org.springframework.boot.autoconfigure.web.reactive.error.AbstractErrorWebExceptionHandler Maven / Gradle / Ivy
/*
* Copyright 2012-2020 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.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.boot.autoconfigure.web.reactive.error;
import java.util.Collections;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.logging.Log;
import reactor.core.publisher.Mono;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.boot.autoconfigure.template.TemplateAvailabilityProviders;
import org.springframework.boot.autoconfigure.web.WebProperties.Resources;
import org.springframework.boot.web.error.ErrorAttributeOptions;
import org.springframework.boot.web.error.ErrorAttributeOptions.Include;
import org.springframework.boot.web.reactive.error.ErrorAttributes;
import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
import org.springframework.context.ApplicationContext;
import org.springframework.core.NestedExceptionUtils;
import org.springframework.core.io.Resource;
import org.springframework.core.log.LogMessage;
import org.springframework.http.HttpLogging;
import org.springframework.http.HttpStatus;
import org.springframework.http.codec.HttpMessageReader;
import org.springframework.http.codec.HttpMessageWriter;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.StringUtils;
import org.springframework.web.reactive.function.BodyInserters;
import org.springframework.web.reactive.function.server.RouterFunction;
import org.springframework.web.reactive.function.server.ServerRequest;
import org.springframework.web.reactive.function.server.ServerResponse;
import org.springframework.web.reactive.result.view.ViewResolver;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.util.HtmlUtils;
/**
* Abstract base class for {@link ErrorWebExceptionHandler} implementations.
*
* @author Brian Clozel
* @author Scott Frederick
* @since 2.0.0
* @see ErrorAttributes
*/
public abstract class AbstractErrorWebExceptionHandler implements ErrorWebExceptionHandler, InitializingBean {
/**
* Currently duplicated from Spring WebFlux HttpWebHandlerAdapter.
*/
private static final Set DISCONNECTED_CLIENT_EXCEPTIONS;
static {
Set exceptions = new HashSet<>();
exceptions.add("AbortedException");
exceptions.add("ClientAbortException");
exceptions.add("EOFException");
exceptions.add("EofException");
DISCONNECTED_CLIENT_EXCEPTIONS = Collections.unmodifiableSet(exceptions);
}
private static final Log logger = HttpLogging.forLogName(AbstractErrorWebExceptionHandler.class);
private final ApplicationContext applicationContext;
private final ErrorAttributes errorAttributes;
private final Resources resources;
private final TemplateAvailabilityProviders templateAvailabilityProviders;
private List> messageReaders = Collections.emptyList();
private List> messageWriters = Collections.emptyList();
private List viewResolvers = Collections.emptyList();
/**
* Create a new {@code AbstractErrorWebExceptionHandler}.
* @param errorAttributes the error attributes
* @param resourceProperties the resource properties
* @param applicationContext the application context
* @deprecated since 2.4.0 in favor of
* {@link #AbstractErrorWebExceptionHandler(ErrorAttributes, Resources, ApplicationContext)}
*/
@Deprecated
public AbstractErrorWebExceptionHandler(ErrorAttributes errorAttributes,
org.springframework.boot.autoconfigure.web.ResourceProperties resourceProperties,
ApplicationContext applicationContext) {
this(errorAttributes, (Resources) resourceProperties, applicationContext);
}
/**
* Create a new {@code AbstractErrorWebExceptionHandler}.
* @param errorAttributes the error attributes
* @param resources the resources configuration properties
* @param applicationContext the application context
* @since 2.4.0
*/
public AbstractErrorWebExceptionHandler(ErrorAttributes errorAttributes, Resources resources,
ApplicationContext applicationContext) {
Assert.notNull(errorAttributes, "ErrorAttributes must not be null");
Assert.notNull(resources, "Resources must not be null");
Assert.notNull(applicationContext, "ApplicationContext must not be null");
this.errorAttributes = errorAttributes;
this.resources = resources;
this.applicationContext = applicationContext;
this.templateAvailabilityProviders = new TemplateAvailabilityProviders(applicationContext);
}
/**
* Configure HTTP message writers to serialize the response body with.
* @param messageWriters the {@link HttpMessageWriter}s to use
*/
public void setMessageWriters(List> messageWriters) {
Assert.notNull(messageWriters, "'messageWriters' must not be null");
this.messageWriters = messageWriters;
}
/**
* Configure HTTP message readers to deserialize the request body with.
