/*
* Copyright 2014 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
*
* 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 ratpack.http.internal;
import io.netty.handler.codec.http.HttpHeaders;
import ratpack.handling.Context;
import ratpack.handling.Handler;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
public class ContentNegotiationHandler implements Handler {
private final Map<? extends CharSequence, Handler> handlers;
public ContentNegotiationHandler(Map<? extends CharSequence, Handler> handlers) {
this.handlers = handlers;
}
@Override
public void handle(Context context) throws Exception {
if (handlers.isEmpty()) {
context.clientError(406);
return;
}
List<? extends CharSequence> types = new ArrayList<>(handlers.keySet());
CharSequence first = types.get(0);
Collections.reverse(types);
CharSequence winner = first;
String acceptHeader = context.getRequest().getHeaders().get(HttpHeaders.Names.ACCEPT);
if (acceptHeader != null && !acceptHeader.isEmpty()) {
winner = MimeParse.bestMatch(types, acceptHeader);
}
if (winner == null || winner.toString().isEmpty()) {
context.clientError(406);
} else {
context.getResponse().contentType(winner);
Handler handler = handlers.get(winner);
handler.handle(context);
}
}
}