SpringBoot 2.2和2.3异常处理的一个小变化
2020-08-18 本文已影响0人
Joshua1919
先看个有意思的现象：
@RestController
public class DemoController {
@GetMapping("/hello")
public String hello(){
throw new RuntimeException("服务端异常，请稍后再试！");
}
}
在springboot2.2.0的时候，浏览器访问http://localhost:8080/hello，输出结果如下：
1.png
换成springboot2.3.0的时候，输出结果如下：
2.png
对比一下，能看出来在2.3.0的时候，异常message没有打印出来。
以上是在返回html的时候，返回json的时候，我们再来看下：
public static void main(String[] args)throws Exception {
String url = "http://localhost:8080/hello";
HttpURLConnection conn = (HttpURLConnection)new URL(url).openConnection();
conn.addRequestProperty("Accept", "application/json");
int code = conn.getResponseCode();
System.out.println("responseCode:" + code);
InputStream inputStream = conn.getErrorStream();
String response = readInputStream(inputStream);
System.out.println(response);
}
在2.2.0的时候输出结果是：
{"timestamp":"2020-08-16T04:18:30.778+0000",
"status":500,
"error":"Internal Server Error",
"message":"服务端异常，请稍后再试！",
"path":"/hello"}
在2.3.0的时候输出结果是：
{"timestamp":"2020-08-16T04:16:25.738+00:00",
"status":500,
"error":"Internal Server Error",
"message":"",
"path":"/hello"}
这回看的更清晰了，message字段变成了空。
看下源码的处理，springboot异常处理的入口配置类在这里：ErrorMvcAutoConfiguration，先看2.2.0，它里面配置了处理error的BasicErrorController：
@Bean
@ConditionalOnMissingBean(value = ErrorController.class, search = SearchStrategy.CURRENT)
public BasicErrorController basicErrorController(ErrorAttributes errorAttributes,
ObjectProvider<ErrorViewResolver> errorViewResolvers) {
return new BasicErrorController(errorAttributes, this.serverProperties.getError(),
errorViewResolvers.orderedStream().collect(Collectors.toList()));
}
看下BasicErrorController里面是如何响应error的：
//这个就是生成html页面额
@RequestMapping(produces = MediaType.TEXT_HTML_VALUE)
public ModelAndView errorHtml(HttpServletRequest request, HttpServletResponse response) {
HttpStatus status = getStatus(request);
Map<String, Object> model = Collections
.unmodifiableMap(getErrorAttributes(request, isIncludeStackTrace(request, MediaType.TEXT_HTML)));
response.setStatus(status.value());
ModelAndView modelAndView = resolveErrorView(request, response, status, model);
return (modelAndView != null) ? modelAndView : new ModelAndView("error", model);
}
//这个是输出json的
@RequestMapping
public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
HttpStatus status = getStatus(request);
if (status == HttpStatus.NO_CONTENT) {
return new ResponseEntity<Map<String, Object>>(status);
}
Map<String, Object> body = getErrorAttributes(request, isIncludeStackTrace(request, MediaType.ALL));
return new ResponseEntity<>(body, status);
}
我们主要看下页面上的数据是怎么生成的，也就是getErrorAttributes():
在这之前首先判断了是否要包含异常堆栈isIncludeStackTrace()：
protected boolean isIncludeStackTrace(HttpServletRequest request, MediaType produces) {
IncludeStacktrace include = getErrorProperties().getIncludeStacktrace();
if (include == IncludeStacktrace.ALWAYS) {
return true;
}
if (include == IncludeStacktrace.ON_TRACE_PARAM) {
return getTraceParameter(request);
}
return false;
}
是根据配置项server.error.includeStacktrace来决定的，默认是IncludeStacktrace.NEVER。如果配置了是ALWAYS那就输出堆栈，如果配置了ON_TRACE_PARAM，那么就从请求参数中获取trace参数，如果是true那么也会打印堆栈。
protected Map<String, Object> getErrorAttributes(HttpServletRequest request, boolean includeStackTrace) {
WebRequest webRequest = new ServletWebRequest(request);
return this.errorAttributes.getErrorAttributes(webRequest, includeStackTrace);
}
@Override
public Map<String, Object> getErrorAttributes(WebRequest webRequest, boolean includeStackTrace) {
Map<String, Object> errorAttributes = new LinkedHashMap<>();
//timestamp
errorAttributes.put("timestamp", new Date());
//status
addStatus(errorAttributes, webRequest);
//error和message
addErrorDetails(errorAttributes, webRequest, includeStackTrace);
//path
addPath(errorAttributes, webRequest);
return errorAttributes;
}
这里看到了，这里面包含的内容首先是timestamp，然后是status，最后一行是path，看下addErrorDetails():
private void addErrorDetails(Map<String, Object> errorAttributes, WebRequest webRequest,
boolean includeStackTrace) {
//获取异常，上例中就是RuntimeException
