-
spring-cloud-square开发实战(三种类型全覆盖)
本篇概览
-
前文《五分钟搞懂spring-cloud-square》详细介绍了什么是spring-cloud-square，以及三种实现类型的详细概念，爱动手的您已迫不及待想编码体验spring-cloud-square了，本篇咱们就来畅快实战，体验这个spring官方带给我们的smart client
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如标题所述，接下里咱们会将spring-cloud-square提供的三种client都编码体验，总的来说本篇由以下内容构成：
- 新建maven工程，名为spring-cloud-square-tutorials，这是本篇所有应用的父工程，库版本在此工程中统一管理；
- 创建子工程eureka，作为注册中心
- 创建子工程client，放一些公用的数据结构
- 创建子工程provider，身份是服务提供者，接下来的三个用到spring-cloud-square的子工程，都调用provider的服务
- 创建子工程consumer-okhttp，基于spring-cloud-square的okhttp能力做远程调用
- 创建子工程consumer-retrofit-okhttp，基于spring-cloud-square的retrofit + okhttp能力做远程调用
- 创建子工程consumer-retrofit-webflux，基于spring-cloud-square的retrofit + webflux能力做远程调用
- 上述几个服务的关系如下图：
如何验证
- 代码写完之后，如何验证功能是否符合预期呢？本篇采用单元测试的方式，consumer-okhttp、consumer-retrofit-okhttp、consumer-retrofit-webflux这三个子工程都有自己的单元测试代码，执行通过就意味着代码功能符合预期了
源码下载
- 本篇实战中的完整源码可在GitHub下载到，地址和链接信息如下表所示(https://github.com/zq2599/blog_demos)：
| 名称 | 链接 | 备注 |
|---|---|---|
| 项目主页 | https://github.com/zq2599/blog_demos | 该项目在GitHub上的主页 |
| git仓库地址(https) | https://github.com/zq2599/blog_demos.git | 该项目源码的仓库地址，https协议 |
| git仓库地址(ssh) | git@github.com:zq2599/blog_demos.git | 该项目源码的仓库地址，ssh协议 |
-
这个git项目中有多个文件夹，本篇的源码在spring-cloud-square-tutorials文件夹下，如下图红框所示：
版本信息
- 本篇实战涉及到的主要版本情况如下：
- JDK：1.8.0_291
- IDEA：2021.1.3 (Ultimate Edition)
- maven：3.8.1
- 操作系统：win10 64位
- springboot：2.4.4
- spring-cloud：2020.0.2
- spring-cloud-square：0.4.0-SNAPSHOT
父工程spring-cloud-square-tutorials
- 父工程名为spring-cloud-square-tutorials，其pom.xml如下，除了依赖库的版本在此统一管理，还要注意的是两个仓库的引入（https://repo.spring.io/snapshot和https://repo.spring.io/milestone），引入它们是因为spring-cloud-square还在孵化阶段，没有发布到maven中央仓库：
<?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 http://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>2.4.4</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.bolingcavalry</groupId>
<artifactId>spring-cloud-square-tutorials</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<maven.compiler.source>8</maven.compiler.source>
<maven.compiler.target>8</maven.compiler.target>
<java.version>1.8</java.version>
<spring-cloud.version>2020.0.2</spring-cloud.version>
<square.dependency.version>0.4.0-SNAPSHOT</square.dependency.version>
</properties>
<packaging>pom</packaging>
<description>Demo project for Spring Cloud Square Retrofit Web</description>
<modules>
<module>provider</module>
<module>eureka</module>
<module>consumer-okhttp</module>
<module>client</module>
<module>consumer-retrofit-okhttp</module>
<module>consumer-retrofit-webflux</module>
</modules>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>3.14.9</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.7</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.16</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-okhttp</artifactId>
<version>${square.dependency.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-retrofit</artifactId>
<version>${square.dependency.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
<version>${square.dependency.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-retrofit-webclient</artifactId>
<version>${square.dependency.version}</version>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<!--skip deploy (this is just a test module) -->
<artifactId>maven-deploy-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories>
</project>
注册中心eureka
- eureka应用并没有什么特别之处，pom.xml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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>spring-cloud-square-tutorials</artifactId>
<groupId>com.bolingcavalry</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>eureka</artifactId>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<start-class>com.bolingcavalry.eureka.EurekaApplication</start-class>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<!-- <version>Finchley.BUILD-SNAPSHOT</version>-->
