How to pass error details to model when create a custom error handler?

Question

I created a custom error page to replace the default whitelabel based on this tutorial. It worked fine but I need to pass other attributes to the page so I changed my code to intercept the error endpoint based on the geoand's answer here.

Here is my final code:

@Controller
public class ErroHandlerController implements ErrorController {

    @Value("${terena.midas.location}")
    private String midasLocation;   

    @RequestMapping("/error")
    public String handleError( Model model ) {
        model.addAttribute( "midasLocation", midasLocation );
        return "error";
    }

    @Override
    public String getErrorPath() {
        return "/error";
    }   

}

Well the code worked sending my variable midasLocation but I lost the error details like path, status,message, etc... How can I bring them back again?

Answer 1

You need to use the ErrorAttributes which "provides access to error attributes which can be logged or presented to the user".

Take a look:

• at how the default Spring Error Controller does it: BasicErrorController.java
• LogicBig - Spring Boot - Using ErrorAttributes in our custom ErrorController

Basic functionality:

import org.springframework.boot.web.servlet.error.ErrorAttributes;
import org.springframework.boot.web.servlet.error.ErrorController;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.context.request.WebRequest;

@Controller
public class ErrorHandler implements ErrorController {

   private final ErrorAttributes errorAttributes;

   public ErrorHandler(ErrorAttributes errorAttributes) {
      this.errorAttributes = errorAttributes;
   }

   @GetMapping("/error")
   public String handleError(Model model, WebRequest webRequest) {
      model.addAttribute("midasLocation", "xxx");
      final Throwable error = errorAttributes.getError(webRequest);
      model.addAttribute("exception", error);
      model.addAttribute("message", error == null ? "" : error.getMessage());
      return "error";
   }

   @Override public String getErrorPath() {
      return "/error";
   }

   @GetMapping("/throwErrorForTest")
   public String throwError() {
      throw new RuntimeException("my exception");
   }
}