春@ExceptionHandler返回錯誤代碼的HTTPStatus

Question

TL; DR：調用HttpServletResponse.getStatus & HttpStatus.valueOf(HttpServletResponse.getStatus)).name()時@ExceptionHandler函數返回200 OK而不是400 Bad Request爲MissingServletParameterException。 MissingServletParameterException僅作爲示例使用，其他例外情況也會發生。

你好，

我遇到的問題是，我想Raygun（崩潰報告系統）與我們的Java /春季啓動應用程序集成。我發現最簡單的方法是創建一個會顯示錯誤信息給用戶，以及將異常傳遞到Raygun自定義異常處理程序。

本來，我試圖實施這裏建議用我自己的Raygun實現增加https://spring.io/blog/2013/11/01/exception-handling-in-spring-mvc

@ControllerAdvice 
class GlobalDefaultExceptionHandler { 
    public static final String DEFAULT_ERROR_VIEW = "error"; 

    private static ApiAccessToken accessToken = new ApiAccessToken(); 
    private static String databaseName = null; 

    @ExceptionHandler(value = Exception.class) 
    public ModelAndView 
    defaultErrorHandler(HttpServletRequest req, Exception e) throws Exception { 
    // If the exception is annotated with @ResponseStatus rethrow it and let 
    // the framework handle it 
    if (AnnotationUtils.findAnnotation(e.getClass(), ResponseStatus.class) != null) { 
     throw e; 
    } 

    // Otherwise setup and send the user to a default error-view. 
    ModelAndView mav = new ModelAndView(); 
    mav.addObject("exception", e); 
    mav.addObject("url", req.getRequestURL()); 
    mav.setViewName(DEFAULT_ERROR_VIEW); 

    // Display the error message to the user, and send the exception to Raygun along with any user details provided. 
    RaygunClient client = new RaygunClient("<MyRaygunAPIKey>"); 

    if (accessToken.getUsername() != null && accessToken.getDatabaseName() != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("username: " + accessToken.getUsername()); 
     tags.add("database: " + accessToken.getDatabaseName()); 
     client.Send(e, tags); 
     accessToken = null; 
     return mav; 

    } else if (databaseName != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("database: " + databaseName); 
     client.Send(e, tags); 
     databaseName = null; 
     return mav; 

    } else { 
     client.Send(e); 
     return mav; 
    } 
} 

我這個遇到的問題是，我們有公共和私有API端點。私有API端點用於我們的iOS應用程序，而公共API端點沒有前端。它們旨在讓企業能夠融入自己的系統（PowerBI，郵差，定製集成等）。所以沒有可以使用ModelAndView重定向到的視圖。

相反，我已經決定做的是不是使用的ModelAndView，我只是在已格式化模仿Spring的默認JSON的錯誤消息的字符串。

@ExceptionHandler(value = Exception.class) 
public @ResponseBody String defaultErrorHandler(HttpServletRequest req, HttpServletResponse resp, Exception e) throws Exception { 

    // Create a customised error message that imitates the Spring default Json error message 
    StringBuilder sb = new StringBuilder("{ \n") 
      .append(" \"timestamp\": ").append("\"").append(DateTime.now().toString()).append("\" \n") 
      .append(" \"status\": ").append(resp.getStatus()).append(" \n") 
      .append(" \"error\": ").append("\"").append(HttpStatus.valueOf(resp.getStatus()).name()).append("\" \n") 
      .append(" \"exception\": ").append("\"").append(e.getClass().toString().substring(6)).append("\" \n") 
      .append(" \"message\": ").append("\"").append(e.getMessage()).append("\" \n") 
      .append(" \"path\": ").append("\"").append(req.getServletPath()).append("\" \n") 
      .append("}"); 

    String errorMessage = String.format(sb.toString()); 

