搭建springcloud feign使用案例

àì夳堔傛蜴生んèń 2023-03-13 02:33 2阅读 0赞

### 本文介绍搭建微服务的具体配置以及feign的使用，案例中有三个角色：服务注册中心、服务提供者、服务消费者。 ###

### **服务注册中心具体配置** ###

**Pom依赖如下**

application.properties配置

server.port=8000
    eureka.instance.hostname=localhost
    #在默认设置下， 该服务注册中心也会将自己作为客户端来尝试注册它自己，所以我们需要禁用它的客户端注册行为
    eureka.client.registerWithEureka=false
    eureka.client.fetchRegistry=false
    eureka.client.serviceUrl.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/

启动类上添加

@EnableEurekaServer

### **服务提供者具体配置** ###

**pom依赖如下**

application.properties配置

server.port=8081
    eureka.client.serviceUrl.defaultZone=http://localhost:8000/eureka/
    #服务名称
    spring.application.name=provider1

启动类上添加

@EnableEurekaClient
    @EnableDiscoveryClient
    @EnableFeignClients

创建实体类

public class Student {
        private String name;
    
        private String id;
    
        public Student() {
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public String getId() {
            return id;
        }
    
        public void setId(String id) {
            this.id = id;
        }
    
        @Override
        public String toString() {
            return "Student{" +
                    "name='" + name + '\'' +
                    ", id='" + id + '\'' +
                    '}';
        }
    }

创建接口

public interface StudentService {
    
        String getAllStudent();
    
    }

创建接口实现类

import com.cncbox.pojo.Student;
    import org.springframework.stereotype.Service;
    import java.util.ArrayList;
    import java.util.List;
    @Service
    public class StudentServiceImp implements StudentService {
            private static List<Student> studentList = new ArrayList<>();
    
            public String getAllStudent() {
    
                return studentList.toString();
            }
    
    }

Controller

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController
    public class StudentController{
        @Autowired
        private StudentService studentService;
    
        @GetMapping(value = "/myfeign")
        @ResponseBody
        public String getAllStudent() {
            return studentService.getAllStudent();
        }
    }

### **服务消费者具体配置** ###

**pom依赖如下**

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.2.7.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.cncbox</groupId>
        <artifactId>springcloud-client</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>springcloud-client</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
            <spring-cloud.version>Hoxton.SR4</spring-cloud.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
                <exclusions>
                    <exclusion>
                        <groupId>org.junit.vintage</groupId>
                        <artifactId>junit-vintage-engine</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-openfeign</artifactId>
            </dependency>
            <dependency>
                <groupId>net.minidev</groupId>
                <artifactId>json-smart</artifactId>
                <version>2.3</version>
                <scope>compile</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>5.2.6.RELEASE</version>
                <scope>compile</scope>
            </dependency>
        </dependencies>
    
        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-dependencies</artifactId>
                    <version>${spring-cloud.version}</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
            </dependencies>
        </dependencyManagement>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

application.properties配置

server.port=8084
    spring.application.name=consumer-service
    eureka.instance.prefer-ip-address=true
    # 配置注册中心地址
    eureka.client.serviceUrl.defaultZone=http://localhost:8000/eureka/

启动类上添加

@EnableDiscoveryClient
    @EnableFeignClients

创建实体类

创建接口，要注意name为服务提供者向注册中心注册的实例名,GetMapping要与服务提供者的方法路径一致

import org.springframework.cloud.openfeign.FeignClient;
    import org.springframework.web.bind.annotation.GetMapping;
    
    //name为服务提供者向注册中心注册的实例名
    @FeignClient(name = "provider1")
        public interface StudentService {
    
            /**
             * 获取所有学生列表
             * @return
             */
            @GetMapping(value = "/myfeign")
            String getAllStudent();
    }

Controller

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.RestController;
    
    @RestController
    public class StudentController {
    
        @Autowired
        private StudentService studentService;
    
        @GetMapping(value = "/myfeign")
        public String getAllStudent() {
            return studentService.getAllStudent();
        }
        
    }

分别启动服务注册中心、服务提供者、服务消费者

访问[http://localhost:8084/myfeign][http_localhost_8084_myfeign]

[http_localhost_8084_myfeign]: http://localhost:8084/myfeign