<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>
<!-- defined in spring-cloud-starter-parent pom (as documentation hint),
but needs to be repeated here -->
<configuration>
<requiresUnpack>
<dependency>
<groupId>com.netflix.eureka</groupId>
<artifactId>eureka-core</artifactId>
</dependency>
<dependency>
<groupId>com.netflix.eureka</groupId>
<artifactId>eureka-client</artifactId>
</dependency>
</requiresUnpack>
</configuration>
</plugin>
<plugin>
<!--skip deploy (this is just a test module) -->
<artifactId>maven-deploy-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
</plugins>
</build>
</project>
- 中规中矩的配置文件application.yml，端口是8761，后面的应用也要保持一致：
server:
port: 8761
spring:
application:
name: eureka
eureka:
client:
registerWithEureka: false
fetchRegistry: false
server:
waitTimeInMsWhenSyncEmpty: 0
- 启动类EurekaApplication.java，记得用注解EnableEurekaServer开启eureka服务：
package com.bolingcavalry.eureka;
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) throws Exception {
SpringApplication.run(EurekaApplication.class, args);
}
}
- eureka应用已经完成，接下来是服务提供者了
服务提供者provider
- -新建名为provider的应用，pom.xml如下，可见是个普通的web工程，会将自己注册到eureka上去：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>spring-cloud-square-tutorials</artifactId>
<groupId>com.bolingcavalry</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>provider</artifactId>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>com.bolingcavalry</groupId>
<artifactId>client</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-context</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-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<!-- 如果父工程不是springboot，就要用以下方式使用插件，才能生成正常的jar -->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<mainClass>com.bolingcavalry.provider.ProviderApplication</mainClass>
</configuration>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
- 配置文件application.yml：
spring:
application:
name: provider
server:
port: 18080
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
- 启动类ProviderApplication .java：
package com.bolingcavalry.provider;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class ProviderApplication {
public static void main(String[] args) {
SpringApplication.run(ProviderApplication.class, args);
}
}
- web服务类，可见对外提供了两个接口hello-str和hello-obj，前者返回字符串，或者返回对象：
package com.bolingcavalry.provider.controller;
import com.bolingcavalry.client.HelloResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Random;
@RestController
public class Hello {
public static final String HELLO_PREFIX = "Hello World";
@Autowired
DiscoveryClient client;
/**
* 随机取一个provider实例，返回其描述信息，
* 如果只有一个provider实例时，返回的就是当前服务信息
* @return
*/
private String providerDescription() {
List<ServiceInstance> instances = client.getInstances("provider");
ServiceInstance selectedInstance = instances
.get(new Random().nextInt(instances.size()));
return String.format("serviceId [%s], host [%s], port [%d]",
selectedInstance.getServiceId(),
selectedInstance.getHost(),
selectedInstance.getPort());
}
private String dateStr(){
return new SimpleDateFormat("yyyy-MM-dd hh:mm:ss").format(new Date());
}
@GetMapping("/hello-str")
public String helloStr() {
List<ServiceInstance> instances = client.getInstances("provider");
ServiceInstance selectedInstance = instances
.get(new Random().nextInt(instances.size()));
return HELLO_PREFIX
+ " : "
+ providerDescription()
+ ", "
+ dateStr();
}
@GetMapping("/hello-obj")
public HelloResponse helloObj(@RequestParam("name") String name) {
return new HelloResponse(name, dateStr(), providerDescription());
}
}
- 这个provider应用算是个最朴实无华的web服务了
启动服务
- 现在可以将eureka和provider服务先后启动，这样后面的应用编码完成后可以直接测试
consumer-okhttp，基于spring-cloud-square的okhttp能力
-
接下来要创建的应用consumer-okhttp，使用的是spring-cloud-square三种能力的第一种：okhttp
-
pom.xml内容如下，重点是spring-cloud-square-okhttp和spring-cloud-starter-loadbalancer这两个库的引入：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>spring-cloud-square-tutorials</artifactId>
