/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.blur.thirdparty.thrift_0_9_0.server;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Map;
import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.blur.thirdparty.thrift_0_9_0.TException;
import org.apache.blur.thirdparty.thrift_0_9_0.TProcessor;
import org.apache.blur.thirdparty.thrift_0_9_0.protocol.TProtocol;
import org.apache.blur.thirdparty.thrift_0_9_0.protocol.TProtocolFactory;
import org.apache.blur.thirdparty.thrift_0_9_0.transport.TIOStreamTransport;
import org.apache.blur.thirdparty.thrift_0_9_0.transport.TTransport;
/**
* Servlet implementation class ThriftServer, that allows {@link TProcessor} and
* {@link TProtocolFactory} to be supplied after the {@link #init()} method has
* finished. <br>
* Subclasses must implement the abstract methods that return the TProcessor and
* two TProtocolFactory. Those methods are guaranteed to be called exactly once,
* and that {@link ServletContext} is available.
*/
public abstract class TExtensibleServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private TProcessor processor;
private TProtocolFactory inFactory;
private TProtocolFactory outFactory;
private Collection<Map.Entry<String, String>> customHeaders;
/**
* Returns the appropriate {@link TProcessor}. This will be called <b>once</b> just
* after the {@link #init()} method
*
* @return
*/
protected abstract TProcessor getProcessor();
/**
* Returns the appropriate in {@link TProtocolFactory}. This will be called
* <b>once</b> just after the {@link #init()} method
*
* @return
*/
protected abstract TProtocolFactory getInProtocolFactory();
/**
* Returns the appropriate out {@link TProtocolFactory}. This will be called
* <b>once</b> just after the {@link #init()} method
*
* @return
*/
protected abstract TProtocolFactory getOutProtocolFactory();
@Override
public final void init(ServletConfig config) throws ServletException {
super.init(config); //no-args init() happens here
this.processor = getProcessor();
this.inFactory = getInProtocolFactory();
this.outFactory = getOutProtocolFactory();
this.customHeaders = new ArrayList<Map.Entry<String, String>>();
if (processor == null) {
throw new ServletException("processor must be set");
}
if (inFactory == null) {
throw new ServletException("inFactory must be set");
}
if (outFactory == null) {
throw new ServletException("outFactory must be set");
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
* response)
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
TTransport inTransport = null;
TTransport outTransport = null;
try {
response.setContentType("application/x-thrift");
if (null != this.customHeaders) {
for (Map.Entry<String, String> header : this.customHeaders) {
response.addHeader(header.getKey(), header.getValue());
}
}
InputStream in = request.getInputStream();
OutputStream out = response.getOutputStream();
TTransport transport = new TIOStreamTransport(in, out);
inTransport = transport;
outTransport = transport;
TProtocol inProtocol = inFactory.getProtocol(inTransport);
TProtocol outProtocol = inFactory.getProtocol(outTransport);
processor.process(inProtocol, outProtocol);
out.flush();
} catch (TException te) {
throw new ServletException(te);
}
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
* response)
*/
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doPost(req, resp);
}
public void addCustomHeader(final String key, final String value) {
this.customHeaders.add(new Map.Entry<String, String>() {
public String getKey() {
return key;
}
public String getValue() {
return value;
}
public String setValue(String value) {
return null;
}
});
}
public void setCustomHeaders(Collection<Map.Entry<String, String>> headers) {
this.customHeaders.clear();
this.customHeaders.addAll(headers);
}
}