    // Display the error message to the user, and send the exception to Raygun along with any user details provided. 
    RaygunClient client = new RaygunClient("<MyRaygunAPIKey>"); 

    if (accessToken.getUsername() != null && accessToken.getDatabaseName() != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("username: " + accessToken.getUsername()); 
     tags.add("database: " + accessToken.getDatabaseName()); 
     client.Send(e, tags); 
     accessToken = null; 
     return errorMessage; 

    } else if (databaseName != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("database: " + databaseName); 
     client.Send(e, tags); 
     databaseName = null; 
     return errorMessage; 

    } else { 
     client.Send(e); 
     return errorMessage; 
    } 
} 

與此唯一的問題是，當我故意導致異常被拋出，它的200 OK HTTP狀態這顯然是不正確的返回。

例如，這是defaultErrorHandler()註釋掉（發送沒什麼Raygun）：

{ 
"timestamp": "2017-07-18T02:59:45.131+0000", 
"status": 400, 
"error": "Bad Request", 
"exception": 
"org.springframework.web.bind.MissingServletRequestParameterException", 
"message": "Required String parameter ‘foo’ is not present", 
"path": "/api/foo/bar/v1" 
} 

而這與它沒有被註釋掉（發送例外Raygun）：

{ 
"timestamp": "2017-07-25T06:21:53.895Z" 
"status": 200 
"error": "OK" 
"exception": "org.springframework.web.bind.MissingServletRequestParameterException" 
"message": "Required String parameter 'foo' is not present" 
"path": "/api/foo/bar/V1" 
} 

任何幫助或建議我做錯了將不勝感激。感謝您的時間。

Answer 1

我還無法確定何時正被拋出的異常爲什麼它返回一個200 OK狀態。但我意識到我與試圖創建模仿Spring的默認json的錯誤信息字符串做，是過​​於複雜，沒有必要的。

一旦我將異常發送給Raygun，我可以重新拋出異常並讓框架像處理使用@ResponseStatus註釋的異常一樣處理異常。

@ExceptionHandler(value = Exception.class) 
public void defaultErrorHandler(Exception e) throws Exception { 

    RaygunClient client = new RaygunClient("<MyRaygunAPIKey>"); 

    // If the exception is annotated with @ResponseStatus rethrow it and let 
    // the framework handle it 
    if (AnnotationUtils.findAnnotation(e.getClass(), ResponseStatus.class) != null) { 
     throw e; 
    } 

    // Otherwise send the exception Raygun and then rethrow it and let the framework handle it 
    if (accessToken.getUsername() != null && accessToken.getDatabaseName() != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("username: " + accessToken.getUsername()); 
     tags.add("database: " + accessToken.getDatabaseName()); 
     client.Send(e, tags); 
     accessToken = null; 
     throw e; 

    } else if (databaseName != null) { 
     ArrayList tags = new ArrayList<String>(); 
     tags.add("database: " + databaseName); 
     client.Send(e, tags); 
     databaseName = null; 
     throw e; 

    } else { 
     client.Send(e); 
     throw e; 
    } 
} 

裸露的骨頭implentation應該是這樣的：

@ExceptionHandler(value = Exception.class) 
public void defaultErrorHandler(Exception e) throws Exception { 

    RaygunClient client = new RaygunClient("<MyRaygunAPIKey>"); 

    // If the exception is annotated with @ResponseStatus rethrow it and let the framework handle it 
    if (AnnotationUtils.findAnnotation(e.getClass(), ResponseStatus.class) != null) { 
     throw e; 
    } 
    // Otherwise send the exception Raygun and then rethrow it and let the framework handle it 
    else { 
     client.Send(e); 
     throw e; 
    } 
} 

Answer 2

在您的控制器建議嘗試這種方式異常類型映射到Http-Status如下：

if (ex instanceof MyException) 
{//just an example. 
    return new ResponseEntity<>(e, HttpStatus.BAD_REQUEST); 
} 
else 
{//all other unhandled exceptions 
    return new ResponseEntity<>(e, HttpStatus.INTERNAL_SERVER_ERROR); 
} 

這裏MyException是例外的，你在運行時拋出的類型。假設我正在處理錯誤的請求。