服务消费者（Feign-下）

上一篇文章中已经讲述 Feign的基本用法，本章主要概述 FeignClient GET/POST/PUT/DELETE restful写法以及 Feign 拦截器，与配置优化方案，关闭HttpClient开启OKHTTP…

- 准备工作

1.启动Consul，所有文章都将以Consul作为服务注册中心

2.创建 battcn-feign-hello，battcn-feign-hi（本文代码基于上篇改造）

3.服务（Hi）-> FeignClient -> 服务（Hello），通过实现 RequestInterceptor 传递 header 信息

- battcn-feign-hello

- pom.xml

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<dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-consul-discovery</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies>

- BattcnFeignHelloApplication.java

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@SpringBootApplication @EnableDiscoveryClient public class BattcnFeignHelloApplication { public static void main(String[] args) { SpringApplication.run(BattcnFeignHelloApplication.class, args); } }

- Student.java

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public class Student { private Long id; private String name; private String email; //...get set @Override public String toString() { return "Student{" + "id=" + id + ", name='" + name + '\'' + ", email='" + email + '\'' + '}'; } public Student(){} public Student(Long id, String name, String email) { this.id = id; this.name = name; this.email = email; } }

- HelloController.java

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@RestController @RequestMapping("/hello") public class HelloController { @Autowired HttpServletRequest request; static Logger LOGGER = LoggerFactory.getLogger(HelloController.class); @ResponseStatus(HttpStatus.OK) @GetMapping public Student findStudentByName(@RequestParam("name") String name,@RequestHeader(name = "token",required = false)) { // TODO：不做具体代码实现，只打印Log LOGGER.info("[查询参数] - [{}]", name); LOGGER.info("[Token] - [{}]",token); LOGGER.info("[Auth] - [{}]",request.getHeader("Auth")); return new Student(1L,"挽歌-GET","1837307557@qq.com"); } @ResponseStatus(HttpStatus.CREATED) @PostMapping public Student addStudent(@RequestBody Student student) { // TODO：不做具体代码实现，只打印Log LOGGER.info("[添加信息] - [{}]", student.toString()); return new Student(2L,"挽歌-SAVA","1837307557@qq.com"); } @ResponseStatus(HttpStatus.CREATED) @PutMapping("/{studentId}") public Student editStudent(@RequestBody Student student, @PathVariable("studentId") Long studentId) { // TODO：不做具体代码实现，只打印Log LOGGER.info("[修改信息] - [{}]", student.toString()); return new Student(3L,"挽歌-EDIT","1837307557@qq.com"); } @ResponseStatus(HttpStatus.NO_CONTENT) @DeleteMapping("/{studentId}") public void deleteStudent(@PathVariable("studentId") Long studentId) { // TODO：不做具体代码实现，只打印Log LOGGER.info("[根据编号删除学生] - [{}]", studentId); } }

- bootstrap.yml

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server: port: 8765 spring: application: name: battcn-feign-hello cloud: consul: host: localhost port: 8500 enabled: true discovery: enabled: true prefer-ip-address: true

- 测试

访问：http://localhost:8765/hello?name=Levin

显示：{"id":1,"name":"挽歌-GET","email":"1837307557@qq.com"} 代表我们服务启动成功

- battcn-feign-hi

- pom.xml

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<dependencies> <dependency> <groupId>io.github.openfeign</groupId> <artifactId>feign-okhttp</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-feign</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-consul-discovery</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> <dependency> <groupId>com.battcn</groupId> <artifactId>battcn-starter-swagger</artifactId> <version>1.0.1</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies>

- BattcnFeignHiApplication.java

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@EnableDiscoveryClient @EnableFeignClients @SpringBootApplication public class BattcnFeignHiApplication { public static void main(String[] args) { SpringApplication.run(BattcnFeignHiApplication.class, args); } }

