2 * ========================LICENSE_START=================================
5 * Copyright (C) 2019 AT&T Intellectual Property and Nokia
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 * ========================LICENSE_END===================================
20 package org.oransc.ric.portal.dashboard.controller;
22 import java.lang.invoke.MethodHandles;
24 import org.oransc.ric.portal.dashboard.model.ErrorTransport;
25 import org.slf4j.Logger;
26 import org.slf4j.LoggerFactory;
27 import org.springframework.http.HttpStatus;
28 import org.springframework.http.ResponseEntity;
29 import org.springframework.web.bind.annotation.ControllerAdvice;
30 import org.springframework.web.bind.annotation.ExceptionHandler;
31 import org.springframework.web.client.HttpStatusCodeException;
32 import org.springframework.web.context.request.WebRequest;
33 import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
36 * Catches Http status code exceptions and builds a response with code 502 and
37 * some details wrapped in an ErrorTransport object. This factors out try-catch
38 * blocks in many controller methods.
40 * Why 502? I quote: <blockquote>HTTP server received an invalid response from a
41 * server it consulted when acting as a proxy or gateway.</blockquote>
43 * This class and the methods are not strictly necessary, the
44 * SimpleErrorController is invoked when any controller method takes an uncaught
45 * exception, but this approach provides a better response to the front end and
46 * doesn't signal internal server error.
49 * https://www.baeldung.com/exception-handling-for-rest-with-spring
50 * https://www.springboottutorial.com/spring-boot-exception-handling-for-rest-services
53 public class CustomResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {
55 // Superclass has "logger" that is exposed here, so use a different name
56 private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
59 * Generates the response when a REST controller method takes an
60 * HttpStatusCodeException. Confusingly, the container first redirects to /error
62 * {@link org.oransc.ric.portal.dashboard.controller.SimpleErrorController}
63 * method, and that response arrives here as the response body.
69 * @return A response entity with status code 502 plus some details in the body.
71 @ExceptionHandler(HttpStatusCodeException.class)
72 public final ResponseEntity<ErrorTransport> handleHttpStatusCodeException(HttpStatusCodeException ex,
74 log.warn("Request {} failed, status code {}", request.getDescription(false), ex.getStatusCode());
75 return new ResponseEntity<>(new ErrorTransport(ex.getRawStatusCode(), ex.getResponseBodyAsString(), ex),
76 HttpStatus.BAD_GATEWAY);