spring cloud的入门级别的系统搭建

深藏阁楼爱情的钟 2022-06-06 12:52 52阅读 0赞

spring cloud是一套非常好的微服务架构解决方案，其原理和使用zookeeper及dubbo有些类似，将服务的生产者注册至服务中心，消费者去服务中心订阅该消费者，并进行消费，原理图如下：  
![这里写图片描述][SouthEast]

**系统背景：**客户调用A系统获取数据，A系统需要将基本数据去B系统计算结果。

--------------------

## 注册服务中心的搭建 ##

1.  导入依赖（spring cloud是基于spring boot的，所以需要导入spring boot的依赖）：

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.RELEASE</version>
    </parent>
    
    
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.SR3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    
    <dependencies>
        
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
    </dependencies>
    
    <build>
        <finalName>${project.artifactId}</finalName>
        <plugins>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

2.配置文件编写（application.yml）：

server:
      port: 6868 #服务端口
    
    eureka:
      client:
        registerWithEureka: false #是否将自己注册到Eureka服务中，本身就是所有无需注册
        fetchRegistry: false #是否从Eureka中获取注册信息
        serviceUrl: #Eureka客户端与Eureka服务端进行交互的地址
          defaultZone: http://cloud:cloud@127.0.0.1:${server.port}/eureka/
    
    security: 
      basic:  
        enable: true #开启基于HTTP basic的认证
      user: #配置用户的账号信息
        name: cloud
        password: cloud

3.启动类：

@EnableEurekaServer //申明这是一个Eureka服务
    @SpringBootApplication
    public class EurekaServer { 
    
        public static void main(String[] args) {
            SpringApplication.run(EurekaServer.class, args);
        }
    
    }

启动该服务，登录127.0.0.1:6868,进入注册服务中心控制台：  
![这里写图片描述][SouthEast 1]  
到此，注册中心就搭建完成，但是还没有服务注册。

--------------------

## 计算系统的搭建 ##

1.导入依赖

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.RELEASE</version>
    </parent>
    
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.SR3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
        </dependency>
    </dependencies>
    
    <build>
        <finalName>${project.artifactId}</finalName>
        <plugins>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

2.配置文件的编写

server:
      port: 8082
    
    spring: 
      application:  
        name: com-spring-caclulate #指定服务名
    
    eureka:
      client:
        registerWithEureka: true #是否将自己注册到Eureka服务中，默认为true
        fetchRegistry: true #是否从Eureka中获取注册信息，默认为true
        serviceUrl: #Eureka客户端与Eureka服务端进行交互的地址
          defaultZone: http://cloud:cloud@127.0.0.1:6868/eureka/
      instance: 
        prefer-ip-address: true #将自己的ip地址注册到Eureka服务中

3.启动类

@EnableDiscoveryClient//申请成为注册服务中心的客户端
    @SpringBootApplication //申明这是一个Spring Boot项目
    public class CacluApplication { 
    
        public static void main(String[] args) {
            SpringApplication.run(ItemApplication.class, args);
        }
    
    }

4.功能代码（系统中的业务代码）

@RestController
    public class CacluController { 
    
        /** * 对外提供接口服务，计算数据 * * @param num * @return */
        //@RequestMapping(method = RequestMethod.GET)
        @GetMapping(value = "caclu/{num}")
        public Integer caclulate(@PathVariable("num") Integer num) {
            return num*10;
        }
    }

启动商品系统，再次登录注册服务中心，我们发现该服务已经注册了。  
![这里写图片描述][SouthEast 2]

--------------------

## 消费系统的搭建 ##

1.导入依赖

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.4.RELEASE</version>
    </parent>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Dalston.SR3</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
    
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>com.squareup.okhttp3</groupId>
            <artifactId>okhttp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-eureka-server</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>com.fasterxml.jackson.dataformat</groupId>
                    <artifactId>jackson-dataformat-xml</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    
    <build>
        <finalName>${project.artifactId}</finalName>
        <plugins>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
            
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>

2.配置文件

server:
      port: 8083
    
    eureka:
      client:
        registerWithEureka: false #是否将自己注册到Eureka服务中，默认为true
        fetchRegistry: true #是否从Eureka中获取注册信息，默认为true
        serviceUrl: #Eureka客户端与Eureka服务端进行交互的地址
          defaultZone: http://cloud:cloud@127.0.0.1:6868/eureka/

3.启动类

@EnableDiscoveryClient
    @SpringBootApplication
    public class OrderApplication { 
    
        @Bean // 向Spring容器中定义RestTemplate对象
        public RestTemplate restTemplate(){
            return new RestTemplate(new OkHttp3ClientHttpRequestFactory());
    
        }
    
        public static void main(String[] args) {
            SpringApplication.run(OrderApplication.class, args);
        }
    }

4.业务代码

@RestController
    public class OrderController { 
    
        @Autowired
        private RestTemplate restTemplate;
        @Autowired
        private DiscoveryClient discoveryClient;
    
    
        @GetMapping(value = "query/result")
        public Integer caclulate() {
            String serviceId = "com-spring-caclulate";
            List<ServiceInstance> instances = this.discoveryClient.getInstances(serviceId);
            if(instances.isEmpty()){
                return null;
            }
            ServiceInstance serviceInstance = instances.get(0);
            String url = serviceInstance.getHost() + ":" + serviceInstance.getPort();
            return this.restTemplate.getForObject("http://" + url + "/caclu/1", Integer.class);
        }
    }

启动服务，并访问接口，我们调用时num为1，计算结果为10。

[SouthEast]: /images/20220606/f2a70215d7ac4f989f8e73c684cc4dc2.png
[SouthEast 1]: /images/20220606/86bd991a908c4bcbab5f72d14c5228b8.png
[SouthEast 2]: /images/20220606/e72d7ae41d8c462ebc258e82b08181e6.png