[ISSUE mxsm#941]📝Update client README.md✨ (mxsm#942)

rocketmq-client/README.md

@@ -2,4 +2,154 @@
 
 ## Overview
 
-This project is the Rust implementation of Apache RocketMQ client. It is based on the RocketMQ Java client
+This project is the Rust implementation of Apache RocketMQ client. It is based on the RocketMQ Java client
+
+## How to send message
+
+First, start the RocketMQ NameServer and Broker services.
+
+- [**Send a single message**](#Send a single message)
+
+- [**Send batch messages**](#Send batch messages)
+
+- [**Send RPC messages**](#Send RPC messages)
+
+[**For more examples, you can check here**](https://github.com/mxsm/rocketmq-rust/tree/main/rocketmq-client/examples)
+
+### Send a single message
+
+```rust
+use rocketmq_client::producer::default_mq_producer::DefaultMQProducer;
+use rocketmq_client::producer::mq_producer::MQProducer;
+use rocketmq_client::Result;
+use rocketmq_common::common::message::message_single::Message;
+use rocketmq_rust::rocketmq;
+
+pub const MESSAGE_COUNT: usize = 1;
+pub const PRODUCER_GROUP: &str = "please_rename_unique_group_name";
+pub const DEFAULT_NAMESRVADDR: &str = "127.0.0.1:9876";
+pub const TOPIC: &str = "TopicTest";
+pub const TAG: &str = "TagA";
+
+#[rocketmq::main]
+pub async fn main() -> Result<()> {
+    //init logger
+    rocketmq_common::log::init_logger();
+
+    // create a producer builder with default configuration
+    let builder = DefaultMQProducer::builder();
+
+    let mut producer = builder
+        .producer_group(PRODUCER_GROUP.to_string())
+        .name_server_addr(DEFAULT_NAMESRVADDR.to_string())
+        .build();
+
+    producer.start().await?;
+
+    for _ in 0..10 {
+        let message = Message::with_tags(TOPIC, TAG, "Hello RocketMQ".as_bytes());
+
+        let send_result = producer.send_with_timeout(message, 2000).await?;
+        println!("send result: {}", send_result);
+    }
+    producer.shutdown().await;
+
+    Ok(())
+}
+```
+
+### Send batch messages
+
+```rust
+use rocketmq_client::producer::default_mq_producer::DefaultMQProducer;
+use rocketmq_client::producer::mq_producer::MQProducer;
+use rocketmq_common::common::message::message_single::Message;
+use rocketmq_rust::rocketmq;
+
+pub const PRODUCER_GROUP: &str = "BatchProducerGroupName";
+pub const DEFAULT_NAMESRVADDR: &str = "127.0.0.1:9876";
+pub const TOPIC: &str = "TopicTest";
+pub const TAG: &str = "TagA";
+
+#[rocketmq::main]
+pub async fn main() -> rocketmq_client::Result<()> {
+    //init logger
+    rocketmq_common::log::init_logger();
+
+    // create a producer builder with default configuration
+    let builder = DefaultMQProducer::builder();
+
+    let mut producer = builder
+        .producer_group(PRODUCER_GROUP.to_string())
+        .name_server_addr(DEFAULT_NAMESRVADDR.to_string())
+        .build();
+    producer.start().await?;
+
+    let mut messages = Vec::new();
+    messages.push(Message::with_keys(
+        TOPIC,
+        TAG,
+        "OrderID001",
+        "Hello world 0".as_bytes(),
+    ));
+    messages.push(Message::with_keys(
+        TOPIC,
+        TAG,
+        "OrderID002",
+        "Hello world 1".as_bytes(),
+    ));
+    messages.push(Message::with_keys(
+        TOPIC,
+        TAG,
+        "OrderID003",
+        "Hello world 2".as_bytes(),
+    ));
+    let send_result = producer.send_batch(messages).await?;
+    println!("send result: {}", send_result);
+    Ok(())
+}
+```
+
+### Send RPC messages
+
+```rust
+use rocketmq_client::producer::default_mq_producer::DefaultMQProducer;
+use rocketmq_client::producer::mq_producer::MQProducer;
+use rocketmq_client::Result;
+use rocketmq_common::common::message::message_single::Message;
+use rocketmq_rust::rocketmq;
+
+pub const MESSAGE_COUNT: usize = 1;
+pub const PRODUCER_GROUP: &str = "please_rename_unique_group_name";
+pub const DEFAULT_NAMESRVADDR: &str = "127.0.0.1:9876";
+pub const TOPIC: &str = "RequestTopic";
+pub const TAG: &str = "TagA";
+
+#[rocketmq::main]
+pub async fn main() -> Result<()> {
+    //init logger
+    rocketmq_common::log::init_logger();
+
+    // create a producer builder with default configuration
+    let builder = DefaultMQProducer::builder();
+
+    let mut producer = builder
+        .producer_group(PRODUCER_GROUP.to_string())
+        .name_server_addr(DEFAULT_NAMESRVADDR.to_string())
+        .build();
+
+    producer.start().await?;
+    let ttl = 3000;
+    let message = producer
+        .request(
+            Message::with_tags(TOPIC, "", "Hello RocketMQ".as_bytes()),
+            ttl,
+        )
+        .await?;
+    println!("send result: {:?}", message);
+    producer.shutdown().await;
+
+    Ok(())
+}
+```
+