CirmClusterStatisticsStore.java

/*******************************************************************************
 * Copyright 2014 Miami-Dade County
 * 
 * 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.sharegov.cirm.stats;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Date;
import java.util.SortedSet;
import mjson.Json;
import org.sharegov.cirm.utils.GenUtilsMod;

/**
 * File Directory based store for a CirmClusterStatistics.
 * Format 
 * serverName : ""
 * date : "" //isoDateAsString
 * cirmStatistics : { cirmStatistics.toJson}
 * 
 * @author Thomas Hilpold
 */
public class CirmClusterStatisticsStore {
    public static final String SERVER_NAME_PROPERTY = "serverName";
    public static final String DATE_PROPERTY = "date";
    public static final String CIRM_STATS_PROPERTY = "cirmStatistics";
    public static final String FILE_SUFFIX  = ".json";
    private final File storeFolder;
    
    public static CirmClusterStatisticsStore create(File storeFolder) {
        if (!storeFolder.exists()) storeFolder.mkdirs();
        return new CirmClusterStatisticsStore(storeFolder);
    }
    
    public CirmClusterStatisticsStore(File storeFolder) {
        this.storeFolder = storeFolder;
        if (!storeFolder.exists()) throw new IllegalArgumentException("Does not exist, please create: " + storeFolder.getAbsolutePath());
        if (!storeFolder.isDirectory()) throw new IllegalArgumentException();
        if (!storeFolder.canRead()) throw new IllegalArgumentException();
        if (!storeFolder.canWrite()) throw new IllegalArgumentException();
    }
    
    public void readAllInto(CirmClusterStatistics clusterStats) {
        File[] allFiles = storeFolder.listFiles();
        for (int fileIdx = 0; fileIdx < allFiles.length; fileIdx++) {
            File cur = allFiles[fileIdx];
            if (cur.getName().endsWith(FILE_SUFFIX)) {
                try {
                    String fileContent = GenUtilsMod.readTextFile(cur);
                    Json storeJson = Json.read(fileContent);
                    insertSnapshotFromStoreJson(storeJson, clusterStats);
                } catch (Exception e) {
                    System.err.println("Skipped file " + cur.getAbsolutePath() + "  error was " + e.toString() + " msg " + e.getMessage());
                    e.printStackTrace();
                }
            }
        }
    }    
    
    void insertSnapshotFromStoreJson(Json storeJson, CirmClusterStatistics s) {
        String serverName = storeJson.at(SERVER_NAME_PROPERTY).asString();
        String dateStr = storeJson.at(DATE_PROPERTY).asString();
        Date date = GenUtilsMod.parseDate(dateStr);
        Json cirmStatisticsJson = storeJson.at(CIRM_STATS_PROPERTY);
        CirmServerStatistics targetServerDataHistory = s.getDataHistoryByName(serverName);
        if (targetServerDataHistory == null) {
            System.err.println("server denoted in history not configured in CirmClusterStatistics " + serverName + " date " + date.getTime());
        } else {
            CirmStatistics newStats = new CirmStatisticsParser().read(cirmStatisticsJson);
            //overwrites, if already entry at date
            targetServerDataHistory.update(date, newStats);
        }        
    }
    
    /**
     * Writes all snapshots for all servers and the cluster in a CirmClusterStatistics.
     * Does not overwrite existing snapshot files.
     * Order is: Cluster, Server[0], [1], ...
     * @param cs
     * @throws IOException 
     */
    public void writeAllFrom(CirmClusterStatistics cs) throws IOException {
        long start = System.currentTimeMillis();
        writeAllFrom(cs.getClusterDataHistory());
        for (int i = 0; i < cs.getNrOfServers(); i++) {
            writeAllFrom(cs.getServerDataHistory(i));
        }
        System.out.println("Store wrote all in " + (((System.currentTimeMillis() - start)/10)/100.0f) + " seconds");
    }
    
    /**
     * Writes all snapshots for a ServerDataHistory.
     * @param s
     * @throws IOException 
     */
    void writeAllFrom(CirmServerStatistics s) throws IOException {
        String serverName = s.getServerName();
        SortedSet<Date> dates = s.getStatsDates();
        for (Date snapshotDate : dates) {
            writeSnapshot(serverName, snapshotDate, s.getStatsAt(snapshotDate), false);
        }
    }


    /**
     * Writes a single ServerDataHistory snapshot for one server at time date.
     * @param server
     * @param date
     * @param s
     * @param overwrite if a file name matches, normally we don't want to overwrite.
     * @throws IOException 
     */
    void writeSnapshot(String server, Date date, CirmStatistics s, boolean overwrite) throws IOException {
        String fileName = "" + date.getTime() + "-" + server + FILE_SUFFIX;
        File newFile = new File(storeFolder.getAbsolutePath() + File.separatorChar + fileName);
        if (newFile.exists() &&  !overwrite) return;
        Json cirmStatsJson = new CirmStatisticsRenderer().render(s);
        Json fileContentJson = Json.object();
        fileContentJson.set(SERVER_NAME_PROPERTY, server);
        fileContentJson.set(DATE_PROPERTY, GenUtilsMod.formatDate(date));
        fileContentJson.with(cirmStatsJson);
        String fileContent = fileContentJson.toString();
        FileWriter fw = new FileWriter(newFile);
        fw.write(fileContent, 0, fileContent.length());
        fw.close();
    }
}