/*
* Copyright (c) 2009, 2010, 2011, 2012, B3log Team
*
* 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.b3log.latke.urlfetch.local;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletResponse;
import org.b3log.latke.urlfetch.HTTPHeader;
import org.b3log.latke.urlfetch.HTTPRequest;
import org.b3log.latke.urlfetch.HTTPResponse;
/**
* Common handler for URL fetch.
*
* match {@link org.b3log.latke.servlet.HTTPRequestMethod}<br>GET, HEAD</br>
* the core method is {@link #doFetch(HTTPRequest)}
*
* @author <a href="mailto:wmainlove@gmail.com">Love Yao</a>
* @author <a href="mailto:DL88250@gmail.com">Liang Ding</a>
* @version 1.0.0.4, May 4, 2012
*
*/
class UrlFetchCommonHandler {
/**
* doFetch- the template method.
*
* @see #prepareConnection(HTTPRequest)
* @see #configConnection(HttpURLConnection, HTTPRequest)
* @see #resultConnection(HttpURLConnection)
*
* @param request the specified request
* @return {@link HTTPResponse}
* @throws IOException IOException from java.net
*/
protected HTTPResponse doFetch(final HTTPRequest request) throws IOException {
final HttpURLConnection httpURLConnection = prepareConnection(request);
configConnection(httpURLConnection, request);
httpURLConnection.connect();
final HTTPResponse ret = resultConnection(httpURLConnection);
httpURLConnection.disconnect();
return ret;
}
/**
*
* @param request the specified HTTP request
* @return {@link HttpURLConnection}
* @throws IOException IOException from java.net
*/
protected HttpURLConnection prepareConnection(final HTTPRequest request) throws IOException {
if (request.getURL() == null) {
throw new IOException("URL for URLFetch should not be null");
}
final HttpURLConnection ret = (HttpURLConnection) request.getURL().openConnection();
ret.setRequestMethod(request.getRequestMethod().toString());
for (HTTPHeader httpHeader : request.getHeaders()) {
// XXX set or add
ret.setRequestProperty(httpHeader.getName(), httpHeader.getValue());
}
// Properties prop = System.getProperties();
// prop.setProperty("http.proxyHost", "10.1.2.188");
// prop.setProperty("http.proxyPort", "80");
// prop.setProperty("https.proxyHost", "10.1.2.188");
// prop.setProperty("https.proxyPort", "80");
return ret;
}
/**
*
* @param httpURLConnection {@link HttpURLConnection}
* @param request the specified HTTP request
* @throws IOException IOException from java.net
*/
protected void configConnection(final HttpURLConnection httpURLConnection, final HTTPRequest request)
throws IOException {
}
/**
*
* @param httpURLConnection {@link HttpURLConnection}
* @return HTTPResponse the http response
* @throws IOException IOException from java.net
*/
protected HTTPResponse resultConnection(final HttpURLConnection httpURLConnection) throws IOException {
final HTTPResponse ret = new HTTPResponse();
ret.setResponseCode(httpURLConnection.getResponseCode());
ret.setFinalURL(httpURLConnection.getURL());
InputStream retStream;
if (HttpServletResponse.SC_OK == ret.getResponseCode()) {
retStream = httpURLConnection.getInputStream();
} else {
retStream = httpURLConnection.getErrorStream();
}
ret.setContent(inputStreamToByte(retStream));
fillHttpResponseHeader(ret, httpURLConnection.getHeaderFields());
return ret;
}
/**
*
* @param httpResponse HTTP Rsponse
* @param headerFields headerFiedls in HTTP response
*/
protected void fillHttpResponseHeader(final HTTPResponse httpResponse, final Map<String, List<String>> headerFields) {
for (Map.Entry<String, List<String>> entry : headerFields.entrySet()) {
httpResponse.addHeader(new HTTPHeader(entry.getKey(), entry.getValue().toString()));
}
}
/**
*
* @param is {@link InputStream}
* @return Byte[]
* @throws IOException from java.io
*/
// XXX need to move to 'util'
private byte[] inputStreamToByte(final InputStream is) throws IOException {
final ByteArrayOutputStream bytestream = new ByteArrayOutputStream();
int ch;
while ((ch = is.read()) != -1) {
bytestream.write(ch);
}
final byte[] ret = bytestream.toByteArray();
bytestream.close();
return ret;
}
}