SpringCloud微服务框架一套就够（下集）
Posted 摸鱼打酱油
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了SpringCloud微服务框架一套就够（下集）相关的知识，希望对你有一定的参考价值。
个人简介
作者是一个来自河源的大三在校生，以下笔记都是作者自学之路的一些浅薄经验，如有错误请指正，将来会不断的完善笔记，帮助更多的Java爱好者入门。
文章目录
Spring Cloud Netflix
断路器springcloud Hystrix
服务降级
在springcloud-02-comsumer-openFeign-dept80的Pom.xml
<!-- Hystrix-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>
修改它的deptController
@RestController
public class deptController
@Autowired
private deptService deptService;
@HystrixCommand(fallbackMethod = "queryAllDept_Hystrix",commandProperties =
@HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds",value = "1500") //添加超时服务降级
)
@RequestMapping("/feign/queryAllDept")
public List<dept> queryAllDept(String id)
int i = Integer.parseInt(id);
if(i<0)
throw new RuntimeException(); //此处为了触发服务降级fallback
return deptService.queryAllDept();
//服务降级方法，这个方法直接从上面的正常方法复制过来，把名字修改一下即可，参数类型也和正常的方法要一致
public List<dept> queryAllDept_Hystrix(String id)
List<dept> depts = deptService.queryAllDept();
depts.add(new dept("1000","Hystrix_fallback"));
return depts;
主启动类
@SpringBootApplication
@EnableFeignClients
@EnableHystrix //开启Hystrix功能
public class springApplicationFeign80
public static void main(String[] args)
SpringApplication.run(springApplicationFeign80.class,args);
commandProperties支持什么参数属性
我们全局搜索HystrixCommandProperties，往下翻可以看到如下
protected HystrixCommandProperties(HystrixCommandKey key, HystrixCommandProperties.Setter builder, String propertyPrefix)
this.key = key;
this.circuitBreakerEnabled = getProperty(propertyPrefix, key, "circuitBreaker.enabled", builder.getCircuitBreakerEnabled(), default_circuitBreakerEnabled);
this.circuitBreakerRequestVolumeThreshold = getProperty(propertyPrefix, key, "circuitBreaker.requestVolumeThreshold", builder.getCircuitBreakerRequestVolumeThreshold(), default_circuitBreakerRequestVolumeThreshold);
this.circuitBreakerSleepWindowInMilliseconds = getProperty(propertyPrefix, key, "circuitBreaker.sleepWindowInMilliseconds", builder.getCircuitBreakerSleepWindowInMilliseconds(), default_circuitBreakerSleepWindowInMilliseconds);
this.circuitBreakerErrorThresholdPercentage = getProperty(propertyPrefix, key, "circuitBreaker.errorThresholdPercentage", builder.getCircuitBreakerErrorThresholdPercentage(), default_circuitBreakerErrorThresholdPercentage);
this.circuitBreakerForceOpen = getProperty(propertyPrefix, key, "circuitBreaker.forceOpen", builder.getCircuitBreakerForceOpen(), default_circuitBreakerForceOpen);
this.circuitBreakerForceClosed = getProperty(propertyPrefix, key, "circuitBreaker.forceClosed", builder.getCircuitBreakerForceClosed(), default_circuitBreakerForceClosed);
this.executionIsolationStrategy = getProperty(propertyPrefix, key, "execution.isolation.strategy", builder.getExecutionIsolationStrategy(), default_executionIsolationStrategy);
this.executionTimeoutInMilliseconds = getProperty(propertyPrefix, key, "execution.isolation.thread.timeoutInMilliseconds", builder.getExecutionIsolationThreadTimeoutInMilliseconds(), default_executionTimeoutInMilliseconds);
this.executionTimeoutEnabled = getProperty(propertyPrefix, key, "execution.timeout.enabled", builder.getExecutionTimeoutEnabled(), default_executionTimeoutEnabled);
this.executionIsolationThreadInterruptOnTimeout = getProperty(propertyPrefix, key, "execution.isolation.thread.interruptOnTimeout", builder.getExecutionIsolationThreadInterruptOnTimeout(), default_executionIsolationThreadInterruptOnTimeout);
this.executionIsolationThreadInterruptOnFutureCancel = getProperty(propertyPrefix, key, "execution.isolation.thread.interruptOnFutureCancel", builder.getExecutionIsolationThreadInterruptOnFutureCancel(), default_executionIsolationThreadInterruptOnFutureCancel);