Throwable error = getError(webRequest);
if (error != null) {
while (error instanceof ServletException && error.getCause() != null) {
error = error.getCause();
}
//这个includeException也是个配置项server.error.includeException
// 如果打开就输出exception，值是异常的类名
// 默认是没有打开的，可以看下DefaultErrorAttributes
if (this.includeException) {
errorAttributes.put("exception", error.getClass().getName());
}
// 添加message属性
addErrorMessage(errorAttributes, error);
//是否包含异常堆栈，默认也是没有的
if (includeStackTrace) {
// 添加异常堆栈
addStackTrace(errorAttributes, error);
}
}
Object message = getAttribute(webRequest, "javax.servlet.error.message");
if ((!StringUtils.isEmpty(message) || errorAttributes.get("message") == null)
&& !(error instanceof BindingResult)) {
errorAttributes.put("message", StringUtils.isEmpty(message) ? "No message available" : message);
}
}
private void addErrorMessage(Map<String, Object> errorAttributes, Throwable error) {
BindingResult result = extractBindingResult(error);
//显然这里是null，因此直接直接添加error.getMessage()
if (result == null) {
errorAttributes.put("message", error.getMessage());
return;
}
if (result.hasErrors()) {
errorAttributes.put("errors", result.getAllErrors());
errorAttributes.put("message", "Validation failed for object='" + result.getObjectName()
+ "'. Error count: " + result.getErrorCount());
}
else {
errorAttributes.put("message", "No errors");
}
}
现在我们试着添加下那几个属性，看下输出结果，首先添加server.error.includeStacktrace= IncludeStacktrace.ALWAYS：
3.png
再添加下server.error.includeException=true：
{"timestamp":"2020-08-16T04:56:26.275+0000",
"status":500,
"error":"Internal Server Error",
"exception":"java.lang.RuntimeException",//多了一个这个
"message":"服务端异常，请稍后再试！",
"trace":"java.lang.RuntimeException: 服务端异常，请稍后再试！\r\n\tat com.github.xjs.error.controller.DemoController.hello(DemoController.java:10)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\r\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\r\n\tat java.lang.reflect.Method.invoke(Method.java:498)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)\r\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)\r\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)\r\n\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:634)\r\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:741)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)\r\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)\r\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:526)\r\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)\r\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\r\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)\r\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)\r\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408)\r\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)\r\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:861)\r\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1579)\r\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\r\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\r\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\r\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\r\n\tat java.lang.Thread.run(Thread.java:748)\r\n",
"path":"/hello"}
我们再来看下2.3.0：
@RequestMapping
public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
HttpStatus status = getStatus(request);
if (status == HttpStatus.NO_CONTENT) {
return new ResponseEntity<>(status);
}
Map<String, Object> body = getErrorAttributes(request, getErrorAttributeOptions(request, MediaType.ALL));
return new ResponseEntity<>(body, status);
}
这里的getErrorAttributes之前，首先是getErrorAttributeOptions():
protected ErrorAttributeOptions getErrorAttributeOptions(HttpServletRequest request, MediaType mediaType) {
ErrorAttributeOptions options = ErrorAttributeOptions.defaults();
//server.error.includeException，是否输出异常类名
if (this.errorProperties.isIncludeException()) {
options = options.including(Include.EXCEPTION);
}
//是否打印堆栈，server.error.includeStacktrace= IncludeStacktrace.NEVER
