Spring cloud：服务调用-声明式客户端访问

环境

1. spring cloud Edgware.SR6
2. jdk 7
3. sts 4.6.0
4. mysql 5.7

背景

通过声明式客户端 openfeign 进行支付微服务的访问。

搭建步骤

只需要修改支付服务调用层，增加依赖就可以了。

支付服务调用层

只需要定义接口，不需要进行实现。

package jiangbo.springcloud.dao;

import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;

import jiangbo.springcloud.dao.dto.PaymentRequest;
import jiangbo.springcloud.dao.dto.PaymentResponse;

@FeignClient("payment")
public interface PaymentDao {

    @PostMapping("/payment")
    PaymentResponse payment(PaymentRequest paymentRequest);
}

启动类

package jiangbo.springcloud;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.netflix.feign.EnableFeignClients;

@SpringBootApplication
@EnableEurekaClient
@EnableFeignClients
public class JiangBoApplication {

    public static void main(String[] args) {

        SpringApplication.run(JiangBoApplication.class, args);
    }
}

pom.xml

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-parent</artifactId>
        <version>Edgware.SR6</version>
    </parent>

    <groupId>jiangbo.springcloud</groupId>
    <artifactId>12spring-cloud-order</artifactId>
    <version>1.0.0</version>
    <packaging>jar</packaging>

    <properties>
        <java.version>1.7</java.version>
    </properties>

    <dependencies>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>provided</scope>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

验证

使用 curl 命令访问订单微服务，查看返回，如果返回的订单已支付，则表示通过声明式客户端访问成功。

 curl -H "Content-Type: application/json" -X POST --data '{"name":"jiangbo11","amount":"8.99"}', http://localhost:4410/order/payment
{"id":12,"name":"jiangbo11","amount":"8.99","status":"PAID","createTime":1587304461000,"updateTime":1587304462000}   

默认也是具有负载均衡的。