Lenient tolerance of unknown HTTP status codes behind RestTemplate

Issue: SPR-15978

Author: jhoeller

spring-web/src/main/java/org/springframework/http/client/ClientHttpResponse.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,13 +38,18 @@ public interface ClientHttpResponse extends HttpInputMessage, Closeable {
 	 * Return the HTTP status code of the response.
 	 * @return the HTTP status as an HttpStatus enum value
 	 * @throws IOException in case of I/O errors
+	 * @throws IllegalArgumentException in case of an unknown HTTP status code
+	 * @see HttpStatus#valueOf(int)
 	 */
 	HttpStatus getStatusCode() throws IOException;
 
 	/**
-	 * Return the HTTP status code of the response as integer
+	 * Return the HTTP status code (potentially non-standard and not
+	 * resolvable through the {@link HttpStatus} enum) as an integer.
 	 * @return the HTTP status as an integer
 	 * @throws IOException in case of I/O errors
+	 * @since 3.1.1
+	 * @see #getStatusCode()
 	 */
 	int getRawStatusCode() throws IOException;
 

spring-web/src/main/java/org/springframework/web/client/AsyncRestTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -513,7 +513,7 @@ private void logResponseStatus(HttpMethod method, URI url, ClientHttpResponse re
 		if (logger.isDebugEnabled()) {
 			try {
 				logger.debug("Async " + method.name() + " request for \"" + url + "\" resulted in " +
-						response.getStatusCode() + " (" + response.getStatusText() + ")");
+						response.getRawStatusCode() + " (" + response.getStatusText() + ")");
 			}
 			catch (IOException ex) {
 				// ignore
@@ -525,7 +525,7 @@ private void handleResponseError(HttpMethod method, URI url, ClientHttpResponse
 		if (logger.isWarnEnabled()) {
 			try {
 				logger.warn("Async " + method.name() + " request for \"" + url + "\" resulted in " +
-						response.getStatusCode() + " (" + response.getStatusText() + "); invoking error handler");
+						response.getRawStatusCode() + " (" + response.getStatusText() + "); invoking error handler");
 			}
 			catch (IOException ex) {
 				// ignore

spring-web/src/main/java/org/springframework/web/client/DefaultResponseErrorHandler.java

@@ -48,6 +48,21 @@ public boolean hasError(ClientHttpResponse response) throws IOException {
 		return hasError(getHttpStatusCode(response));
 	}
 
+	/**
+	 * Template method called from {@link #hasError(ClientHttpResponse)}.
+	 * <p>The default implementation checks if the given status code is
+	 * {@link HttpStatus.Series#CLIENT_ERROR CLIENT_ERROR} or
+	 * {@link HttpStatus.Series#SERVER_ERROR SERVER_ERROR}.
+	 * Can be overridden in subclasses.
+	 * @param statusCode the HTTP status code
+	 * @return {@code true} if the response has an error; {@code false} otherwise
+	 * @see #getHttpStatusCode(ClientHttpResponse)
+	 */
+	protected boolean hasError(HttpStatus statusCode) {
+		return (statusCode.series() == HttpStatus.Series.CLIENT_ERROR ||
+				statusCode.series() == HttpStatus.Series.SERVER_ERROR);
+	}
+
 	/**
 	 * This default implementation throws a {@link HttpClientErrorException} if the response status code
 	 * is {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR}, a {@link HttpServerErrorException}
@@ -89,33 +104,6 @@ protected HttpStatus getHttpStatusCode(ClientHttpResponse response) throws IOExc
 		}
 	}
 
-	/**
-	 * Template method called from {@link #hasError(ClientHttpResponse)}.
-	 * <p>The default implementation checks if the given status code is
-	 * {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR CLIENT_ERROR}
-	 * or {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR SERVER_ERROR}.
-	 * Can be overridden in subclasses.
-	 * @param statusCode the HTTP status code
-	 * @return {@code true} if the response has an error; {@code false} otherwise
-	 * @see #getHttpStatusCode(ClientHttpResponse)
-	 */
-	protected boolean hasError(HttpStatus statusCode) {
-		return (statusCode.series() == HttpStatus.Series.CLIENT_ERROR ||
-				statusCode.series() == HttpStatus.Series.SERVER_ERROR);
-	}
-
-	/**
-	 * Determine the charset of the response (for inclusion in a status exception).
-	 * @param response the response to inspect
-	 * @return the associated charset, or {@code null} if none
-	 * @since 4.3.8
-	 */
-	protected Charset getCharset(ClientHttpResponse response) {
-		HttpHeaders headers = response.getHeaders();
-		MediaType contentType = headers.getContentType();
-		return (contentType != null ? contentType.getCharset() : null);
-	}
-
 	/**
 	 * Read the body of the given response (for inclusion in a status exception).
 	 * @param response the response to inspect
@@ -133,4 +121,16 @@ protected byte[] getResponseBody(ClientHttpResponse response) {
 		return new byte[0];
 	}
 
+	/**
+	 * Determine the charset of the response (for inclusion in a status exception).
+	 * @param response the response to inspect
+	 * @return the associated charset, or {@code null} if none
+	 * @since 4.3.8
+	 */
+	protected Charset getCharset(ClientHttpResponse response) {
+		HttpHeaders headers = response.getHeaders();
+		MediaType contentType = headers.getContentType();
+		return (contentType != null ? contentType.getCharset() : null);
+	}
+
 }

spring-web/src/main/java/org/springframework/web/client/MessageBodyClientHttpResponseWrapper.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,7 +31,7 @@
  *
  * @author Brian Clozel
  * @since 4.1.5
- * @see <a href="http://tools.ietf.org/html/rfc7230#section-3.3.3">rfc7230 Section 3.3.3</a>
+ * @see <a href="http://tools.ietf.org/html/rfc7230#section-3.3.3">RFC 7230 Section 3.3.3</a>
  */
 class MessageBodyClientHttpResponseWrapper implements ClientHttpResponse {
 
