Spring Cloud Netflix 创建服务消费者——Feign（五）
概述
Feign 是一个声明式的伪 Http 客户端，它使得写 Http 客户端变得更简单。使用 Feign，只需要创建一个接口并注解。它具有可插拔的注解特性，可使用 Feign 注解和 JAX-RS 注解。Feign 支持可插拔的编码器和解码器。Feign 默认集成了 Ribbon，并和 Eureka 结合，默认实现了负载均衡的效果
Feign 采用的是基于接口的注解
Feign 整合了 ribbon
创建服务消费者
完整pom文件
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
| <?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>2.2.2.RELEASE</version>
<relativePath/>
</parent>
<groupId>com.xzt</groupId>
<artifactId>cloud-feign-service</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>cloud-feign-service</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Hoxton.RELEASE</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<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>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
|
application.yml
1
2
3
4
5
6
7
8
9
10
11
| spring:
application:
name: cloud-feign-service
server:
port: 8765
eureka:
client:
serviceUrl:
defaultZone: http://localhost:8761/eureka/
|
启动类
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
| package com.xzt.feign;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication
@EnableFeignClients
@EnableEurekaClient
public class CloudFeignServiceApplication {
public static void main(String[] args) {
SpringApplication.run(CloudFeignServiceApplication.class, args);
}
}
|
Service
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
| package com.xzt.feign.test.service;
import com.xzt.feign.test.beans.User;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
@FeignClient(value = "cloud-admin-service")
public interface AdminService {
@RequestMapping(value = "hi", method = RequestMethod.GET)
String sayHi(@RequestParam(value = "message") String message);
@RequestMapping(value = "req_post", method = RequestMethod.POST)
User postHi(@RequestBody User user);
}
|
Controller
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
| package com.xzt.feign.test.controller;
import com.xzt.feign.test.beans.User;
import com.xzt.feign.test.service.AdminService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class AdminController {
@Autowired
private AdminService adminService;
@RequestMapping(value = "hi", method = RequestMethod.GET)
public String sayHi(@RequestParam String message) {
return adminService.sayHi(message);
}
@RequestMapping(value = "req_post", method = RequestMethod.GET)
public String postHi(String userName, String password) {
User user = new User();
user.setUserName(userName);
user.setPassword(password);
User res = adminService.postHi(user);
return String.format("%s ,welcome! I am from port %s", userName, res.getPort());
}
}
|
测试
GET
访问http://localhost:8765/hi?message=12345,将出现以下内容
1
| Hi，your message is : 12345 i am from port : 8762
|
POST
访问http://localhost:8765/req_post?userName=mo&password=123456,将出现以下内容
1
| mo ,welcome! I am from port 8762
|
如果配置多个cloud-admin-service服务，多次访问此接口，端口号应当随之变化
