/*
* Copyright 2014 Netflix, Inc.
*
* 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
*
* http://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 io.reactivex.netty.protocol.http.server;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufOutputStream;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.util.ReferenceCountUtil;
import io.reactivex.netty.RxNetty;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import rx.Observable;
import java.io.PrintStream;
import java.nio.charset.Charset;
/**
* @author Nitesh Kant
*/
class DefaultErrorResponseGenerator<O> implements ErrorResponseGenerator<O> {
private static final Logger logger = LoggerFactory.getLogger(DefaultErrorResponseGenerator.class);
public static final String STACKTRACE_TEMPLATE_VARIABLE = "${stacktrace}";
private static final String ERROR_HTML_TEMPLATE = "<!DOCTYPE html>\n" +
"<html>\n" +
"<head>\n" +
" <title>RxNetty Error Page.</title>\n" +
"</head>\n" +
"<body>\n" +
" <h1>Unexpected error occured in the server.</h1>\n" +
" <h3>Error</h3>\n" +
" <PRE> " + STACKTRACE_TEMPLATE_VARIABLE + " </PRE>\n" +
"</body>\n" +
"</html>";
@Override
public void updateResponse(HttpServerResponse<O> response, Throwable error) {
if (error instanceof HttpError) {
response.setStatus(((HttpError)error).getStatus());
}
else {
response.setStatus(HttpResponseStatus.INTERNAL_SERVER_ERROR);
}
response.getHeaders().set(HttpHeaders.Names.CONTENT_TYPE, "text/html");
ByteBuf buffer = response.getChannel().alloc().buffer(1024);// 1KB initial length.
PrintStream printStream = null;
try {
printStream = new PrintStream(new ByteBufOutputStream(buffer));
error.printStackTrace(printStream);
String errorPage = ERROR_HTML_TEMPLATE.replace(STACKTRACE_TEMPLATE_VARIABLE,
buffer.toString(Charset.defaultCharset()));
response.writeString(errorPage);
} finally {
ReferenceCountUtil.release(buffer);
if (null != printStream) {
try {
printStream.flush();
printStream.close();
} catch (Exception e) {
logger.error("Error closing stream for generating error response stacktrace. This is harmless.", e);
}
}
}
}
public static void main(String[] args) {
RxNetty.createHttpServer(8888, new RequestHandler<ByteBuf, ByteBuf>() {
@Override
public Observable<Void> handle(HttpServerRequest<ByteBuf> request, HttpServerResponse<ByteBuf> response) {
throw new NullPointerException("doomsday");
}
}).startAndWait();
}
}