if (isIncludeStackTrace(request, mediaType)) {
options = options.including(Include.STACK_TRACE);
}
//是否输出message
if (isIncludeMessage(request, mediaType)) {
options = options.including(Include.MESSAGE);
}
//和上面是使用的同一个配置项
if (isIncludeBindingErrors(request, mediaType)) {
options = options.including(Include.BINDING_ERRORS);
}
return options;
}
是否输出堆栈，跟2.2.0一样的逻辑：
//server.error.includeStacktrace= IncludeStacktrace.NEVER
protected boolean isIncludeStackTrace(HttpServletRequest request, MediaType produces) {
switch (getErrorProperties().getIncludeStacktrace()) {
case ALWAYS:
return true;
case ON_PARAM:
case ON_TRACE_PARAM:
return getTraceParameter(request);
default:
return false;
}
}
是否输出message：
//添加了一个新的配置项，2.2.0是直接输出的
//server.error.includeMessage=IncludeAttribute.NEVER;
protected boolean isIncludeMessage(HttpServletRequest request, MediaType produces) {
switch (getErrorProperties().getIncludeMessage()) {
case ALWAYS:
return true;
case ON_PARAM:
return getMessageParameter(request);
default:
return false;
}
}
2.3.0新增了一个配置项server.error.includeMessage，默认是NEVER，因此默认是不是输出message的，只要开启就可以了。
当开启以下参数的时候：
server:
error:
includeException: true
includeStacktrace: ALWAYS
includeMessage: ALWAYS
输出结果：
{"timestamp":"2020-08-16T05:09:23.983+00:00",
"status":500,
"error":"Internal Server Error",
"exception":"java.lang.RuntimeException",
"trace":"java.lang.RuntimeException: 服务端异常，请稍后再试！\r\n\tat com.github.xjs.error.controller.DemoController.hello(DemoController.java:10)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)\r\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\r\n\tat java.lang.reflect.Method.invoke(Method.java:498)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)\r\n\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879)\r\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)\r\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)\r\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)\r\n\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:634)\r\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:741)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)\r\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)\r\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202)\r\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)\r\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)\r\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139)\r\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\r\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)\r\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)\r\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373)\r\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)\r\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)\r\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590)\r\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\r\n\tat java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)\r\n\tat java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)\r\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\r\n\tat java.lang.Thread.run(Thread.java:748)\r\n",
"message":"服务端异常，请稍后再试！",
"path":"/hello"}
我们可以模仿BasicErrorController自定义一下异常的处理：
@Controller
@RequestMapping("${server.error.path:${error.path:/error}}")
public class MyErrorController implements ErrorController {
@RequestMapping(produces = MediaType.TEXT_HTML_VALUE)
public ModelAndView errorHtml(HttpServletRequest request, HttpServletResponse response)throws Exception {
response.setContentType("text/html;charset=UTF-8");
response.getWriter().append("服务端异常，请稍后重试");
return null;
}
@RequestMapping
public ResponseEntity<Map<String, Object>> error(HttpServletRequest request) {
Map<String, Object> body = new HashMap<>();
body.put("message", "服务端异常，请稍后重试");
return new ResponseEntity(body, HttpStatus.INTERNAL_SERVER_ERROR);
}
@Override
public String getErrorPath() {
return null;
}
}
参考代码下载：https://github.com/xjs1919/enumdemo 下面的error。
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