/*
* Copyright 2011 Esri.
*
* 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 com.esri.gpt.control.webharvest.client.thredds;
import com.esri.gpt.framework.http.HttpClientRequest;
import com.esri.gpt.framework.http.ResponseInfo;
import com.esri.gpt.framework.http.StringHandler;
import com.esri.gpt.framework.resource.query.Criteria;
import com.esri.gpt.framework.util.Val;
import java.io.IOException;
import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.httpclient.Header;
import org.apache.commons.httpclient.util.DateParseException;
import org.apache.commons.httpclient.util.DateUtil;
/**
* THREDDS proxy.
*/
class TProxy {
/** logger */
private static final Logger LOGGER = Logger.getLogger(TProxy.class.getCanonicalName());
/** service info */
private TInfo info;
/** criteria */
private Criteria criteria;
/**
* Creates instance of the proxy.
* @param info service info
* @param criteria criteria
*/
public TProxy(TInfo info, Criteria criteria) {
if (info == null) {
throw new IllegalArgumentException("No info provided.");
}
this.info = info;
this.criteria = criteria;
}
public Content readContent(String sourceUri) throws IOException {
LOGGER.log(Level.FINER, "Reading metadata of source URI: \"{0}\" through proxy: {1}", new Object[]{sourceUri, this});
sourceUri = Val.chkStr(sourceUri).replaceAll("\\{", "%7B").replaceAll("\\}", "%7D");
HttpClientRequest cr = new HttpClientRequest();
cr.setBatchHttpClient(this.info.getBatchHttpClient());
cr.setUrl(sourceUri);
BreakableStringHandler sh = new BreakableStringHandler(criteria != null ? criteria.getFromDate() : null);
cr.setContentHandler(sh);
cr.execute();
String mdText = sh.getContent();
LOGGER.log(Level.FINER, "Received metadata of source URI: \"{0}\" through proxy: {1}", new Object[]{sourceUri, this});
LOGGER.finest(mdText);
return new Content(sh.getLastModifiedDate(), mdText);
}
public String read(String sourceUri) throws IOException {
LOGGER.log(Level.FINER, "Reading metadata of source URI: \"{0}\" through proxy: {1}", new Object[]{sourceUri, this});
sourceUri = Val.chkStr(sourceUri).replaceAll("\\{", "%7B").replaceAll("\\}", "%7D");
HttpClientRequest cr = new HttpClientRequest();
cr.setBatchHttpClient(this.info.getBatchHttpClient());
cr.setUrl(sourceUri);
StringHandler sh = new StringHandler();
cr.setContentHandler(sh);
cr.execute();
String mdText = sh.getContent();
LOGGER.log(Level.FINER, "Received metadata of source URI: \"{0}\" through proxy: {1}", new Object[]{sourceUri, this});
LOGGER.finest(mdText);
return mdText;
}
@Override
public String toString() {
return info.toString();
}
/**
* Finds last modified date.
* @param headers array of headers
* @return last modified date or <code>null</code> if date not found
*/
private static Date findLastModifiedDate(ResponseInfo responseInfo) {
Header lastModfiedHeader = responseInfo.getResponseHeader("Last-Modified");
if (lastModfiedHeader != null) {
try {
return DateUtil.parseDate(lastModfiedHeader.getValue());
} catch (DateParseException ex) {
return null;
}
}
return null;
}
/**
* Content
*/
public static class Content {
private Date lastModifiedDate;
private String text;
/**
* Creates instance of the content
* @param lastModifiedDate last modified date
* @param text text read from stream
*/
public Content(Date lastModifiedDate, String text) {
this.lastModifiedDate = lastModifiedDate;
this.text = text;
}
/**
* Gets last modified date
* @return last modified date or <code>null</code> if last modified date not available
*/
public Date getLastModifedDate() {
return lastModifiedDate;
}
/**
* Gets text.
* @return text
*/
public String getText() {
return text;
}
}
private static class BreakableStringHandler extends StringHandler {
private Date fromDate;
private Date lastModifiedDate;
public BreakableStringHandler(Date fromDate) {
this.fromDate = fromDate;
}
public Date getLastModifiedDate() {
return lastModifiedDate;
}
@Override
public boolean onBeforeReadResponse(HttpClientRequest request) {
lastModifiedDate = findLastModifiedDate(request.getResponseInfo());
if (fromDate!=null && lastModifiedDate!=null && lastModifiedDate.before(fromDate)) {
return false;
}
else {
return true;
}
}
}
}