<groupId>com.bolingcavalry</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>consumer-okhttp</artifactId>
<packaging>jar</packaging>
<dependencies>
<dependency>
<groupId>com.bolingcavalry</groupId>
<artifactId>client</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</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-starter-webflux</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-okhttp</artifactId>
<version>0.4.0-SNAPSHOT</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-loadbalancer</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<!-- 如果父工程不是springboot，就要用以下方式使用插件，才能生成正常的jar -->
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<mainClass>com.bolingcavalry.ConsumerApplication</mainClass>
</configuration>
<executions>
<execution>
<goals>
<goal>repackage</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
- 配置文件application.yml，还是常见的那几个配置：应用名、端口、eureka：
spring:
application:
name: consumer-okhttp
server:
port: 18081
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
- 启动类：
package com.bolingcavalry.consumer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class OkhttpApplication {
public static void main(String[] args) {
SpringApplication.run(OkhttpApplication.class, args);
}
}
- 接下来是重要的配置类OkHttpClientConfig.java，用于实例化OkHttpClient.Builder对象并注册到spring环境：
package com.bolingcavalry.consumer;
import okhttp3.OkHttpClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
class OkHttpClientConfig{
@Bean
@LoadBalanced
public OkHttpClient.Builder okHttpClientBuilder() {
return new OkHttpClient.Builder();
}
}
- 然后就可以使用这个Builder来创建OkHttpClient实例了，如下所示，可见入参request的url字段里使用了服务名provider，相当于OkHttpClient内如也能通过服务名取得具体的服务地址，至于是如何获取的，会在后面的文章详细分析，整段代码除了url使用服务名，并没有什么值得关注的地方了，普通的OkHttpClient使用而已：
package com.bolingcavalry.consumer.controller;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import java.io.IOException;
@RestController
public class RemoteHello {
@Autowired
private OkHttpClient.Builder builder;
@GetMapping("/remote-str")
public String hello() throws IOException {
// 直接使用服务名
Request request = new Request.Builder().url("http://provider/hello-str").build();
// 远程访问
Response response = builder.build().newCall(request).execute();
return "get remote response : " + response.body().string();
}
}
- 接下来看看单元测试代码，使用MockMvcRequestBuilders构造http请求，检查返回码和返回内容：
package com.bolingcavalry.consumer.controller;
import com.bolingcavalry.client.Constants;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import static org.hamcrest.Matchers.containsString;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
@SpringBootTest
@AutoConfigureMockMvc
@Slf4j
class RemoteHelloTest {
@Autowired
private MockMvc mvc;
@Test
void hello() throws Exception {
String responseString = mvc.perform(MockMvcRequestBuilders.get("/remote-str").accept(MediaType.APPLICATION_JSON))
.andExpect(status().isOk())
.andExpect(content().string(containsString(Constants.HELLO_PREFIX)))
.andDo(print())
.andReturn()
.getResponse()
.getContentAsString();
log.info("response in junit test :\n" + responseString);
}
}
- 如果eureka和provider都运行起来了，那么此时可以直接运行单元测试类，顺利通过测试，如下图：
consumer-retrofit-okhttp，基于spring-cloud-square的okhttp能力
-
接下来的两个应用都使用了当下热门的retrofit，再搭配Spring Cloud LoadBalance实现服务注册发现，当然了retrofit自身无法完成网络请求处理，要依赖其他库，先看okhttp库的
-
新建应用consumer-retrofit-okhttp，其pom.xml如下，要注意的必须依赖spring-cloud-square-retrofit和spring-cloud-square-okhttp，另外，为了：
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>spring-cloud-square-tutorials</artifactId>
<groupId>com.bolingcavalry</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>consumer-retrofit-okhttp</artifactId>
<dependencies>
<dependency>
<groupId>com.bolingcavalry</groupId>
<artifactId>client</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-retrofit</artifactId>
<version>0.4.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-okhttp</artifactId>