this.executionIsolationSemaphoreMaxConcurrentRequests = getProperty(propertyPrefix, key, "execution.isolation.semaphore.maxConcurrentRequests", builder.getExecutionIsolationSemaphoreMaxConcurrentRequests(), default_executionIsolationSemaphoreMaxConcurrentRequests);
this.fallbackIsolationSemaphoreMaxConcurrentRequests = getProperty(propertyPrefix, key, "fallback.isolation.semaphore.maxConcurrentRequests", builder.getFallbackIsolationSemaphoreMaxConcurrentRequests(), default_fallbackIsolationSemaphoreMaxConcurrentRequests);
this.fallbackEnabled = getProperty(propertyPrefix, key, "fallback.enabled", builder.getFallbackEnabled(), default_fallbackEnabled);
this.metricsRollingStatisticalWindowInMilliseconds = getProperty(propertyPrefix, key, "metrics.rollingStats.timeInMilliseconds", builder.getMetricsRollingStatisticalWindowInMilliseconds(), default_metricsRollingStatisticalWindow);
this.metricsRollingStatisticalWindowBuckets = getProperty(propertyPrefix, key, "metrics.rollingStats.numBuckets", builder.getMetricsRollingStatisticalWindowBuckets(), default_metricsRollingStatisticalWindowBuckets);
this.metricsRollingPercentileEnabled = getProperty(propertyPrefix, key, "metrics.rollingPercentile.enabled", builder.getMetricsRollingPercentileEnabled(), default_metricsRollingPercentileEnabled);
this.metricsRollingPercentileWindowInMilliseconds = getProperty(propertyPrefix, key, "metrics.rollingPercentile.timeInMilliseconds", builder.getMetricsRollingPercentileWindowInMilliseconds(), default_metricsRollingPercentileWindow);
this.metricsRollingPercentileWindowBuckets = getProperty(propertyPrefix, key, "metrics.rollingPercentile.numBuckets", builder.getMetricsRollingPercentileWindowBuckets(), default_metricsRollingPercentileWindowBuckets);
this.metricsRollingPercentileBucketSize = getProperty(propertyPrefix, key, "metrics.rollingPercentile.bucketSize", builder.getMetricsRollingPercentileBucketSize(), default_metricsRollingPercentileBucketSize);
this.metricsHealthSnapshotIntervalInMilliseconds = getProperty(propertyPrefix, key, "metrics.healthSnapshot.intervalInMilliseconds", builder.getMetricsHealthSnapshotIntervalInMilliseconds(), default_metricsHealthSnapshotIntervalInMilliseconds);
this.requestCacheEnabled = getProperty(propertyPrefix, key, "requestCache.enabled", builder.getRequestCacheEnabled(), default_requestCacheEnabled);
this.requestLogEnabled = getProperty(propertyPrefix, key, "requestLog.enabled", builder.getRequestLogEnabled(), default_requestLogEnabled);
this.executionIsolationThreadPoolKeyOverride = HystrixPropertiesChainedProperty.forString().add(propertyPrefix + ".command." + key.name() + ".threadPoolKeyOverride", (Object)null).build();
例如：超时降级execution.isolation.thread.timeoutInMilliseconds和服务熔断的circuitBreaker.enabled和circuitBreaker.requestVolumeThreshold等等都在上面可以找到
全局服务降级
实现全局服务降级主要就是靠@DefaultProperties和@HystrixCommand
进入@DefaultProperties
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Inherited
@Documented
public @interface DefaultProperties
String groupKey() default "";
String threadPoolKey() default "";
HystrixProperty[] commandProperties() default ;
HystrixProperty[] threadPoolProperties() default ;
Class<? extends Throwable>[] ignoreExceptions() default ;
HystrixException[] raiseHystrixExceptions() default ;
String defaultFallback() default "";
使用方法：这个注解加到消费者的controller层上，必要配置（defaultFallback）也就是默认服务降级方法名称，然后在需要使用默认服务降级的方法上加上@HystrixCommand（不加任何参数）即可
**小坑：注意=======>默认服务降级的方法也就是defaultFallback方法“”不能有任何参数“”，不然就会报错**
比如如下配置
@RestController
@DefaultProperties(defaultFallback = "queryAllDept_Hystrix") //默认全局服务降级，也就是配置上去后，需要服务降级的方法加上@HystrixCommand不加参数即可
public class deptController
@Autowired
private deptService deptService;
// @HystrixCommand(fallbackMethod = "queryAllDept_Hystrix",commandProperties =
// @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds",value = "1500")
// )
@HystrixCommand //触发全局服务降级
@RequestMapping("/feign/queryAllDept")
public List<dept> queryAllDept(String id)
