Foreword
Last week (2020.02.12) we wrote an article on "Spring Cloud Alibaba V2.2.0 release" characteristics related, v2.2.0is based on the Spring Cloud Hoxtonversion. The following summarize the Spring Cloud Alibaba v2.1.0upgrade to v2.2.0the problems encountered.
The main issues involved sentinelin the issue.
Destructive, not backward compatible
Spring Cloud Alibaba SentinelNo longer dependent on sentinel-web-servletimplementation, but rather rely on sentinel-spring-webmvc-dapterSpring-based Interceptorinterceptors resources, instead CommonFilter.
Downgrade policy modification
Found that implements the interface changes
// 之前版本
public class PigxUrlBlockHandler implements UrlBlockHandler {
@Override
public void blocked(HttpServletRequest request, HttpServletResponse response, BlockException e) throws IOException {
// 降级业务处理
}
}
// v2.2.0
public class PigxUrlBlockHandler implements BlockExceptionHandler {
@Override
public void handle(HttpServletRequest request, HttpServletResponse response, BlockException e) throws Exception {
// 降级业务处理
}
}复制代码Request parser
The package implements the interface changes
//旧版本
import com.alibaba.csp.sentinel.adapter.servlet.callback.RequestOriginParser;
// v2.2.0
import com.alibaba.csp.sentinel.adapter.spring.webmvc.callback.RequestOriginParser;
// 请求解析器实现
public class PigxHeaderRequestOriginParser implements RequestOriginParser {
private static final String ALLOW = "Allow";
@Override
public String parseOrigin(HttpServletRequest request) {
return request.getHeader(ALLOW);
}
}复制代码By default, only interception /*request
Mentioned above V2.2.0is based on the Interceptorrealization, the default rule for the interception /*, which is the only request URI is /, / a sentinel request can be processed, dashboardit will only display the intercepted resource, need to configure blocking rules. This issue has been submitted to us pull requestfix Modify the sentinelInterceptor default interception rule and backward
spring:
cloud:
sentinel:
filter:
url-patterns: /**复制代码Involved Source: SentinelWebAutoConfiguration.addInterceptors()
Default: spring boot admindisplayed as part of the service down, the console will display only part of the service
Access Services IP:PORT/actuator/healthdisplay sentinel state down, by default sentinel is lazy loaded at startup will not immediately to sentinel-serversend heartbeat, leading to SentinelHealthIndicatora state ruled false, leading to Spring Boot Adminread actuatorinformationdown
Hunger can be set to load, it will be loaded at startup to load, and send the heartbeat
spring:
cloud:
sentinel:
eager: true复制代码Source can refer: SentinelAutoConfiguration.init()by SPIloading a corresponding service
to sum up
Spring Cloud Alibaba SentinelSource module, the processing logic read relatively straightforward recommendations. The core is the initialization sentinelof dapter, and injected the default demotion or the like.