Wrap RestTemplate extractor exceptions in RestClientExceptions

When using a `RestTemplate` instance within a Spring MVC application,
client exceptions may propagate in the MVC stack and can be wrongly
mapped by server `ExceptionHandlers`, leading to a wrong HTTP response
sent to the MVC client.

The `RestTemplate` instance uses `HttpMessageConverter` to decode
the remote service responses; and when those fail decoding an HTTP
response, they can throw an `HttpMessageNotReadableException`. That
exception then bubbles up through the `HttpMessageConverterExtractor`,
`RestTemplate` and the whole MVC stack, later mapped to HTTP 400
responses, since those exceptions can also be throws by the server stack
when the incoming requests can't be deserialized.

This commit wraps all `IOException` and `HttpMessageNotReadableException`
instances thrown by the extractor into `RestClientException`` instances.
It's now easier to consistently handle client exceptions and avoid such
edge cases.

Issue: SPR-13592
This commit is contained in:
Brian Clozel
2016-08-26 17:56:00 +02:00
parent 7fdb892042
commit b84fefc430
2 changed files with 79 additions and 29 deletions

View File

@@ -1,5 +1,5 @@
/*
* Copyright 2002-2015 the original author or authors.
* Copyright 2002-2016 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.
@@ -27,6 +27,7 @@ import org.springframework.http.MediaType;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.http.converter.GenericHttpMessageConverter;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.HttpMessageNotReadableException;
import org.springframework.util.Assert;
/**
@@ -84,27 +85,34 @@ public class HttpMessageConverterExtractor<T> implements ResponseExtractor<T> {
}
MediaType contentType = getContentType(responseWrapper);
for (HttpMessageConverter<?> messageConverter : this.messageConverters) {
if (messageConverter instanceof GenericHttpMessageConverter) {
GenericHttpMessageConverter<?> genericMessageConverter = (GenericHttpMessageConverter<?>) messageConverter;
if (genericMessageConverter.canRead(this.responseType, null, contentType)) {
if (logger.isDebugEnabled()) {
logger.debug("Reading [" + this.responseType + "] as \"" +
contentType + "\" using [" + messageConverter + "]");
try {
for (HttpMessageConverter<?> messageConverter : this.messageConverters) {
if (messageConverter instanceof GenericHttpMessageConverter) {
GenericHttpMessageConverter<?> genericMessageConverter =
(GenericHttpMessageConverter<?>) messageConverter;
if (genericMessageConverter.canRead(this.responseType, null, contentType)) {
if (logger.isDebugEnabled()) {
logger.debug("Reading [" + this.responseType + "] as \"" +
contentType + "\" using [" + messageConverter + "]");
}
return (T) genericMessageConverter.read(this.responseType, null, responseWrapper);
}
}
if (this.responseClass != null) {
if (messageConverter.canRead(this.responseClass, contentType)) {
if (logger.isDebugEnabled()) {
logger.debug("Reading [" + this.responseClass.getName() + "] as \"" +
contentType + "\" using [" + messageConverter + "]");
}
return (T) messageConverter.read((Class) this.responseClass, responseWrapper);
}
return (T) genericMessageConverter.read(this.responseType, null, responseWrapper);
}
}
if (this.responseClass != null) {
if (messageConverter.canRead(this.responseClass, contentType)) {
if (logger.isDebugEnabled()) {
logger.debug("Reading [" + this.responseClass.getName() + "] as \"" +
contentType + "\" using [" + messageConverter + "]");
}
return (T) messageConverter.read((Class) this.responseClass, responseWrapper);
}
}
}
catch(IOException | HttpMessageNotReadableException exc) {
throw new RestClientException("Error while extracting response for type ["
+ this.responseType + "] and content type [" + contentType + "]", exc);
}
throw new RestClientException("Could not extract response: no suitable HttpMessageConverter found " +
"for response type [" + this.responseType + "] and content type [" + contentType + "]");