[spring] Spring Boot Remove Whitelabel Error Page

I'm trying to remove white label error page, so what I've done was created a controller mapping for "/error",

@RestController
public class IndexController {

    @RequestMapping(value = "/error")
    public String error() {
        return "Error handling";
    }

}

But now I"m getting this error.

Exception in thread "AWT-EventQueue-0" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerMapping' defined in class path resource   [org/springframework/web/servlet/config/annotation/DelegatingWebMvcConfiguration.class]: Invocation  of init method failed; nested exception is java.lang.IllegalStateException: Ambiguous mapping found. Cannot map 'basicErrorController' bean method 
public org.springframework.http.ResponseEntity<java.util.Map<java.lang.String, java.lang.Object>>  org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletR equest)
to {[/error],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}: There is already 'indexController' bean method

Don't know whether I'm doing anything wrong. Please advice.

EDIT:

Already added error.whitelabel.enabled=false to application.properties file, still getting the same error

I had a similar issue WhiteLabel Error message on my Angular SPA whenever I did a refresh.

The fix was to create a controller that implements ErrorController but instead of returning a String, I had to return a ModelAndView object that forwards to /

@CrossOrigin
@RestController
public class IndexController implements ErrorController {
    
    private static final String PATH = "/error";
    
    @RequestMapping(value = PATH)
    public ModelAndView saveLeadQuery() {           
        return new ModelAndView("forward:/");
    }

    @Override
    public String getErrorPath() {
        return PATH;
    }
}

Here's an alternative method which is very similar to the "old way" of specifying error mappings in web.xml.

Just add this to your Spring Boot configuration:

@SpringBootApplication
public class Application implements WebServerFactoryCustomizer<ConfigurableServletWebServerFactory> {

    @Override
    public void customize(ConfigurableServletWebServerFactory factory) {
        factory.addErrorPages(new ErrorPage(HttpStatus.FORBIDDEN, "/errors/403.html"));
        factory.addErrorPages(new ErrorPage(HttpStatus.NOT_FOUND, "/errors/404.html"));
        factory.addErrorPages(new ErrorPage("/errors/500.html"));
    }

}

Then you can define the error pages in the static content normally.

The customizer can also be a separate @Component, if desired.

I am using Spring Boot version 2.1.2 and the errorAttributes.getErrorAttributes() signature didn't work for me (in acohen's response). I wanted a JSON type response so I did a little digging and found this method did exactly what I needed.

I got most of my information from this thread as well as this blog post.

First, I created a CustomErrorController that Spring will look for to map any errors to.

package com.example.error;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.web.servlet.error.ErrorAttributes;
import org.springframework.boot.web.servlet.error.ErrorController;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.WebRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.HashMap;
import java.util.Map;

@RestController
public class CustomErrorController implements ErrorController {

    private static final String PATH = "error";

    @Value("${debug}")
    private boolean debug;

    @Autowired
    private ErrorAttributes errorAttributes;

    @RequestMapping(PATH)
    @ResponseBody
    public CustomHttpErrorResponse error(WebRequest request, HttpServletResponse response) {
        return new CustomHttpErrorResponse(response.getStatus(), getErrorAttributes(request));
    }

    public void setErrorAttributes(ErrorAttributes errorAttributes) {
        this.errorAttributes = errorAttributes;
    }

    @Override
    public String getErrorPath() {
        return PATH;
    }

    private Map<String, Object> getErrorAttributes(WebRequest request) {
        Map<String, Object> map = new HashMap<>();
        map.putAll(this.errorAttributes.getErrorAttributes(request, this.debug));
        return map;
    }
}

Second, I created a CustomHttpErrorResponse class to return the error as JSON.

package com.example.error;

import java.util.Map;

public class CustomHttpErrorResponse {

    private Integer status;
    private String path;
    private String errorMessage;
    private String timeStamp;
    private String trace;

    public CustomHttpErrorResponse(int status, Map<String, Object> errorAttributes) {
        this.setStatus(status);
        this.setPath((String) errorAttributes.get("path"));
        this.setErrorMessage((String) errorAttributes.get("message"));
        this.setTimeStamp(errorAttributes.get("timestamp").toString());
        this.setTrace((String) errorAttributes.get("trace"));
    }

    // getters and setters
}

Finally, I had to turn off the Whitelabel in the application.properties file.

server.error.whitelabel.enabled=false

This should even work for xml requests/responses. But I haven't tested that. It did exactly what I was looking for since I was creating a RESTful API and only wanted to return JSON.

