RecentlyChangedPVs.java

package org.epics.archiverappliance.mgmt.bpl.reports;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.LinkedList;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;
import org.epics.archiverappliance.common.BPLAction;
import org.epics.archiverappliance.config.ApplianceInfo;
import org.epics.archiverappliance.config.ConfigService;
import org.epics.archiverappliance.utils.ui.GetUrlContent;
import org.epics.archiverappliance.utils.ui.MimeTypeConstants;
import org.json.simple.JSONArray;

/**
 * Generate a report of PVs that were recently changed.
 * As the lastModifiedTime is also set during creation, this is only those PVs whose creation and modification times are different.
 * 
 * 
 * @epics.BPLAction - Return a list of PVs sorted by descending PVTypeInfo modification timestamp. 
 * @epics.BPLActionParam limit - Limit this report to this many PVs per appliance in the cluster. Optional, if unspecified, there are no limits enforced.
 * @epics.BPLActionEnd
 * 
 * @author mshankar
 *
 */
public class RecentlyChangedPVs implements BPLAction {
	private static Logger logger = Logger.getLogger(RecentlyChangedPVs.class.getName());
	@Override
	public void execute(HttpServletRequest req, HttpServletResponse resp,ConfigService configService) throws IOException {
		String limit = req.getParameter("limit");
		logger.info("Recently changed PVs report for " + (limit == null ? "default limit " : ("limit " + limit)));
		LinkedList<String> recentlyChangedURLs = new LinkedList<String>();
		for(ApplianceInfo info : configService.getAppliancesInCluster()) {
			String mgmtUrl = info.getMgmtURL();
			String recentlyChangedURL = mgmtUrl + "/getRecentlyModifiedPVsForThisInstance";
			if(limit != null) {
				recentlyChangedURL = recentlyChangedURL + "?limit=" + limit;
			}
			recentlyChangedURLs.add(recentlyChangedURL);
		}
		
		JSONArray recentlyChangedPVs = GetUrlContent.combineJSONArrays(recentlyChangedURLs);
		
		resp.setContentType(MimeTypeConstants.APPLICATION_JSON);
		try(PrintWriter out = resp.getWriter()) {
			out.println(recentlyChangedPVs.toJSONString());
		}
	}
}