远程调用常用有RestTemplate和Feign,底层均使用Ribbon实现负载均衡。简单样例,演示远程集群调用。
一、RestTemplate + Ribbon
访问方式:http://localhost:7903/condition/test,然后会执行以下访问:http://microservice-b/condition/self,如果microservice-b有多个节点,会按照负载均衡策略轮流访问。注意为顺利执行样例,microservice-b要实现/condition/self的mapping。
该例子无需额外添加spring-cloud-starter-netflix-ribbon依赖。
pom.xml
<?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>2.6.1</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.abcd</groupId>
<artifactId>SpringCloudServiceConsumer</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>SpringCloudServiceConsumer</name>
<description>SpringCloudServiceConsumer</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>2021.0.0</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>