* @param messageReaders the {@link HttpMessageReader}s to use
*/
public void setMessageReaders(List> messageReaders) {
Assert.notNull(messageReaders, "'messageReaders' must not be null");
this.messageReaders = messageReaders;
}
/**
* Configure the {@link ViewResolver} to use for rendering views.
* @param viewResolvers the list of {@link ViewResolver}s to use
*/
public void setViewResolvers(List viewResolvers) {
this.viewResolvers = viewResolvers;
}
/**
* Extract the error attributes from the current request, to be used to populate error
* views or JSON payloads.
* @param request the source request
* @param includeStackTrace whether to include the error stacktrace information
* @return the error attributes as a Map
* @deprecated since 2.3.0 in favor of
* {@link #getErrorAttributes(ServerRequest, ErrorAttributeOptions)}
*/
@Deprecated
protected Map getErrorAttributes(ServerRequest request, boolean includeStackTrace) {
return getErrorAttributes(request,
(includeStackTrace) ? ErrorAttributeOptions.of(Include.STACK_TRACE) : ErrorAttributeOptions.defaults());
}
/**
* Extract the error attributes from the current request, to be used to populate error
* views or JSON payloads.
* @param request the source request
* @param options options to control error attributes
* @return the error attributes as a Map
*/
protected Map getErrorAttributes(ServerRequest request, ErrorAttributeOptions options) {
return this.errorAttributes.getErrorAttributes(request, options);
}
/**
* Extract the original error from the current request.
* @param request the source request
* @return the error
*/
protected Throwable getError(ServerRequest request) {
return this.errorAttributes.getError(request);
}
/**
* Check whether the trace attribute has been set on the given request.
* @param request the source request
* @return {@code true} if the error trace has been requested, {@code false} otherwise
*/
protected boolean isTraceEnabled(ServerRequest request) {
return getBooleanParameter(request, "trace");
}
/**
* Check whether the message attribute has been set on the given request.
* @param request the source request
* @return {@code true} if the message attribute has been requested, {@code false}
* otherwise
*/
protected boolean isMessageEnabled(ServerRequest request) {
return getBooleanParameter(request, "message");
}
/**
* Check whether the errors attribute has been set on the given request.
* @param request the source request
* @return {@code true} if the errors attribute has been requested, {@code false}
* otherwise
*/
protected boolean isBindingErrorsEnabled(ServerRequest request) {
return getBooleanParameter(request, "errors");
}
private boolean getBooleanParameter(ServerRequest request, String parameterName) {
String parameter = request.queryParam(parameterName).orElse("false");
return !"false".equalsIgnoreCase(parameter);
}
/**
* Render the given error data as a view, using a template view if available or a
* static HTML file if available otherwise. This will return an empty
* {@code Publisher} if none of the above are available.
* @param viewName the view name
* @param responseBody the error response being built
* @param error the error data as a map
* @return a Publisher of the {@link ServerResponse}
*/
protected Mono renderErrorView(String viewName, ServerResponse.BodyBuilder responseBody,
Map error) {
if (isTemplateAvailable(viewName)) {
return responseBody.render(viewName, error);
}
Resource resource = resolveResource(viewName);
if (resource != null) {
return responseBody.body(BodyInserters.fromResource(resource));
}
return Mono.empty();
}
private boolean isTemplateAvailable(String viewName) {
return this.templateAvailabilityProviders.getProvider(viewName, this.applicationContext) != null;
}
private Resource resolveResource(String viewName) {
for (String location : this.resources.getStaticLocations()) {
try {
Resource resource = this.applicationContext.getResource(location);
resource = resource.createRelative(viewName + ".html");
if (resource.exists()) {
return resource;
}
}
catch (Exception ex) {
// Ignore
}
}
return null;
}
/**
* Render a default HTML "Whitelabel Error Page".
*
* Useful when no other error view is available in the application.
* @param responseBody the error response being built
* @param error the error data as a map
* @return a Publisher of the {@link ServerResponse}
*/
protected Mono renderDefaultErrorView(ServerResponse.BodyBuilder responseBody,
Map error) {
StringBuilder builder = new StringBuilder();
Date timestamp = (Date) error.get("timestamp");
Object message = error.get("message");
Object trace = error.get("trace");
Object requestId = error.get("requestId");
builder.append("Whitelabel Error Page
")
.append("This application has no configured error view, so you are seeing this as a fallback.
