupName != null) {
            builder.groupName(groupName);
        }
        return builder.authorization(NACOS_AUTH_SECRET, NACOS_AUTH_SECRET)
                      .build();
    }
A helper class for testing with Nacos.
nacos/src/test/java/com/linecorp/armeria/internal/nacos/NacosTestBase.java