With Spring Boot > 1.4.x you could do this:

@SpringBootApplication(exclude = {ErrorMvcAutoConfiguration.class})
public class MyApi {
  public static void main(String[] args) {
    SpringApplication.run(App.class, args);
  }
}

but then in case of exception the servlet container will display its own error page.

In Spring Boot 1.4.1 using Mustache templates, placing error.html under templates folder will be enough:

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="utf-8">
  <title>Error</title>
</head>

<body>
  <h1>Error {{ status }}</h1>
  <p>{{ error }}</p>
  <p>{{ message }}</p>
  <p>{{ path }}</p>
</body>

</html>

Additional variables can be passed by creating an interceptor for /error

If you want a more "JSONish" response page you can try something like that:

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.web.ErrorAttributes;
import org.springframework.boot.autoconfigure.web.ErrorController;
import org.springframework.util.Assert;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.util.Map;

@RestController
@RequestMapping("/error")
public class SimpleErrorController implements ErrorController {

  private final ErrorAttributes errorAttributes;

  @Autowired
  public SimpleErrorController(ErrorAttributes errorAttributes) {
    Assert.notNull(errorAttributes, "ErrorAttributes must not be null");
    this.errorAttributes = errorAttributes;
  }

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

  @RequestMapping
  public Map<String, Object> error(HttpServletRequest aRequest){
     Map<String, Object> body = getErrorAttributes(aRequest,getTraceParameter(aRequest));
     String trace = (String) body.get("trace");
     if(trace != null){
       String[] lines = trace.split("\n\t");
       body.put("trace", lines);
     }
     return body;
  }

  private boolean getTraceParameter(HttpServletRequest request) {
    String parameter = request.getParameter("trace");
    if (parameter == null) {
        return false;
    }
    return !"false".equals(parameter.toLowerCase());
  }

  private Map<String, Object> getErrorAttributes(HttpServletRequest aRequest, boolean includeStackTrace) {
    RequestAttributes requestAttributes = new ServletRequestAttributes(aRequest);
    return errorAttributes.getErrorAttributes(requestAttributes, includeStackTrace);
  }
}

server.error.whitelabel.enabled=false

Include the above line to the Resources folders application.properties

More Error Issue resolve please refer http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-customize-the-whitelabel-error-page

I was trying to call a REST endpoint from a microservice and I was using the resttemplate's put method.

In my design if any error occurred inside the REST endpoint it should return a JSON error response, it was working for some calls but not for this put one, it returned the white label error page instead.

So I did some investigation and I found out that;

Spring try to understand the caller if it is a machine then it returns JSON response or if it is a browser than it returns the white label error page HTML.

As a result: my client app needed to say to REST endpoint that the caller is a machine, not a browser so for this the client app needed to add 'application/json' into the ACCEPT header explicitly for the resttemplate's 'put' method. I added this to the header and solved the problem.

my call to the endpoint:

restTemplate.put(url, request, param1, param2);

for above call I had to add below header param.

headers.set("Accept", MediaType.APPLICATION_JSON_UTF8_VALUE);

or I tried to change put to exchange as well, in this case, exchange call added the same header for me and solved the problem too but I don't know why :)

restTemplate.exchange(....)

Spring Boot by default has a “whitelabel” error page which you can see in a browser if you encounter a server error. Whitelabel Error Page is a generic Spring Boot error page which is displayed when no custom error page is found.

Set “server.error.whitelabel.enabled=false” to switch of the default error page

Spring boot doc 'was' wrong (they have since fixed it) :

To switch it off you can set error.whitelabel.enabled=false

should be

To switch it off you can set server.error.whitelabel.enabled=false

Manual here says that you have to set server.error.whitelabel.enabled to false to disable the standard error page. Maybe it is what you want?

I am experiencing the same error after adding /error mapping, by the way.

This depends on your spring boot version:

When SpringBootVersion <= 1.2 then use error.whitelabel.enabled = false

When SpringBootVersion >= 1.3 then use server.error.whitelabel.enabled = false

You can remove it completely by specifying:

import org.springframework.context.annotation.Configuration;
import org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration;
...
@Configuration
@EnableAutoConfiguration(exclude = {ErrorMvcAutoConfiguration.class})
public static MainApp { ... }

However, do note that doing so will probably cause servlet container's whitelabel pages to show up instead :)

EDIT: Another way to do this is via application.yaml. Just put in the value:

spring:
  autoconfigure:
    exclude: org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration

Documentation

For Spring Boot < 2.0, the class is located in package org.springframework.boot.autoconfigure.web.