<version>0.4.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<!--skip deploy (this is just a test module) -->
<artifactId>maven-deploy-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
- 配置文件：
spring:
application:
name: consumer-retrofit-okhttp
server:
port: 18082
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
- 启动类：
package com.bolingcavalry.consumer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class RetrofitOkhttpApplication {
public static void main(String[] args) {
SpringApplication.run(RetrofitOkhttpApplication.class, args);
}
}
- 配置类，和前一个应用的没啥区别，想想也是，底层可不都是okhttp么：
package com.bolingcavalry.consumer;
import okhttp3.OkHttpClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.square.retrofit.EnableRetrofitClients;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
@EnableRetrofitClients
class OkHttpClientConfig{
@Bean
@LoadBalanced
public OkHttpClient.Builder okHttpClientBuilder() {
return new OkHttpClient.Builder();
}
}
-
接下来，有趣的部分出现了，先定义HelloService.java，里面的注解RetrofitClient指定了对应的服务名provider，在hello方法生，用GET注解指定了provider提供的web接口，而且hello方法的返回值Call
，和provider服务中hello-obj的返回值HelloResponse也是对应的，还有就是hello的入参对应着provider服务中hello-obj的入参，很熟悉吧，确实，和feign太像了：
package com.bolingcavalry.consumer.service;
import com.bolingcavalry.client.HelloResponse;
import org.springframework.cloud.square.retrofit.core.RetrofitClient;
import retrofit2.Call;
import retrofit2.http.GET;
import retrofit2.http.Query;
@RetrofitClient("provider")
public interface HelloService {
@GET("/hello-obj")
Call<HelloResponse> hello(@Query("name") String name);
}
- 接下来是调用provider服务中hello-obj接口的代码RemoteHello.java，如下所示，神奇的一幕出现了，刚才咱们只写了HelloService接口，并没有写它的实现，但是通过Autowired注解却能 从spring环境拿到实例直接使用，在hello方法中，并没有见到远程调用的代码，而是执行helloService.hello，就能发起远程调用，拿到provider返回的结果：
package com.bolingcavalry.consumer.controller;
import com.bolingcavalry.client.HelloResponse;
import com.bolingcavalry.consumer.service.HelloService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import java.io.IOException;
@RestController
public class RemoteHello {
@Autowired(required = false)
HelloService helloService;
@GetMapping("/remote-obj")
public HelloResponse hello(@RequestParam("name") String name) throws IOException {
return helloService.hello(name).execute().body();
}
}
-
看到这里，聪明的您一定会觉得欣宸就是个没见过世面的乡巴佬：定义HelloService 接口，无需开发实现类，这玩意在mybatis不就有了嘛，居然敢说"神奇"，我觉得您说得对，欣宸确实没见识，大惊小怪的...
-
单元测试类如下，由于返回的是json对象，因此可以用andExpect方法再配合MockMvcResultMatchers，对json进行检查：
package com.bolingcavalry.consumer.controller;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;
import static org.hamcrest.Matchers.is;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
@SpringBootTest
@AutoConfigureMockMvc
@Slf4j
class RemoteHelloTest {
private MockMvc mvc;
@Autowired
private WebApplicationContext webApplicationContext;
@BeforeEach
public void setUp() {
// 在单元测试的时候，MockHttpServletResponse实例的characterEncoding默认是ISO-8859-1，
// 得到的字符串打印出来也是乱码，
// 下面的设置可以解决此问题
if (null==mvc) {
mvc = MockMvcBuilders
.webAppContextSetup(webApplicationContext)
.addFilter((request, response, chain) -> {
response.setCharacterEncoding("UTF-8"); // this is crucial
chain.doFilter(request, response);
}, "/*")
.build();
}
}
@Test
void hello() throws Exception {
// 请求参数是用户名，实时生成一个
String name = System.currentTimeMillis() + "程序员A";
// 请求
String responseString = mvc.perform(
MockMvcRequestBuilders
.get("/remote-obj")
.param("name", name)
.accept(MediaType.APPLICATION_JSON)
)
.andExpect(status().isOk()) // 验证状态
.andExpect(jsonPath("$.name", is(name))) // 验证json中返回的字段是否含有name
.andDo(print())
.andReturn()
.getResponse()
.getContentAsString();
log.info("response in junit test :\n" + responseString);
}
}
- 执行单元测试，如下图，顺利通过：
consumer-retrofit-webflux，基于spring-cloud-square的retrofit + webflux
- 最后登场的是consumer-retrofit-webflux，pom.xml如下，依赖库是spring-cloud-square-retrofit + spring-boot-starter-webflux的组合：
