java.lang.IllegalStateException : No instances available for student-service at org. springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient

Question

我正在运行链接中的Spring Cloud Consule示例:: https://howtodoinjava.com/spring/spring-cloud/consul-service-registration-discovery/ 。当我运行http://localhost:8098/getSchoolDetails/abcschool时我收到以下错误，客户端似乎无法识别student-service。

java.lang.IllegalStateException: No instances available for student-service
    at org.springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient.execute(RibbonLoadBalancerClient.java:75) ~[spring-cloud-netflix-core-1.3.1.RELEASE.jar:1.3.1.RELEASE]
    at org.springframework.cloud.client.loadbalancer.LoadBalancerInterceptor.intercept(LoadBalancerInterceptor.java:55) ~[spring-cloud-commons-1.2.2.RELEASE.jar:1.2.2.RELEASE]
    at org.springframework.http.client.InterceptingClientHttpRequest$InterceptingRequestExecution.execute(InterceptingClientHttpRequest.java:86) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.cloud.netflix.metrics.MetricsClientHttpRequestInterceptor.intercept(MetricsClientHttpRequestInterceptor.java:64) ~[spring-cloud-netflix-core-1.3.1.RELEASE.jar:1.3.1.RELEASE]
    at org.springframework.http.client.InterceptingClientHttpRequest$InterceptingRequestExecution.execute(InterceptingClientHttpRequest.java:86) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.http.client.InterceptingClientHttpRequest.executeInternal(InterceptingClientHttpRequest.java:70) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:652) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:613) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:559) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at com.example.howtodoinjava.springcloudconsulschool.delegate.StudentServiceDelegate.callStudentServiceAndGetData(StudentServiceDelegate.java:22) ~[classes/:na]
    at com.example.howtodoinjava.springcloudconsulschool.controller.SchoolServiceController.getStudents(SchoolServiceController.java:21) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_161]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_161]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_161]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_161]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.boot.web.filter.ApplicationContextHeaderFilter.doFilterInternal(ApplicationContextHeaderFilter.java:55) ~[spring-boot-1.5.4.RELEASE.jar:1.5.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:110) ~[spring-boot-actuator-1.5.4.RELEASE.jar:1.5.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106) ~[spring-boot-actuator-1.5.4.RELEASE.jar:1.5.4.RELEASE]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) ~[tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) [na:1.8.0_161]
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [na:1.8.0_161]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.15.jar:8.5.15]
    at java.lang.Thread.run(Unknown Source) [na:1.8.0_161]

当我检查实例时，这两个服务都在 Consul 中注册:http://localhost:8500/ui

StudentServiceDelegate

@Service
public class StudentServiceDelegate {
    @Autowired
    private RestTemplate restTemplate;

    public String callStudentServiceAndGetData(String schoolname) {
        System.out.println("Consul Demo - Getting School details for " + schoolname);
        String URL = "http://student-service/getStudentDetailsForSchool/{schoolname}";

        String response = restTemplate.exchange(URL, HttpMethod.GET, null, new ParameterizedTypeReference<String>() {}, schoolname).getBody();


        System.out.println("Response Received as " + response + " -  " + new Date());

        return "School Name -  " + schoolname + " :::  Student Details " + response + " -  " + new Date();
    }

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }
}

在上面的 Controller 中，当调用剩余调用时，它失败了。

SchoolServiceController

@RestController
public class SchoolServiceController {

    @Autowired
    StudentServiceDelegate studentServiceDelegate;

    @RequestMapping(value = "/getSchoolDetails/{schoolname}", method = RequestMethod.GET)
    public String getStudents(@PathVariable String schoolname) {
        System.out.println("Going to call student service to get data!");

        return studentServiceDelegate.callStudentServiceAndGetData(schoolname);
    }
}

application.properties

server.port=8098
spring.application.name=school-service
management.security.enabled=false

添加了 SH-1

添加了 SH-2

Get http://XXXX.com:8098/health: dial tcp 10.142.167.39:8098: connectex: No connection could be made because the target machine actively refused it.

当我点击时http://localhost:9098/health ，我收到以下错误。

{
    "status": "DOWN",
    "discoveryComposite": {
        "description": "Spring Cloud Consul Discovery Client",
        "status": "UP",
        "discoveryClient": {
            "description": "Spring Cloud Consul Discovery Client",
            "status": "UP",
            "services": [
                "consul",
                "school-service",
                "student-service"
            ]
        }
    },
    "diskSpace": {
        "status": "UP",
        "total": 511584497664,
        "free": 336424210432,
        "threshold": 10485760
    },
    "refreshScope": {
        "status": "UP"
    },
    "consul": {
        "status": "DOWN",
        "services": {
            "consul": [],
            "school-service": [],
            "student-service": []
        },
        "error": "java.lang.IllegalArgumentException: Value must not be null"
    },
    "hystrix": {
        "status": "UP"
    }
}

Answer 1

我能够按照此链接解决此问题:https://github.com/indrabasak/spring-consul-example/blob/master/client/README.md ，我们应该严格使用以下属性以避免出现以下错误。

management.security.enabled=false
management.health.consul.enabled=false

http://localhost:8098//getSchoolDetails/abcschool

我得到的输出是::

School Name - abcschool ::: Student Details [{"name":"Sajal","className":"Class IV"},{"name":"Lokesh","className":"Class V"}] - Thu Apr 12 15:47:53 IST 2018