[FIXED] Thymeleaf + SpringBoot : show errors in Errors page

Issue

I have a SpringBoot v2.3.7.RELEASE with Thymeleaf. I've created this template to see the Errors, but I don't see any exceptions in the source code when there is an exception in the app:

    <div class="jumbotron text-center">

        <h1>Uh-oh! Something Happened!</h1>
        <!--  As we are using Thymeleaf, you might consider using
              ${#httpServletRequest.requestURL}. But that returns the path
              to this error page.  Hence we explicitly add the url to the
              Model in some of the example code. -->
        <p th:if="${url}">
            <b>Page:</b> <span th:text="${url}">Page URL</span>
        </p>

        <p th:if="${timestamp}" id='created'>
            <b>Occurred:</b> <span th:text="${timestamp}">Timestamp</span>
        </p>


        <p>Support may ask you to right click to view page source.</p>

        <!--
          // Hidden Exception Details  - this is not a recommendation, but here is
          // how you hide an exception in the page using Thymeleaf
          -->
        <div th:utext="'&lt;!--'" th:remove="tag"></div>
        <div th:utext="'Failed URL: ' +  ${url}" th:remove="tag">${url}</div>
        <div th:utext="'Exception: ' + ${exception}" th:remove="tag">${exception}</div>
        <ul th:remove="tag">
            <li th:each="ste : ${exception}" th:remove="tag"><span
                    th:utext="${ste}" th:remove="tag">${ste}</span></li>
        </ul>
        <div th:utext="'--&gt;'" th:remove="tag"></div>

    </div>

</div>

and the controller:

@Controller
public class MyErrorController implements ErrorController {

    private final static String PATH = "/error";

    @RequestMapping(PATH)
    public String getErrorPath() {
        return "error/genericError";
    }


}

Solution

1. Spring Boot by default provides /error mapping where all exception/errors are forwarded. In case of Thymeleaf (or other template engines), we can map errors to a global custom template file by name 'error' under src/main/resources/templates/ directory.

2. enable the stacktrace to be included as expression attribute to the Thymeleaf view:

   server.error.include-stacktrace=always

Answered By - en Peris