- HiController.java

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@RestController @RequestMapping("/hi") public class HiController { static Logger LOGGER = LoggerFactory.getLogger(HiController.class); @Autowired HelloClient helloClient; @ResponseStatus(HttpStatus.OK) @GetMapping public Student find(@RequestParam("name") String name,@RequestHeader(name="token",required = false)String token) { // TODO：只是演示Feign调用的方法 LOGGER.info("[Token] - [{}]",token); return helloClient.findStudentByName(name,token); } @ResponseStatus(HttpStatus.CREATED) @PostMapping public Student add(@RequestBody Student student) { // TODO：只是演示Feign调用的方法 return helloClient.addStudent(student); } @ResponseStatus(HttpStatus.CREATED) @PutMapping("/{studentId}") public Student edit(@RequestBody Student student, @PathVariable("studentId") Long studentId) { // TODO：只是演示Feign调用的方法 return helloClient.editStudent(student, studentId); } @ResponseStatus(HttpStatus.NO_CONTENT) @DeleteMapping("/{studentId}") public void delete(@PathVariable("studentId") Long studentId) { // TODO：只是演示Feign调用的方法 helloClient.deleteStudent(studentId); } }

- MyFeignInterceptor.java

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/** * 传递Token * @author Levin * @date 2017-07-29. */ @Configuration public class MyFeignInterceptor implements RequestInterceptor { @Override public void apply(RequestTemplate requestTemplate) { requestTemplate.header("Auth","My Name's request header Auth"); } }

- HelloClient.java

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package com.battcn.client; import com.battcn.pojo.Student; import org.springframework.cloud.netflix.feign.FeignClient; import org.springframework.http.HttpStatus; import org.springframework.web.bind.annotation.*; /** * 模拟完整的CRUD操作 */ @FeignClient(name = "battcn-feign-hello") public interface HelloClient { @ResponseStatus(HttpStatus.OK) @GetMapping("/hello") Student findStudentByName(@RequestParam("name") String name,@RequestHeader(name="token",required = false)String token); @ResponseStatus(HttpStatus.CREATED) @PostMapping("/hello") Student addStudent(@RequestBody Student student); @ResponseStatus(HttpStatus.CREATED) @PutMapping("/hello/{studentId}") Student editStudent(@RequestBody Student student, @PathVariable("studentId") Long studentId); @ResponseStatus(HttpStatus.NO_CONTENT) @DeleteMapping("/hello/{studentId}") void deleteStudent(@PathVariable("studentId") Long studentId); }

- bootstrap.yml

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server: port: 8766 spring: application: name: battcn-feign-hi cloud: consul: host: localhost port: 8500 enabled: true discovery: enabled: true prefer-ip-address: true #Hystrix支持，如果为true，hystrix库必须在classpath中 feign: okhttp: enabled: true #开启OKHTTP支持，依赖 （feign-okhttp）默认HttpClient #请求和响应GZIP压缩支持 compression: request: enabled: true #支持压缩的mime types mime-types: text/xml,application/xml,application/json min-request-size: 2048 response: enabled: true hystrix: enabled=false # 日志支持 logging: level: project.com.battcn.UserClient: DEBUG #以下就是需要写的配置，注意base-package就可以了 swagger: enable: true #是否开启Swagger api-info: description: ${spring.application.name} license: ${spring.application.name} license-url: http://blog.battcn.com terms-of-service-url: http://blog.battcn.com title: 鏖战八方 version: "@project.version@" contact: email: 1837307557@qq.com name: 挽歌 url: http://blog.battcn.com docket: base-package: com.battcn.controller #扫描路径，建议以Controller的父包为主 group-name: ${spring.application.name}

- 测试

访问：http://localhost:8766/swagger-ui.html

使用Swagger做测试

swagger测试

此处只演示GET，PUT，DELETE，POST 示例代码都包括，自行测试即可

日志：

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2017-07-29 18:21:26.854 INFO 12620 --- [nio-8765-exec-2] com.battcn.controller.HelloController : [查询参数] - [Levin] 2017-07-29 18:21:26.854 INFO 12620 --- [nio-8765-exec-2] com.battcn.controller.HelloController : [Token] - [Token HA] 2017-07-29 18:21:26.854 INFO 12620 --- [nio-8765-exec-2] com.battcn.controller.HelloController : [Auth] - [My Name's request header Auth]

如果未实现 RequestInterceptor 那么 LOGGER.info("[Auth] - [{}]",request.getHeader("Auth")); 就无法获取到 request 中的信息

- 流程图

画图工具：https://www.processon.com/

流程图