int i = Integer.parseInt(id);
if(i<0)
throw new RuntimeException();
return deptService.queryAllDept(id);
// //服务降级方法,全局服务降级方法不能有参数
public List<dept> queryAllDept_Hystrix()
List<dept> depts = new ArrayList<>();
depts.add(new dept("1000","Hystrix_fallback"));
return depts;
服务熔断
Pom.xml
<!-- Hystrix-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
</dependency>
在springcloud-02-provider-dept8001和8002的controller
@RestController
public class deptController
private deptService deptService;
@Value("$server.port")
private String port;
@Autowired
@Qualifier("deptServiceImpl")
public void setDeptService(com.boot.service.deptService deptService)
this.deptService = deptService;
@GetMapping(path = "/queryAllDept")
@HystrixCommand(fallbackMethod = "queryAllDept_Hystrix",commandProperties =
@HystrixProperty(name = "circuitBreaker.enabled",value = "true"),
@HystrixProperty(name = "circuitBreaker.requestVolumeThreshold",value = "10"),
@HystrixProperty(name = "circuitBreaker.sleepWindowInMilliseconds",value = "20000"),//注意这是毫秒。1秒=1000毫秒
@HystrixProperty(name = "circuitBreaker.errorThresholdPercentage",value = "50")
)
public List<dept> queryAllDept(String id)
List<dept> depts = deptService.queryAllDept();
depts.add(new dept("999",port));
// try
// Thread.sleep(1500);
// catch (InterruptedException e)
// e.printStackTrace();
//
if(Integer.parseInt(id)<0)
throw new RuntimeException();
return depts;
/**
* 服务熔断
*/
public List<dept> queryAllDept_Hystrix(String id)
List<dept> depts = deptService.queryAllDept();
depts.add(new dept("1066","Break"));
return depts;
提供者主启动类：
@SpringBootApplication
@EnableEurekaClient //eureka客户端
@EnableCircuitBreaker //开启服务熔断功能
public class SpringBootApplication8001
public static void main(String[] args)
SpringApplication.run(SpringBootApplication8001.class,args);
Hystrix-Dashboard
创建子模块springcloud-02-hystrix-Dashboard8110
仪表盘的访问页面：
假如端口号是8110：http://localhost:8110/hystrix
Pom.xml
<dependencies>
<!-- web和actuator是必备的，******除了gateway网关不能加入web包 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- actuator用来监控-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<!-- Hystrix-dashboard-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
</dependency>
</dependencies>
配置文件没有要求，就修改端口号即可
server:
port: 8110
spring:
application:
name: hystrixDashboard8110
主启动类：
@SpringBootApplication
@EnableHystrixDashboard //开启了Hystrix仪表盘功能
public class springBootApplication8110
public static void main(String[] args)
SpringApplication.run(springBootApplication8110.class,args);
Bug：Hystrix仪表盘连接不上
解决方法：在每一个需要监控的模块（比如微服务提供者8001和8002）加上如下配置
1.微服务提供者的Pom.xml
<!-- Hystrix-dashboard（微服务提供者）-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-hystrix-dashboard</artifactId>
</dependency>
2.在微服务提供者8001和8002加上一个bean
@SpringBootApplication
@EnableEurekaClient //eureka客户端
@EnableCircuitBreaker //开启服务熔断功能
public class SpringBootApplication8001
public static void main(String[] args)
SpringApplication.run(SpringBootApplication8001.class,args);
//解决Hystrix-dashboard连接不上
@Bean
public ServletRegistrationBean getServlet()
HystrixMetricsStreamServlet streamServlet = new HystrixMetricsStreamServlet();
ServletRegistrationBean registrationBean = new ServletRegistrationBean(streamServlet);
registrationBean.setLoadOnStartup(1);
registrationBean.addUrlMappings("/hystrix.stream");
registrationBean.setName("HystrixMetricsStreamServlet");
return registrationBean;
Bug：Hystrix仪表盘一直是loading
解决方法：用openFeign去调用一下即可
成功页面👇
服务网关springcloud gateway
小坑：1.注意===》gateWay不能有springBoot-Web的启动器，不然会报错。。。。。。。。
小坑（负载均衡）：2.注意==》需要把gateway当作提供者注册到注册中心eureka中，不然不能进行服务网关的负载均衡
服务网关gateway作用：把所有请求都先进入网关gateway，再由gateway进行分发请求，这样的好处就是隐藏分发到的微服务的端口号，安全性更高
配置gateway服务网关
1.创建子模块springcloud-02-gateWay9527
2.打开pom.xml，添加依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-gateway</artifactId>
</dependency>
3.application.yml
server:
port: SSM详细的过程，一套就够了