前言

本节内容我们主要介绍一下web访问的另一种形式，通过函数式web实现一个restful风格的http请求案例。函数式web是spring5.2之后的一个新特性，可以通过函数去定义web请求的处理流程，使得代码更为简洁，耦合性也降低了。

正文

函数式web的四大核心对象

- RouterFunction：定义路由信息

- RequestPredicates：定义请求规则，包括请求参数、请求方式等

- ServerRequest：封装请求参数

- ServerResponse：封装响应参数

定义一个函数式web的路由组件WebFunctionConfig配置类

- 实现代码

package com.yundi.isbc.config;import com.yundi.isbc.handler.PersonHandlerService;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.MediaType;
import org.springframework.web.servlet.function.RequestPredicates;
import org.springframework.web.servlet.function.RouterFunction;
import org.springframework.web.servlet.function.RouterFunctions;
import org.springframework.web.servlet.function.ServerResponse;@Configuration
public class WebFunctionConfig {/*** 用户信息管理** @param personHandlerService* @return*/@Beanpublic RouterFunction<ServerResponse> personRouter(PersonHandlerService personHandlerService) {RouterFunction<ServerResponse> personRouterFunction = RouterFunctions.route().GET("/person/{id}", RequestPredicates.accept(MediaType.ALL), personHandlerService::getPerson).GET("/persons", personHandlerService::getPersons).POST("/person", RequestPredicates.accept(MediaType.APPLICATION_JSON), personHandlerService::savePerson).PUT("/person", RequestPredicates.accept(MediaType.APPLICATION_JSON), personHandlerService::updatePerson).DELETE("/person/{id}", personHandlerService::deletePerson).build();return personRouterFunction;}}

- 在该类中实现了restful风格的请求完成用户管理功能的开发

用户person对象的实体类

- 用户Person类

package com.yundi.isbc.entity;import com.fasterxml.jackson.dataformat.xml.annotation.JacksonXmlRootElement;
import lombok.Data;
import lombok.experimental.Accessors;import java.util.ArrayList;
import java.util.List;@Accessors(chain = true)
@Data
public class Person {/*** id*/private String id;/*** 名称*/private String name;/*** 年龄*/private Integer age;/*** 手机号*/private String phone;/*** 住址*/private List<Address> addresses = new ArrayList<>();
}

- 用户地址类

package com.yundi.isbc.entity;import lombok.Data;
import lombok.experimental.Accessors;@Accessors(chain = true)
@Data
public class Address {/*** 地址名称*/private String addressName;
}

定义业务实现接口PersonHandlerService

- 实现代码

package com.yundi.isbc.handler;import jakarta.servlet.ServletException;
import org.springframework.web.servlet.function.ServerRequest;
import org.springframework.web.servlet.function.ServerResponse;import java.io.IOException;public interface PersonHandlerService {/*** 根据id获取用户信息** @param serverRequest* @return*/ServerResponse getPerson(ServerRequest serverRequest);/*** 获取全部用户* @param serverRequest* @return*/ServerResponse getPersons(ServerRequest serverRequest);/*** 保存用户* @param serverRequest* @return*/ServerResponse savePerson(ServerRequest serverRequest) throws ServletException, IOException;/*** 更新用户信息* @param serverRequest* @return*/ServerResponse updatePerson(ServerRequest serverRequest) throws ServletException, IOException;/*** 删除用户* @param serverRequest* @return*/ServerResponse deletePerson(ServerRequest serverRequest);
}

- 定义各功能业务实现接口方法

定义业务实现类PersonHandlerServiceImpl

- 实现代码

package com.yundi.isbc.handler.impl;import com.yundi.isbc.entity.Address;
import com.yundi.isbc.entity.Person;
import com.yundi.isbc.handler.PersonHandlerService;
import jakarta.servlet.ServletException;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
import org.springframework.web.servlet.function.ServerRequest;
import org.springframework.web.servlet.function.ServerResponse;import java.io.IOException;
import java.util.Arrays;@Slf4j
@Service
public class PersonHandlerServiceImpl implements PersonHandlerService {@Overridepublic ServerResponse getPerson(ServerRequest serverRequest) {log.info("==================获取用户信息==================");String id = serverRequest.pathVariable("id");log.info("用户id:{}", id);return ServerResponse.ok().body(new Person().setId("1").setName("xiaoming").setAge(18).setPhone("18288474612").setAddresses(Arrays.asList(new Address().setAddressName("北京市朝阳区"))));}@Overridepublic ServerResponse getPersons(ServerRequest serverRequest) {log.info("==================获取全部用户信息==================");return ServerResponse.ok().body(Arrays.asList(new Person().setId("1").setName("xiaoming").setAge(18).setPhone("18288474612").setAddresses(Arrays.asList(new Address().setAddressName("北京市朝阳区")))));}@Overridepublic ServerResponse savePerson(ServerRequest serverRequest) throws ServletException, IOException {log.info("==================保存用户信息==================");Person person = serverRequest.body(Person.class);log.info("用户信息：{}", person);return ServerResponse.ok().build();}@Overridepublic ServerResponse updatePerson(ServerRequest serverRequest) throws ServletException, IOException {log.info("==================更新用户信息==================");Person person = serverRequest.body(Person.class);log.info("用户信息：{}", person);return ServerResponse.ok().build();}@Overridepublic ServerResponse deletePerson(ServerRequest serverRequest) {log.info("==================删除用户信息==================");String id = serverRequest.pathVariable("id");log.info("用户id:{}", id);return ServerResponse.ok().build();}
}

- 具体业务实现