@@ -56,12 +56,17 @@ public MessageBodyClientHttpResponseWrapper(ClientHttpResponse response) throws
 	 * @throws IOException in case of I/O errors
 	 */
 	public boolean hasMessageBody() throws IOException {
-		HttpStatus responseStatus = this.getStatusCode();
-		if (responseStatus.is1xxInformational() || responseStatus == HttpStatus.NO_CONTENT ||
-				responseStatus == HttpStatus.NOT_MODIFIED) {
-			return false;
+		try {
+			HttpStatus responseStatus = getStatusCode();
+			if (responseStatus.is1xxInformational() || responseStatus == HttpStatus.NO_CONTENT ||
+					responseStatus == HttpStatus.NOT_MODIFIED) {
+				return false;
+			}
+		}
+		catch (IllegalArgumentException ex) {
+			// Ignore - unknown HTTP status code...
 		}
-		else if (this.getHeaders().getContentLength() == 0) {
+		if (getHeaders().getContentLength() == 0) {
 			return false;
 		}
 		return true;

spring-web/src/main/java/org/springframework/web/client/RestTemplate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -583,7 +583,7 @@ public <T> ResponseEntity<T> exchange(URI url, HttpMethod method, HttpEntity<?>
 	public <T> ResponseEntity<T> exchange(RequestEntity<?> requestEntity, Class<T> responseType)
 			throws RestClientException {
 
-		Assert.notNull(requestEntity, "'requestEntity' must not be null");
+		Assert.notNull(requestEntity, "RequestEntity must not be null");
 
 		RequestCallback requestCallback = httpEntityCallback(requestEntity, responseType);
 		ResponseExtractor<ResponseEntity<T>> responseExtractor = responseEntityExtractor(responseType);
@@ -594,7 +594,7 @@ public <T> ResponseEntity<T> exchange(RequestEntity<?> requestEntity, Class<T> r
 	public <T> ResponseEntity<T> exchange(RequestEntity<?> requestEntity, ParameterizedTypeReference<T> responseType)
 			throws RestClientException {
 
-		Assert.notNull(requestEntity, "'requestEntity' must not be null");
+		Assert.notNull(requestEntity, "RequestEntity must not be null");
 
 		Type type = responseType.getType();
 		RequestCallback requestCallback = httpEntityCallback(requestEntity, type);

spring-web/src/main/java/org/springframework/web/client/UnknownHttpStatusCodeException.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -37,9 +37,9 @@ public class UnknownHttpStatusCodeException extends RestClientResponseException
 	 * {@link HttpStatus}, status text, and response body content.
 	 * @param rawStatusCode the raw status code value
 	 * @param statusText the status text
-	 * @param responseHeaders the response headers, may be {@code null}
-	 * @param responseBody the response body content, may be {@code null}
-	 * @param responseCharset the response body charset, may be {@code null}
+	 * @param responseHeaders the response headers (may be {@code null})
+	 * @param responseBody the response body content (may be {@code null})
+	 * @param responseCharset the response body charset (may be {@code null})
 	 */
 	public UnknownHttpStatusCodeException(int rawStatusCode, String statusText,
 			HttpHeaders responseHeaders, byte[] responseBody, Charset responseCharset) {

spring-websocket/src/main/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransport.java

@@ -37,6 +37,7 @@
 import org.springframework.web.client.ResponseExtractor;
 import org.springframework.web.client.RestOperations;
 import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.UnknownHttpStatusCodeException;
 import org.springframework.web.socket.CloseStatus;
 import org.springframework.web.socket.TextMessage;
 import org.springframework.web.socket.WebSocketHandler;
@@ -205,14 +206,22 @@ public XhrReceiveExtractor(XhrClientSockJsSession sockJsSession) {
 
 		@Override
 		public Object extractData(ClientHttpResponse response) throws IOException {
-			if (!HttpStatus.OK.equals(response.getStatusCode())) {
-				throw new HttpServerErrorException(response.getStatusCode());
+			try {
+				if (!HttpStatus.OK.equals(response.getStatusCode())) {
+					throw new HttpServerErrorException(response.getStatusCode());
+				}
+			}
+			catch (IllegalArgumentException ex) {
+				throw new UnknownHttpStatusCodeException(
+						response.getRawStatusCode(), response.getStatusText(), response.getHeaders(), null, null);
 			}
+
 			if (logger.isTraceEnabled()) {
 				logger.trace("XHR receive headers: " + response.getHeaders());
 			}
 			InputStream is = response.getBody();
 			ByteArrayOutputStream os = new ByteArrayOutputStream();
+
 			while (true) {
 				if (this.sockJsSession.isDisconnected()) {
 					if (logger.isDebugEnabled()) {

spring-websocket/src/test/java/org/springframework/web/socket/sockjs/client/RestTemplateXhrTransportTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2017 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -26,7 +26,6 @@
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.LinkedBlockingDeque;
 
-import org.junit.Before;
 import org.junit.Test;
 
 import org.springframework.core.task.SyncTaskExecutor;
@@ -67,13 +66,7 @@ public class RestTemplateXhrTransportTests {
 
 	private static final Jackson2SockJsMessageCodec CODEC = new Jackson2SockJsMessageCodec();
 
-	private WebSocketHandler webSocketHandler;
-
-
-	@Before
-	public void setup() throws Exception {
-		this.webSocketHandler = mock(WebSocketHandler.class);
-	}
+	private final WebSocketHandler webSocketHandler = mock(WebSocketHandler.class);
 
 
 	@Test