spring-clound基础开发

一、使用openfeig调用远程另外一个服务接口

• 1、创建一个spring boot工程,并且创建2个模块来当微服务模块

• 2、分别配置2个模块的启动文件

• 3、分别两个模块下创建一个测试的控制器

• 4、在项目的根目录的pom.xml中添加spring-cloud配置

  <properties>
      <java.version>1.8java.version>
      <spring-cloud.version>2021.0.8spring-cloud.version>
  properties>
  

  <dependencyManagement>
      <dependencies>
          <dependency>
              <groupId>org.springframework.cloudgroupId>
              <artifactId>spring-cloud-dependenciesartifactId>
              <version>${spring-cloud.version}version>
              <type>pomtype>
              <scope>importscope>
          dependency>
      dependencies>
  dependencyManagement>
  

• 5、在需要调用别的服务的项目中添加依赖

  
  <dependency>
      <groupId>org.springframework.cloudgroupId>
      <artifactId>spring-cloud-starter-openfeignartifactId>
  dependency>
  <dependency>
      <groupId>org.springframework.cloudgroupId>
      <artifactId>spring-cloud-loadbalancerartifactId>
  dependency>
  

• 6、在需要调用别的 服务的项目中创建一个文件夹feign，里面创建一个文件SystemFeignHello.java的接口

  package com.example.feign;
  
  import org.springframework.cloud.openfeign.FeignClient;
  import org.springframework.web.bind.annotation.GetMapping;
  
  @FeignClient(name = "system", url = "http://localhost:9001/system")
  public interface SystemFeignHello {
      /**
       * 别的地方调用hell1方法的时候就会调用http://localhost:9001/system/hello路由
       * @return
       */
      @GetMapping("hello")
      String hello1();
  }
  

• 7、测试调用另外一个服务的接口

  package com.example.controller;
  
  import com.example.feign.SystemFeignHello;
  import org.springframework.web.bind.annotation.GetMapping;
  import org.springframework.web.bind.annotation.RestController;
  
  import javax.annotation.Resource;
  
  @RestController
  public class HelloController {
  
      @Resource
      SystemFeignHello systemFeignHello;
  
      @GetMapping("hello")
      public String hello() {
          return "File Hello";
      }
  
  
      @GetMapping("systemHello")
      public String getHello() {
          String helloResult = this.systemFeignHello.hello1();
          System.out.println(helloResult+"返回数据");
          return helloResult;
      }
  }
  

• 8、在调用服务的启动类上加上扫描注解

  package com.example;
  
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  import org.springframework.cloud.openfeign.EnableFeignClients;
  
  @SpringBootApplication
  @EnableFeignClients("com.example.feign")
  public class FileApplication {
  
      public static void main(String[] args) {
          SpringApplication.run(FileApplication.class, args);
      }
  
  }
  

• 9、网页上测试调用接口

• 10、system项目中接口如下,和普通接口没任何区别

  package com.example.controller;
  
  import org.springframework.web.bind.annotation.GetMapping;
  import org.springframework.web.bind.annotation.RestController;
  
  @RestController
  public class HelloController {
  
      @GetMapping("hello")
      public String hello() {
          return "System Hello11";
      }
  }
  

二、使用eureka来服务端配置

• 1、eureka分为服务端和客户端，需要在项目中先创建一个eureka的服务段,在子项目中使用客户端的方式连接

• 2、创建一个eureka模块来做服务端

• 3、在eureka模块中添加依赖包

  <dependencies>
      <dependency>
          <groupId>org.springframework.cloudgroupId>
          <artifactId>spring-cloud-starter-netflix-eureka-serverartifactId>
      dependency>
  dependencies>
  

• 4、配置文件中基本配置

  spring.application.name=eureka
  server.port=8761
  eureka.client.fetch-registry=false
  eureka.client.register-with-eureka=false
  

• 5、在启动类上添加注解

  package com.example;
  
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
  
  @SpringBootApplication
  @EnableEurekaServer
  public class EurekaApplication {
  
      public static void main(String[] args) {
          SpringApplication.run(EurekaApplication.class, args);
      }
  
  }
  

• 6、直接在浏览器上输入http://localhost:8761/如下就表示配置成功

  

三、客户端配置

• 1、引入依赖包

  
  <dependency>
      <groupId>org.springframework.cloudgroupId>
      <artifactId>spring-cloud-starter-netflix-eureka-clientartifactId>
  dependency>
  

• 2、在配置文件中添加

  eurec.client.server-url.defaultZone=http://localhost:8761/eureka/
  

• 3、在启动文件中添加

  @SpringBootApplication
  @EnableEurekaClient
  public class SystemApplication {
  
      public static void main(String[] args) {
          SpringApplication.run(SystemApplication.class, args);
      }
  
  }
  

• 4、刷新浏览器查看服务是否已经注册成功

  

四、网关的配置

• 1、创建一个网关模块

• 2、在网关中引入依赖包

  <dependencies>
      
      <dependency>
          <groupId>org.springframework.cloudgroupId>
          <artifactId>spring-cloud-starter-gatewayartifactId>
      dependency>
      
      <dependency>
          <groupId>org.springframework.cloudgroupId>
          <artifactId>spring-cloud-starter-netflix-eureka-clientartifactId>
      dependency>
  dependencies>
  

• 3、修改配置文件

  server.port=8000
  spring.application.name=gateway
  server.servlet.context-path=/gateway
  spring.main.web-application-type=reactive 
  eurec.client.server-url.defaultZone=http://localhost:8761/eureka/
  
  
  
  # 注册一个服务
  spring.cloud.gateway.routes[0].id=system
  spring.cloud.gateway.routes[0].uri.=http://localhost:9001
  spring.cloud.gateway.routes[0].predicates[0].name=Path
  spring.cloud.gateway.routes[0].predicates[0].args[0]=/system/**
  # 注册一个服务
  spring.cloud.gateway.routes[1].id=file
  spring.cloud.gateway.routes[1].uri.=http://localhost:9000
  spring.cloud.gateway.routes[1].predicates[0].name=Path
  spring.cloud.gateway.routes[1].predicates[0].args[0]=/file/**
  

• 4、启动文件

  package com.example;
  
  import org.springframework.boot.SpringApplication;
  import org.springframework.boot.autoconfigure.SpringBootApplication;
  import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
  
  @SpringBootApplication
  @EnableEurekaClient
  public class GatewayApplication {
  
      public static void main(String[] args) {
          SpringApplication.run(GatewayApplication.class, args);
      }
  
  }
  

• 5、使用网关的地址直接访问别的路由http://localhost:8000/system/hello