Spring Cloud 2天速学学习记录
基础知识补充
对象复制
Product product = productService.findById(id);
Product result = new Product();
BeanUtils.copyProperties(product,result);
线程睡眠
TimeUnit.SECONDS.sleep(1);
Spring Boot使用Redis
- 依赖
org.springframework.boot
spring-boot-starter-data-redis
- 配置文件（Spring下）
redis:
database: 0
host: 127.0.0.1
port: 6379
timeout: 2000
- 日志打印
private final Logger logger = LoggerFactory.getLogger(getClass);
logger.info("test");
项目使用参见熔断一章
创建Eureka时idea勾选依赖。
创建消费者时idea勾选依赖。
消费者Ribbon
创建Ribbon时idea勾选依赖。
- web > web
- clouding discovery > eureka discovery
- clouding routing > ribbon
启动类加入
@Bean
@LoadBalanced
public RestTemplate restTemplate() {
return new RestTemplate();
}
调用方法一(Map可以接受Json数据)
Map<String,Object> productMap = restTemplate.getForObject("http://product-service/api/v1/product/find?id="+productId, Map.class);
调用方法二
@Autowired
private LoadBalancerClient loadBalancer;
ServiceInstance instance = loadBalancer.choose("product-service");
String url = String.format("http://%s:%s/api/v1/product/find?id="+productId, instance.getHost(),instance.getPort());
RestTemplate restTemplate = new RestTemplate();
Map<String,Object> productMap = restTemplate.getForObject(url, Map.class);
自定义负载均衡
product-service:
ribbon:
NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule
消费者feign
依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
启动类添加
@EnableFeignClients
增加一个接口
@FeignClient(name = "product-service")
public interface ProductClient {
@GetMapping("/api/v1/product/find")
String findById(@RequestParam(value = "id") int id);
}
调用
@Autowired
private ProductClient productClient;
String response = productClient.findById(productId);
修改超时调用
feign:
client:
config:
default:
connectTimeout: 2000
readTimeout: 2000
feign包含ribben。自定义负载均衡同上
Hystrix熔断
使用方法一
-
加入依赖
org.springframework.cloud spring-cloud-starter-netflix-hystrix -
启动类加入注解
@EnableCircuitBreaker
- 方法里加入注解
@RequestMapping("save")
@HystrixCommand(fallbackMethod = "saveOrderFail")
public Object save(@RequestParam("user_id")int userId, @RequestParam("product_id") int productId){
Map<String, Object> data = new HashMap<>();
data.put("code", 0);
data.put("data", productOrderService.save(userId, productId));
return data;
}
//注意，方法签名一定要要和api方法一致
private Object saveOrderFail(int userId, int productId){
Map<String, Object> msg = new HashMap<>();
msg.put("code", -1);
msg.put("msg", "抢购人数太多，您被挤出来了，稍等重试");
return msg;
}
方法二 Feign开启hystrix
- 配置文件
feign:
hystrix:
enabled: true
- Client上加这个方法，自定义一个返回类
@FeignClient(name = "product-service", fallback = ProductClientFallback.class)
- 代码例子
/**
* 针对商品服务，错降级处理
*/
@Component
public class ProductClientFallback implements ProductClient {
@Override
public String findById(int id) {
System.out.println("feign 调用product-service findbyid 异常");
return null;
}
}
熔断降级项目报警
- 使用Redis注解
@Autowired
private StringRedisTemplate redisTemplate;
/**
拿取key-value类型值
**/
String sendValue = redisTemplate.opsForValue().get(saveOrderKye);
- 代码示例
//监控报警
String saveOrderKye = "save-order";
String sendValue = redisTemplate.opsForValue().get(saveOrderKye);
final String ip = request.getRemoteAddr();
new Thread( ()->{
if (StringUtils.isBlank(sendValue)) {
System.out.println("紧急短信，用户下单失败，请离开查找原因,ip地址是="+ip);
//发送一个http请求，调用短信服务 TODO
redisTemplate.opsForValue().set(saveOrderKye, "save-order-fail", 20, TimeUnit.SECONDS);
}else{
System.out.println("已经发送过短信，20秒内不重复发送");
}
}).start();
Map<String, Object> msg = new HashMap<>();
msg.put("code", -1);
msg.put("msg", "抢购人数太多，您被挤出来了，稍等重试");
return msg;
熔断超时时间处理
hystrix:
command:
default:
execution:
isolation:
thread:
timeoutInMilliseconds: 4000
断路器Dashboard监控仪表盘实战
- 加入依赖
org.springframework.cloud
spring-cloud-starter-netflix-hystrix-dashboard
org.springframework.boot
spring-boot-starter-actuator
- 启动类增加注解
@EnableHystrixDashboard
- 配置文件增加endpoint
management:
endpoints:
web:
exposure:
include: "*"
-
4、访问入口
