chore: add an example lazy_app (#239)

Cargo.toml

@@ -84,3 +84,7 @@ mockall = { version = "0.11" }
 [[example]]
 name = "simple_app"
 path = "examples/simple_app.rs"
+
+[[example]]
+name = "lazy_app"
+path = "examples/lazy_app.rs"

examples/lazy_app.rs

@@ -0,0 +1,134 @@
+use nacos_sdk::api::config::{
+    ConfigChangeListener, ConfigResponse, ConfigService, ConfigServiceBuilder,
+};
+use nacos_sdk::api::constants;
+use nacos_sdk::api::naming::{
+    NamingChangeEvent, NamingEventListener, NamingService, NamingServiceBuilder, ServiceInstance,
+};
+use nacos_sdk::api::props::ClientProps;
+
+use std::sync::LazyLock;
+
+static CLIENT_PROPS: LazyLock<ClientProps> = LazyLock::new(|| {
+    ClientProps::new()
+        .server_addr(constants::DEFAULT_SERVER_ADDR)
+        // .remote_grpc_port(9838)
+        // Attention! "public" is "", it is recommended to customize the namespace with clear meaning.
+        .namespace("")
+        .app_name("lazy_app")
+        .auth_username("nacos") // TODO You can choose not to enable auth
+        .auth_password("nacos") // TODO You can choose not to enable auth
+});
+
+// 请注意！一般情况下，应用下仅需一个 Config 客户端，而且需要长期持有直至应用停止。
+// 因为它内部会初始化与服务端的长链接，后续的数据交互及变更订阅，都是实时地通过长链接告知客户端的。
+static CONFIG_SERVICE: LazyLock<Box<dyn ConfigService>> = LazyLock::new(|| {
+    let config_service = ConfigServiceBuilder::new(CLIENT_PROPS.clone())
+        .enable_auth_plugin_http() // TODO You can choose not to enable auth
+        .build()
+        .unwrap();
+    Box::new(config_service)
+});
+
+// 请注意！一般情况下，应用下仅需一个 Naming 客户端，而且需要长期持有直至应用停止。
+// 因为它内部会初始化与服务端的长链接，后续的数据交互及变更订阅，都是实时地通过长链接告知客户端的。
+static NAMING_SERVICE: LazyLock<Box<dyn NamingService>> = LazyLock::new(|| {
+    let naming_service = NamingServiceBuilder::new(CLIENT_PROPS.clone())
+        .enable_auth_plugin_http() // TODO You can choose not to enable auth
+        .build()
+        .unwrap();
+    Box::new(naming_service)
+});
+
+/// enable https auth run with command:
+/// cargo run --example lazy_app --features default,tls
+#[tokio::main]
+async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    tracing_subscriber::fmt()
+        // all spans/events with a level higher than TRACE (e.g, info, warn, etc.)
+        // will be written to stdout.
+        .with_max_level(tracing::Level::INFO)
+        .with_thread_names(true)
+        .with_thread_ids(true)
+        // sets this to be the default, global collector for this application.
+        .init();
+
+    // ----------  Config  -------------
+    let config_resp = CONFIG_SERVICE
+        .get_config("todo-data-id".to_string(), "LOVE".to_string())
+        .await;
+    match config_resp {
+        Ok(config_resp) => tracing::info!("get the config {}", config_resp),
+        Err(err) => tracing::error!("get the config {:?}", err),
+    }
+
+    let _listen = CONFIG_SERVICE
+        .add_listener(
+            "todo-data-id".to_string(),
+            "LOVE".to_string(),
+            std::sync::Arc::new(SimpleConfigChangeListener {}),
+        )
+        .await;
+    match _listen {
+        Ok(_) => tracing::info!("listening the config success"),
+        Err(err) => tracing::error!("listen config error {:?}", err),
+    }
+
+    // ----------  Naming  -------------
+    let listener = std::sync::Arc::new(SimpleInstanceChangeListener);
+    let _subscribe_ret = NAMING_SERVICE
+        .subscribe(
+            "test-service".to_string(),
+            Some(constants::DEFAULT_GROUP.to_string()),
+            Vec::default(),
+            listener,
+        )
+        .await;
+
+    let service_instance1 = ServiceInstance {
+        ip: "127.0.0.1".to_string(),
+        port: 9090,
+        ..Default::default()
+    };
+    let _register_instance_ret = NAMING_SERVICE
+        .batch_register_instance(
+            "test-service".to_string(),
+            Some(constants::DEFAULT_GROUP.to_string()),
+            vec![service_instance1],
+        )
+        .await;
+    tokio::time::sleep(tokio::time::Duration::from_millis(666)).await;
+
+    let instances_ret = NAMING_SERVICE
+        .get_all_instances(
+            "test-service".to_string(),
+            Some(constants::DEFAULT_GROUP.to_string()),
+            Vec::default(),
+            false,
+        )
+        .await;
+    match instances_ret {
+        Ok(instances) => tracing::info!("get_all_instances {:?}", instances),
+        Err(err) => tracing::error!("naming get_all_instances error {:?}", err),
+    }
+
+    tokio::time::sleep(tokio::time::Duration::from_secs(300)).await;
+
+    Ok(())
+}
+
+struct SimpleConfigChangeListener;
+
+impl ConfigChangeListener for SimpleConfigChangeListener {
+    fn notify(&self, config_resp: ConfigResponse) {
+        tracing::info!("listen the config={}", config_resp);
+    }
+}
+
+pub struct SimpleInstanceChangeListener;
+
+impl NamingEventListener for SimpleInstanceChangeListener {
+    fn event(&self, event: std::sync::Arc<NamingChangeEvent>) {
+        tracing::info!("subscriber notify: {:?}", event);
+    }
+}