")
.append("").append(timestamp).append("").append("[").append(requestId)
.append("] There was an unexpected error (type=").append(htmlEscape(error.get("error")))
.append(", status=").append(htmlEscape(error.get("status"))).append(").");
if (message != null) {
builder.append("").append(htmlEscape(message)).append("");
}
if (trace != null) {
builder.append("").append(htmlEscape(trace)).append("");
}
builder.append("");
return responseBody.bodyValue(builder.toString());
}
private String htmlEscape(Object input) {
return (input != null) ? HtmlUtils.htmlEscape(input.toString()) : null;
}
@Override
public void afterPropertiesSet() throws Exception {
if (CollectionUtils.isEmpty(this.messageWriters)) {
throw new IllegalArgumentException("Property 'messageWriters' is required");
}
}
/**
* Create a {@link RouterFunction} that can route and handle errors as JSON responses
* or HTML views.
*
* If the returned {@link RouterFunction} doesn't route to a {@code HandlerFunction},
* the original exception is propagated in the pipeline and can be processed by other
* {@link org.springframework.web.server.WebExceptionHandler}s.
* @param errorAttributes the {@code ErrorAttributes} instance to use to extract error
* information
* @return a {@link RouterFunction} that routes and handles errors
*/
protected abstract RouterFunction getRoutingFunction(ErrorAttributes errorAttributes);
@Override
public Mono handle(ServerWebExchange exchange, Throwable throwable) {
if (exchange.getResponse().isCommitted() || isDisconnectedClientError(throwable)) {
return Mono.error(throwable);
}
this.errorAttributes.storeErrorInformation(throwable, exchange);
ServerRequest request = ServerRequest.create(exchange, this.messageReaders);
return getRoutingFunction(this.errorAttributes).route(request).switchIfEmpty(Mono.error(throwable))
.flatMap((handler) -> handler.handle(request))
.doOnNext((response) -> logError(request, response, throwable))
.flatMap((response) -> write(exchange, response));
}
private boolean isDisconnectedClientError(Throwable ex) {
return DISCONNECTED_CLIENT_EXCEPTIONS.contains(ex.getClass().getSimpleName())
|| isDisconnectedClientErrorMessage(NestedExceptionUtils.getMostSpecificCause(ex).getMessage());
}
private boolean isDisconnectedClientErrorMessage(String message) {
message = (message != null) ? message.toLowerCase() : "";
return (message.contains("broken pipe") || message.contains("connection reset by peer"));
}
/**
* Logs the {@code throwable} error for the given {@code request} and {@code response}
* exchange. The default implementation logs all errors at debug level. Additionally,
* any internal server error (500) is logged at error level.
* @param request the request that was being handled
* @param response the response that was being sent
* @param throwable the error to be logged
* @since 2.2.0
*/
protected void logError(ServerRequest request, ServerResponse response, Throwable throwable) {
if (logger.isDebugEnabled()) {
logger.debug(request.exchange().getLogPrefix() + formatError(throwable, request));
}
if (HttpStatus.resolve(response.rawStatusCode()) != null
&& response.statusCode().equals(HttpStatus.INTERNAL_SERVER_ERROR)) {
logger.error(LogMessage.of(() -> String.format("%s 500 Server Error for %s",
request.exchange().getLogPrefix(), formatRequest(request))), throwable);
}
}
private String formatError(Throwable ex, ServerRequest request) {
String reason = ex.getClass().getSimpleName() + ": " + ex.getMessage();
return "Resolved [" + reason + "] for HTTP " + request.methodName() + " " + request.path();
}
private String formatRequest(ServerRequest request) {
String rawQuery = request.uri().getRawQuery();
String query = StringUtils.hasText(rawQuery) ? "?" + rawQuery : "";
return "HTTP " + request.methodName() + " \"" + request.path() + query + "\"";
}
private Mono write(ServerWebExchange exchange, ServerResponse response) {
// force content-type since writeTo won't overwrite response header values
exchange.getResponse().getHeaders().setContentType(response.headers().getContentType());
return response.writeTo(exchange, new ResponseContext());
}
private class ResponseContext implements ServerResponse.Context {
@Override
public List> messageWriters() {
return AbstractErrorWebExceptionHandler.this.messageWriters;
}
@Override
public List viewResolvers() {
return AbstractErrorWebExceptionHandler.this.viewResolvers;
}
}
}