http://localhost:8781/hystrixHystrix Dashboard输入： http://localhost:8781/actuator/hystrix.stream
微服务网关zuul
- 创建勾选依赖
Cloud Discovery 》 Eureka Discovery
Cloud Routing 》 Zuul - 启动类加入注解
@EnableZuulProxy
默认访问规则
http://gateway:port/service-id/**
例子：默认 /order-service/api/v1/order/save?user_id=2&product_id=1
自定义 /xdclass_order/api/v1/order/save?user_id=2&product_id=1
自定义路由转发：
zuul:
routes:
order-service: /apigateway/**
环境隔离配置：
需求 ：不想让默认的服务对外暴露接口
/order-service/api/v1/order/save
配置：
zuul:
ignored-patterns:
- /*-service/api/v1/order/save
Zuul常用问题分析
1、路由名称定义问题
路由映射重复覆盖问题
2、Http请求头过滤问题
3、过滤器执行顺序问题 ，过滤器的order值越小，越先执行
4、共享RequestContext，上下文对象
自定义Zuul过滤器实现登录鉴权实战
简介：自定义Zuul过滤器实现登录鉴权实战
1、新建一个filter包
2、新建一个类，实现ZuulFilter，重写里面的方法
3、在类顶部加注解，@Component,让Spring扫描
package net.xdclass.apigateway.filter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.apache.commons.lang.StringUtils;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import javax.servlet.http.HttpServletRequest;
import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;
/**
* 登录过滤器
*/
@Component
public class LoginFilter extends ZuulFilter {
/**
* 过滤器类型，前置过滤器
* @return
*/
@Override
public String filterType() {
return PRE_TYPE;
}
/**
* 过滤器顺序，越小越先执行
* @return
*/
@Override
public int filterOrder() {
return 4;
}
/**
* 过滤器是否生效
* @return
*/
@Override
public boolean shouldFilter() {
RequestContext requestContext = RequestContext.getCurrentContext();
HttpServletRequest request = requestContext.getRequest();
//System.out.println(request.getRequestURI()); ///apigateway/product/api/v1/product/list
//System.out.println(request.getRequestURL()); //http://localhost:9000/apigateway/product/api/v1/product/list
//ACL
if ("/apigateway/order/api/v1/order/save".equalsIgnoreCase(request.getRequestURI())){
return true;
}else if ("/apigateway/order/api/v1/order/list".equalsIgnoreCase(request.getRequestURI())){
return true;
}else if ("/apigateway/order/api/v1/order/find".equalsIgnoreCase(request.getRequestURI())){
return true;
}
return false;
}
/**
* 业务逻辑
* @return
* @throws ZuulException
*/
@Override
public Object run() throws ZuulException {
//JWT
RequestContext requestContext = RequestContext.getCurrentContext();
HttpServletRequest request = requestContext.getRequest();
//token对象
String token = request.getHeader("token");
if(StringUtils.isBlank((token))){
token = request.getParameter("token");
}
//登录校验逻辑 根据公司情况自定义 JWT
if (StringUtils.isBlank(token)) {
requestContext.setSendZuulResponse(false);
requestContext.setResponseStatusCode(HttpStatus.UNAUTHORIZED.value());
}
return null;
}
}
谷歌guava限流
package net.xdclass.apigateway.filter;
import com.google.common.util.concurrent.RateLimiter;
import com.netflix.zuul.ZuulFilter;
import com.netflix.zuul.context.RequestContext;
import com.netflix.zuul.exception.ZuulException;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import javax.servlet.http.HttpServletRequest;
import static org.springframework.cloud.netflix.zuul.filters.support.FilterConstants.PRE_TYPE;
/**
* 订单限流
*/
@Component
public class OrderRateLimiterFilter extends ZuulFilter {
//每秒产生1000个令牌
private static final RateLimiter RATE_LIMITER = RateLimiter.create(1000);
@Override
public String filterType() {
return PRE_TYPE;
}
@Override
public int filterOrder() {
return -4;
}
@Override
public boolean shouldFilter() {
RequestContext requestContext = RequestContext.getCurrentContext();
HttpServletRequest request = requestContext.getRequest();
//只对订单接口限流
if ("/apigateway/order/api/v1/order/save".equalsIgnoreCase(request.getRequestURI())){
return true;
}
return false;
}
@Override
public Object run() throws ZuulException {
RequestContext requestContext = RequestContext.getCurrentContext();
if(!RATE_LIMITER.tryAcquire()){
requestContext.setSendZuulResponse(false);
requestContext.setResponseStatusCode(HttpStatus.TOO_MANY_REQUESTS.value());
}
return null;
}
}
待学内容
- 兰布达表达式
- 如何配置线程池