最容易学会的springboot gralde spring cloud 多模块微服务项目

Sping Cloud

服务发现组件 Eureka

Eureka Server 服务中心

Eureka Client 启动 就会注册到Server

1. 用到的库
   spring-cloud-starter-netflix-eureka-server
   spring-cloud-starter-netflix-eureka-client
2. 注解
   @EnableEurekaServer
   @EnableEurekaClient
3. application.yml 配置信息

//服务端
server:
  port: 6868
eureka:
  client:
    service-url:
      defaultZone: http://127.0.0.1:${server.port}/eureka/
    register-with-eureka: false
    fetch-registry: false
spring:
  application:
    name: study-eureka
    //客户端

server:
  port: 8087
eureka:
  client:
    service-url:
      defaultZone: http://127.0.0.1:6868/eureka/
  instance:
    prefer-ip-address: true
spring:
  application:
    name: study-admin

4. 打开网页可以看到http://localhost:6868/

Feign实现服务间的调用（默认带有负载均衡）

Feign是简化Java HTTP客户端开发的工具（java-to-httpclient-binder），它的灵感

来自于Retrofit、JAXRS-2.0和WebSocket。Feign的初衷是降低统一绑定Denominator到

HTTP API的复杂度，不区分是否为restful

1. 库
   spring-cloud-starter-openfeign
2. 注解

@EnableFeignClients
@EnableDiscoveryClient
创建FeignClient接口

@FeignClient(value = "study-api", fallback = ApiClientImpl.class)
@Component
public interface ApiClient {
    //, @RequestHeader(value = "token", required = false) String token
    @PostMapping(value = "/api/test")
    R<String> test(@RequestParam(value = "data") String data);
}

熔断器Hystrix

1. 配置

 feign:
  hystrix:
    enabled: true

2. 代码

   @Component
public class ApiClientImpl implements ApiClient {

    @Override
    public R<String> test(String data) {
        return RUtil.success("熔断器起作用了" + data);
    }
}

微服务网关Zuul

微服务网关是介于客户端和服务器端之间的中间层，所有的外部请求都会先经过微服务网关,然后通过spring

-application-name 转发对应的服务

1. 库

spring-cloud-starter-netflix-zuul

2. 注解
   @EnableZuulProxy
3. 路由转发

zuul:
  routes:
    study-api:
      path: /api/**
      serviceId: study-api
    study-admin:
      path: /admin/**
      serviceId: study-admin

4. 过滤器

package com.ityu.studyadminzuul.filter;

import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.apache.commons.lang3.StringUtils;
import org.springframework.stereotype.Component;

import javax.servlet.http.HttpServletRequest;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;

@Component
public class WebFilter extends ZuulFilter {
    @Override
    public String filterType() {
        return "pre";
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        return true;
    }

    @Override
    public Object run() throws ZuulException {
        System.out.println("拦截器启动了");
        RequestContext currentContext = RequestContext.getCurrentContext();
        HttpServletRequest request = currentContext.getRequest();
        if (request.getMethod().equals("OPTIONS")) {
            return null;
        }
        String url = request.getRequestURL().toString();
        if (url.indexOf("/admin/login") > 0) {
            return null;
        }

        String header = request.getHeader("token");
        if (StringUtils.isNotEmpty(header)) {
            currentContext.addZuulRequestHeader("token", header);
        } else {
            try {
                //URLDecoder.decode("xxxxx","UTF-8"); 解码 微服务获取时解码
                //在网关添加内容是编码
                currentContext.addZuulRequestHeader("token", URLEncoder.encode("没有头的信息", "UTF-8"));
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}

集中配置组件SpringCloudConfig

config server

config client

1. 库

 spring-cloud-config-server
spring-cloud-starter-config

2. 注解
   @EnableConfigServer
   3.配置信息

 cloud:
    config:
      server:
        git:
          uri: https://gitee.com/lanlingkeji_yu.jl/srpingcloudstudyconfig.git

4.客户端配置信息 bootstrap.yml

spring:
  cloud:
    config:
      name: api
      profile: dev
      lable: master
      uri: http://127.0.0.1:12000

消息总线组件SpringCloudBus

SpringCloudBus来实现配置的自动更新

1. 库
   spring-cloud-stream-binder-rabbit
   spring-cloud-bus
   spring-boot-starter-actuator
2. 注解
   @RefreshScope 刷新自定义配置信息
3. 配置

management:
  endpoints:
    web:
      exposure:
        include: bus-refresh

4. 客戶端也要配置 rabbitmq 信息