# springcloud-demo

**Repository Path**: tree3170/springcloud-demo

## Basic Information

- **Project Name**: springcloud-demo
- **Description**: springclouddemo示例：eureka、feign、ribbton、zuul、config、hystrix等
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2019-07-06
- **Last Updated**: 2021-03-07

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# spring-cloud-demo

## 1. 启动高可用eureka集群：eureka-server

* 添加jar包

```xml
<dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Finchley.RELEASE</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

 <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>

```
* @EnableEurekaServer
* 配置
```yaml
# 设置端口
server:
  port: 1111
# 设置hostname
eureka:
  server:
    enable-self-preservation: false #关闭自我保护
    #eviction-interval-timer-in-ms: 1000 #续期时间，即扫描失效服务的间隔时间
  instance:
    hostname: localhost
    non-secure-port: ${server.port}
    prefer-ip-address: true
  client:
    # 由于注册中心是用于维护服务实例，它并不需要检索服务，所以设置为false
    fetch-registry: false
    # 由于该应用是eureka-server，是注册中心，故不需要注册自己到注册中心
    register-with-eureka: false
    # service url指向其他eureka节点，如peer2
    service-url:
      defaultZone: http://peer1:1111/eureka/

```
* 访问： 

## 2 启动高可用服务：user-service
* pom
```xml
<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
```
* 注解并注入resttemlate
EnableDiscoveryClient
```java
@Bean
@LoadBalanced
Resttemplate restTemplate(){
 return new Resttemplate();
}
```
* 配置
```yaml
eureka:
  client:
    service-url:
#      defaultZone: http://peer1:1111/eureka/,http://peer2:1112/eureka/
      defaultZone: http://localhost:1111/eureka/
```


* 运行
 java -jar user-service-0.0.1-SNAPSHOT.jar --server.port=8081
 java -jar user-service-0.0.1-SNAPSHOT.jar --server.port=8082

* 访问eureka server

* 访问controller

## 3 启动consumer： ribbon-consumer
* pom依赖
```xml
<dependency>
			<groupId>org.springframework.cloud</groupId>
			<artifactId>spring-cloud-starter-openfeign</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>com.google.guava</groupId>
                    <artifactId>guava</artifactId>
                </exclusion>
            </exclusions>
		</dependency>

```
* 启动discovery：@EnableDiscoveryClient
* 启动feign：@EnableFeignClients
* 使用方式一：resttemplate
** 1. ribbon, 利用restTemplate
```
http://localhost:9000/ribbon/hello-ribbon
```
多次请求，查看是否user-service是否落在台服务器（ribbon默认采用轮询）

* 方式二：feign
** 添加FeignClient的service interface
@FeignClient

* 2. 实现Feign并带有hystrix的熔断（测试熔断可以关闭服务方User-Service）
```
http://localhost:9000/ribbon/hello-feign
```
注意：
```
#fall back需要开启hystrix
feign:
  hystrix:
    enabled: true
```
* 访问

* 获取ribbon的server ：http://192.168.1.101:9000/ribbon/servers
```json
[
  {
    "instanceInfo": {
      "hostName": "192.168.1.101",
      "overriddenStatus": "UNKNOWN",
      "lastUpdatedTimestamp": 1615091596156,
      "metadata": {
        "management.port": "8081"
      },
      "healthCheckUrl": "http://192.168.1.101:8081/actuator/health",
      "statusPageUrl": "http://192.168.1.101:8081/actuator/info",
      "appName": "USER-SERVICE",
      "vipAddress": "user-service",
      "secureVipAddress": "user-service",
      "leaseInfo": {
        "renewalIntervalInSecs": 30,
        "evictionTimestamp": 0,
        "durationInSecs": 90,
        "serviceUpTimestamp": 1615091596156,
        "registrationTimestamp": 1615091596156
      },
      "lastDirtyTimestamp": 1615091596100,
      "homePageUrl": "http://192.168.1.101:8081/",
      "version": "unknown",
      "ipAddr": "192.168.1.101",
      "countryId": 1,
      "sid": "na",
      "securePort": 443,
      "actionType": "ADDED",
      "instanceId": "192.168.1.101:user-service:8081",
      "dataCenterInfo": {
        "name": "MyOwn"
      },
      "port": 8081,
      "isCoordinatingDiscoveryServer": false,
      "status": "UP"
    },
    "port": 8081,
    "zone": "defaultZone",
    "host": "192.168.1.101",
    "id": "192.168.1.101:8081",
    "readyToServe": true
  }
]
```

## 4 启动zuul网关：
http://localhost:3001/baidu
1. 读取spring cloud zuul包中的spring.factories文件， 加载ZuulServerAutoConfiguration，ZuulProxyAutoConfiguration
2.  初始化zuulHandlerMapping、RouteLocator、zuulController
前面提到，所以路由请求都会被控制器ZuulControoler拦截到，最终交由ZuulServlet来处理，核心处理代码如下：
3.ZuulServlet实现pre、route、post
参考：
[spring-cloud-zuul原理解析](https://segmentfault.com/a/1190000015915402)
4. 源码解析参考：有道云笔记--》springcloud--》《Zuul源码分析》


## 5. Feign
a. 添加依赖
```
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
    <exclusions>
       <exclusion>
           <groupId>com.google.guava</groupId>
           <artifactId>guava</artifactId>
       </exclusion>
    </exclusions>
</dependency>

```

b. 允许Feign
```
@EnableFeignClients
#fall back需要开启hystrix
feign:
  hystrix:
    enabled: true
```

c. 使用方法参考类： 
```
UserFeignService
UserFeignServiceFallbackFactory
打开客户端Feign调用日志, 同时日志要开启
    <logger name="logging.level.com.tree.userservice.sao.UserFeignService" level="DEBUG" />
FullLogConfiguration
```