Spring Cloud (Spring Cloud Stream)解析

执行脚本目录 /bin

windows 在其单独的目录

快速上手

下载并且解压kafka压缩包

运行服务

以Windows为例，首先打开cmd：

1.  启动zookeeper：

bin\windows\zookeeper-server-start.bat config\zookeeper.properties

2.  启动kafka：

bin\windows\kafka-server-start.bat config\server.properties

创建主题topic

bin\windows\kafka-topics.bat --create --bootstrap-server localhost:9092 --replication-factor 1 --partitions 1 --topic cloud

cloud

生产者：发送消息

\bin\windows>kafka-console-producer.bat --broker-list localhost:9092 --topic cloud

>hello

消费者：接收消息

\bin\windows>kafka-console-consumer.bat --bootstrap-server localhost:9092 --topic cloud --from-beginning

hello

同类产品比较

ActiveMQ：JMS（Java Message Service）规范实现

RabbitMQ：AMQP（Advanced Message Queue Protocol）规范实现

Kafka：并非某种规范实现，它的灵活和性能相对是优势

Spring Kafka

import java.util.Properties;

import java.util.concurrent.ExecutionException;

import java.util.concurrent.Future;

import org.apache.kafka.clients.producer.KafkaProducer;

import org.apache.kafka.clients.producer.ProducerRecord;

import org.apache.kafka.clients.producer.RecordMetadata;

import org.apache.kafka.common.serialization.StringSerializer;

public class TestKafka{

public static void main(String[] args) throws ExecutionException, InterruptedException {

Properties properties = new Properties();

properties.setProperty("bootstrap.servers", "localhost:9092");

properties.setProperty("key.serializer", StringSerializer.class.getName());

properties.setProperty("value.serializer", StringSerializer.class.getName());

// 创建 Kafka Producer

KafkaProducer<String, String> kafkaProducer = new KafkaProducer(properties);

// 创建Kafka消息 = ProducerRecord

String topic = "cloud";

Integer partition = 0;

Long timestamp = System.currentTimeMillis();

String key = "message-key";

String value = "how are you!";

ProducerRecord<String, String> record = new ProducerRecord<String, String>(topic, partition, timestamp, key, value);

// 发送kafka消息

Future<RecordMetadata> metadataFuture = kafkaProducer.send(record);

// 强制执行

metadataFuture.get();

}

}

设计模式

Spring社区对data（Spring-data）操作，有一个基本的模式，Template模式：

JDBC：JdbcTemplate

Redis：RedisTemplate

Kafka：KafkaTemplate

JMS：JmsTemplate

Rest：RestTemplate

XXXTemplate一定实现XXXOpeations

KafkaTemplate implements KafkaOpeations

Maven依赖

<dependency>

<groupId>org.springframework.kafka</groupId>

<artifactId>spring-kafka</artifactId>

</dependency>

自动装配器： 外汇返佣http://www.fx61.com/，KafkaAutoConfiguration

其中KafkaTemplate会被自动装配：

import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;

import org.springframework.boot.autoconfigure.kafka.KafkaProperties;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

import org.springframework.kafka.core.KafkaTemplate;

import org.springframework.kafka.core.ProducerFactory;

import org.springframework.kafka.support.ProducerListener;

@Configuration

public class KafkaAutoConfiguration {

private final KafkaProperties properties;

public KafkaAutoConfiguration(KafkaProperties properties) {

this.properties = properties;

}

@Bean

@ConditionalOnMissingBean(KafkaTemplate.class)

public KafkaTemplate<?,?> kafkaTemplate(ProducerFactory<Object,Object> kafkaProducerFactory,

ProducerListener<Object,Object> kafkaProducerListener){

KafkaTemplate<Object,Object> kafkaTemplate = new KafkaTemplate<Object,Object>(kafkaProducerFactory);

kafkaTemplate.setProducerListener(kafkaProducerListener);

kafkaTemplate.setDefaultTopic(this.properties.getTemplate().getDefaultTopic());

return kafkaTemplate;

}

}

创建生产者

增加生产者配置

application.properties

全局配置：

### Kafka生产者配置

spring.kafka.producer.bootstrapServers = localhost:9092

### Kafka生产者配置

# spring.kafka.producer.bootstrapServers = localhost:9092

spring.kafka.producer.keySerializer = org.apache.kafka.common.serialization.StringSerializer

spring.kafka.producer.valueSerializer = org.apache.kafka.common.serialization.StringSerializer

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.kafka.core.KafkaTemplate;

import org.springframework.web.bind.annotation.PostMapping;

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.RestController;

@RestController

public class KafkaProducerController {

private final KafkaTemplate<String, String> kafkaTemplate;

private final String topic;

@Autowired

public KafkaProducerController(KafkaTemplate<String, String> kafkaTemplate, @Value("${kafka.topic}") String topic) {

this.kafkaTemplate = kafkaTemplate;

this.topic = topic;

}

@PostMapping("/message/send")

public Boolean sendMessage(@RequestParam(required=false)String message) {

kafkaTemplate.send(topic, message);

return true;

}

}

创建消费者

增加消费者配置

### Kafka消费者配置

spring.kafka.consumer.groupId = cloud-1

spring.kafka.consumer.keyDeserializer = org.apache.kafka.common.serialization.StringDeserializer

spring.kafka.consumer.valueDeserializer = org.apache.kafka.common.serialization.StringDeserializer

import org.springframework.kafka.annotation.KafkaListener;

import org.springframework.stereotype.Component;

@Component

public class KafkaConsumerListener {

@KafkaListener(topics = "${kafka.topic}")

public void onMessage(String message) {

System.out.print("kafka 消费者监听器，接收到消息：" + message);

}

}

端口信息

spring-cloud-zuul:7070

person-client:8080

person-service:9090

Eureka Server:12345

ZipKin Server:23456

Config Server:10001

服务启动顺序

zipkin Server

Eureka Server

spring-cloud-config-server

person-server

person-client

spring-cloud-zuul

spring-cloud-sleuth

spring-cloud-sleuth-demo改造

增加Eureka客户端依赖

<dependency>

<groupId>org.springframework.cloud</groupId>

<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>

</dependency>

配置调整

spring.application.name = spring-cloud-sleuth

server.port = 6060

spring.zipkin.base-url=http://localhost:23456/

eureka.client.serviceUrl.defaultZone=http://localhost:12345/eureka

调整代码链接：spring-cloud-zuul

完整调用链路

spring-cloud-sleuth →   spring-cloud-zuul →   person-client →   person-service

@RestController

public class TestLoggerController {

final static Logger LOGGER = LoggerFactory.getLogger(TestLoggerController.class);

@Autowired

@Qualifier("restTemplate")

private RestTemplate restTemplate;

@GetMapping("/send")

public void send() {

LOGGER.info(" 欢迎欢迎！");

}

@GetMapping("/to/zuul/pseron-clint/findall")

public Object findall() {

LOGGER.info("TestLoggerController#findall()");

return restTemplate.getForObject("http://spring-cloud-zuul/person-client/person/findall", Object.class);

}