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<parent>
<artifactId>spring-cloud-square-tutorials</artifactId>
<groupId>com.bolingcavalry</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<artifactId>consumer-retrofit-webflux</artifactId>
<dependencies>
<dependency>
<groupId>com.bolingcavalry</groupId>
<artifactId>client</artifactId>
<version>${project.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-retrofit</artifactId>
<version>0.4.0-SNAPSHOT</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-square-retrofit-webclient</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-webflux</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<!--skip deploy (this is just a test module) -->
<artifactId>maven-deploy-plugin</artifactId>
<configuration>
<skip>true</skip>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
- 配置文件application.yml:
spring:
application:
name: consumer-retrofit-webflux
server:
port: 18083
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
- 启动类RetrofitWebfluxApplication.java
package com.bolingcavalry.consumer;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class RetrofitWebfluxApplication {
public static void main(String[] args) {
SpringApplication.run(RetrofitWebfluxApplication.class, args);
}
}
- 配置类AppConfiguration.java，使用的注解是EnableRetrofitClients，实例化的Buider对象是WebClient.Builder，和前面的不一样，要格外注意：
package com.bolingcavalry.consumer;
import okhttp3.OkHttpClient;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.cloud.square.retrofit.webclient.EnableRetrofitClients;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.reactive.function.client.WebClient;
@Configuration
@EnableRetrofitClients
class AppConfiguration {
@Bean
@LoadBalanced
public WebClient.Builder builder() {
return WebClient.builder();
}
}
-
接下来是接口定义，注意hello方法的返回值是Mono
，这是weflux风格的返回值，代表异步的0个或一个元素：
package com.bolingcavalry.consumer.service;
import com.bolingcavalry.client.HelloResponse;
import org.springframework.cloud.square.retrofit.core.RetrofitClient;
import reactor.core.publisher.Mono;
import retrofit2.http.GET;
import retrofit2.http.Query;
@RetrofitClient("provider")
public interface HelloService {
@GET("/hello-obj")
Mono<HelloResponse> hello(@Query("name") String name);
}
- 最后是单元测试类，和前面的没啥区别：
package com.bolingcavalry.consumer.controller;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.http.MediaType;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;
import static org.hamcrest.Matchers.is;
import static org.springframework.test.web.servlet.result.MockMvcResultHandlers.print;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
@SpringBootTest
@AutoConfigureMockMvc
@Slf4j
class RemoteHelloTest {
private MockMvc mvc;
@Autowired
private WebApplicationContext webApplicationContext;
@BeforeEach
public void setUp() {
// 在单元测试的时候，MockHttpServletResponse实例的characterEncoding默认是ISO-8859-1，
// 得到的字符串打印出来也是乱码，
// 下面的设置可以解决此问题
if (null==mvc) {
mvc = MockMvcBuilders
.webAppContextSetup(webApplicationContext)
.addFilter((request, response, chain) -> {
response.setCharacterEncoding("UTF-8"); // this is crucial
chain.doFilter(request, response);
}, "/*")
.build();
}
}
@Test
void hello() throws Exception {
// 请求参数是用户名，实时生成一个
String name = System.currentTimeMillis() + "程序员B";
// 请求
String responseString = mvc.perform(
MockMvcRequestBuilders
.get("/remote-obj")
.param("name", name)
.accept(MediaType.APPLICATION_JSON)
)
.andExpect(status().isOk()) // 验证状态
.andExpect(jsonPath("$.name", is(name))) // 验证json中返回的字段是否含有name
.andDo(print())
.andReturn()
.getResponse()
.getContentAsString();
log.info("response in junit test :\n" + responseString);
}
}
- 运行单元测试，如下图，顺利通过，并且红框中所示的中文也没有乱码：
- 至此，spring-cloud-square的三种类型，咱们全部编码体验了一遍，聪明的您当然不会只满足于使用它们，接下来文章，咱们就去深入spring-cloud-square源码，研究其实现的细节，欣宸原创，必不会辜负您的期待！
原文：https://www.cnblogs.com/bolingcavalry/p/15491935.html
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