/**
* Copyright 2007-2015, Kaazing Corporation. All rights reserved.
*
* 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 org.kaazing.k3po.driver.internal.behavior.handler.codec.http;
import static java.lang.String.format;
import static org.jboss.netty.buffer.ChannelBuffers.copiedBuffer;
import static org.jboss.netty.util.CharsetUtil.UTF_8;
import java.util.Iterator;
import java.util.List;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.handler.codec.http.HttpHeaders;
import org.kaazing.k3po.driver.internal.behavior.ScriptProgressException;
import org.kaazing.k3po.driver.internal.behavior.handler.codec.AbstractConfigDecoder;
import org.kaazing.k3po.driver.internal.behavior.handler.codec.MessageDecoder;
import org.kaazing.k3po.driver.internal.netty.bootstrap.http.HttpChannelConfig;
public class HttpTrailerDecoder extends AbstractConfigDecoder {
private String name;
private List<MessageDecoder> valueDecoders;
public HttpTrailerDecoder(String name, List<MessageDecoder> valueDecoders) {
this.name = name;
this.valueDecoders = valueDecoders;
}
@Override
public void decode(Channel channel) throws Exception {
HttpChannelConfig httpConfig = (HttpChannelConfig) channel.getConfig();
HttpHeaders headers = httpConfig.getReadTrailers();
List<String> headerValues = headers.getAll(name);
if (valueDecoders.size() == 1) {
MessageDecoder valueDecoder = valueDecoders.get(0);
decodeTrailerValue(headers, headerValues, valueDecoder);
}
else {
for (MessageDecoder valueDecoder : valueDecoders) {
decodeTrailerValue(headers, headerValues, valueDecoder);
}
}
}
@Override
public String toString() {
return format("http:trailer %s %s", name, valueDecoders);
}
private void decodeTrailerValue(HttpHeaders trailers,
List<String> trailerValues, MessageDecoder valueDecoder)
throws Exception {
int headerValueCount = trailerValues.size();
if (headerValueCount == 0) {
throw new ScriptProgressException(getRegionInfo(), format("Missing HTTP trailer: %s", name));
}
else if (headerValueCount == 1) {
// efficiently handle single-valued HTTP header
String headerValue = trailerValues.get(0);
valueDecoder.decodeLast(copiedBuffer(headerValue, UTF_8));
}
else {
// attempt to match each HTTP trailer value with decoder
// throw last decode failure exception if none match
Exception decodeFailure = null;
for (Iterator<String> $i = trailerValues.iterator(); $i.hasNext();) {
String headerValue = $i.next();
try {
valueDecoder.decodeLast(copiedBuffer(headerValue, UTF_8));
$i.remove();
break;
}
catch (Exception e) {
decodeFailure = e;
}
}
if (trailerValues.size() != headerValueCount) {
trailers.set(name, trailerValues);
}
else {
assert decodeFailure != null;
throw decodeFailure;
}
}
}
}