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1 /**
2  * Copyright (c) 2010-2023 Contributors to the openHAB project
3  *
4  * See the NOTICE file(s) distributed with this work for additional
5  * information.
6  *
7  * This program and the accompanying materials are made available under the
8  * terms of the Eclipse Public License 2.0 which is available at
9  * http://www.eclipse.org/legal/epl-2.0
10  *
11  * SPDX-License-Identifier: EPL-2.0
12  */
13 package org.openhab.persistence.rrd4j.internal;
14
15 import java.io.IOException;
16 import java.nio.file.Files;
17 import java.nio.file.Path;
18 import java.time.Instant;
19 import java.time.ZoneId;
20 import java.time.ZonedDateTime;
21 import java.util.ArrayList;
22 import java.util.Collections;
23 import java.util.Iterator;
24 import java.util.List;
25 import java.util.Locale;
26 import java.util.Map;
27 import java.util.Set;
28 import java.util.concurrent.ConcurrentHashMap;
29 import java.util.concurrent.ConcurrentSkipListMap;
30 import java.util.concurrent.Executors;
31 import java.util.concurrent.RejectedExecutionException;
32 import java.util.concurrent.ScheduledExecutorService;
33 import java.util.concurrent.ScheduledFuture;
34 import java.util.concurrent.TimeUnit;
35 import java.util.stream.Collectors;
36 import java.util.stream.Stream;
37
38 import javax.measure.Quantity;
39 import javax.measure.Unit;
40
41 import org.eclipse.jdt.annotation.NonNullByDefault;
42 import org.eclipse.jdt.annotation.Nullable;
43 import org.openhab.core.OpenHAB;
44 import org.openhab.core.common.NamedThreadFactory;
45 import org.openhab.core.items.GroupItem;
46 import org.openhab.core.items.Item;
47 import org.openhab.core.items.ItemNotFoundException;
48 import org.openhab.core.items.ItemRegistry;
49 import org.openhab.core.items.ItemUtil;
50 import org.openhab.core.library.CoreItemFactory;
51 import org.openhab.core.library.items.ColorItem;
52 import org.openhab.core.library.items.ContactItem;
53 import org.openhab.core.library.items.DimmerItem;
54 import org.openhab.core.library.items.NumberItem;
55 import org.openhab.core.library.items.RollershutterItem;
56 import org.openhab.core.library.items.SwitchItem;
57 import org.openhab.core.library.types.DecimalType;
58 import org.openhab.core.library.types.OnOffType;
59 import org.openhab.core.library.types.OpenClosedType;
60 import org.openhab.core.library.types.PercentType;
61 import org.openhab.core.library.types.QuantityType;
62 import org.openhab.core.persistence.FilterCriteria;
63 import org.openhab.core.persistence.FilterCriteria.Ordering;
64 import org.openhab.core.persistence.HistoricItem;
65 import org.openhab.core.persistence.PersistenceItemInfo;
66 import org.openhab.core.persistence.PersistenceService;
67 import org.openhab.core.persistence.QueryablePersistenceService;
68 import org.openhab.core.persistence.strategy.PersistenceCronStrategy;
69 import org.openhab.core.persistence.strategy.PersistenceStrategy;
70 import org.openhab.core.types.State;
71 import org.osgi.service.component.annotations.Activate;
72 import org.osgi.service.component.annotations.Component;
73 import org.osgi.service.component.annotations.ConfigurationPolicy;
74 import org.osgi.service.component.annotations.Deactivate;
75 import org.osgi.service.component.annotations.Modified;
76 import org.osgi.service.component.annotations.Reference;
77 import org.rrd4j.ConsolFun;
78 import org.rrd4j.DsType;
79 import org.rrd4j.core.FetchData;
80 import org.rrd4j.core.FetchRequest;
81 import org.rrd4j.core.RrdDb;
82 import org.rrd4j.core.RrdDb.Builder;
83 import org.rrd4j.core.RrdDbPool;
84 import org.rrd4j.core.RrdDef;
85 import org.rrd4j.core.Sample;
86 import org.slf4j.Logger;
87 import org.slf4j.LoggerFactory;
88
89 /**
90  * This is the implementation of the RRD4j {@link PersistenceService}. To learn
91  * more about RRD4j please visit their
92  * <a href="https://github.com/rrd4j/rrd4j">website</a>.
93  *
94  * @author Kai Kreuzer - Initial contribution
95  * @author Jan N. Klug - some improvements
96  * @author Karel Goderis - remove TimerThread dependency
97  */
98 @NonNullByDefault
99 @Component(service = { PersistenceService.class,
100         QueryablePersistenceService.class }, configurationPid = "org.openhab.rrd4j", configurationPolicy = ConfigurationPolicy.OPTIONAL)
101 public class RRD4jPersistenceService implements QueryablePersistenceService {
102
103     public static final String SERVICE_ID = "rrd4j";
104
105     private static final String DEFAULT_OTHER = "default_other";
106     private static final String DEFAULT_NUMERIC = "default_numeric";
107     private static final String DEFAULT_QUANTIFIABLE = "default_quantifiable";
108
109     private static final Set<String> SUPPORTED_TYPES = Set.of(CoreItemFactory.SWITCH, CoreItemFactory.CONTACT,
110             CoreItemFactory.DIMMER, CoreItemFactory.NUMBER, CoreItemFactory.ROLLERSHUTTER, CoreItemFactory.COLOR);
111
112     private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1,
113             new NamedThreadFactory("RRD4j"));
114
115     private final Map<String, RrdDefConfig> rrdDefs = new ConcurrentHashMap<>();
116
117     private final ConcurrentSkipListMap<Long, Map<String, Double>> storageMap = new ConcurrentSkipListMap<>();
118
119     private static final String DATASOURCE_STATE = "state";
120
121     private static final Path DB_FOLDER = Path.of(OpenHAB.getUserDataFolder(), "persistence", "rrd4j").toAbsolutePath();
122
123     private static final RrdDbPool DATABASE_POOL = new RrdDbPool();
124
125     private final Logger logger = LoggerFactory.getLogger(RRD4jPersistenceService.class);
126     private final ItemRegistry itemRegistry;
127     private boolean active = false;
128
129     public static Path getDatabasePath(String name) {
130         return DB_FOLDER.resolve(name + ".rrd");
131     }
132
133     public static RrdDbPool getDatabasePool() {
134         return DATABASE_POOL;
135     }
136
137     private final ScheduledFuture<?> storeJob;
138
139     @Activate
140     public RRD4jPersistenceService(final @Reference ItemRegistry itemRegistry, Map<String, Object> config) {
141         this.itemRegistry = itemRegistry;
142         storeJob = scheduler.scheduleWithFixedDelay(() -> doStore(false), 1, 1, TimeUnit.SECONDS);
143         modified(config);
144         active = true;
145     }
146
147     @Modified
148     protected void modified(final Map<String, Object> config) {
149         // clean existing definitions
150         rrdDefs.clear();
151
152         // add default configurations
153
154         RrdDefConfig defaultNumeric = new RrdDefConfig(DEFAULT_NUMERIC);
155         // use 10 seconds as a step size for numeric values and allow a 10 minute silence between updates
156         defaultNumeric.setDef("GAUGE,600,U,U,10");
157         // define 5 different boxes:
158         // 1. granularity of 10s for the last hour
159         // 2. granularity of 1m for the last week
160         // 3. granularity of 15m for the last year
161         // 4. granularity of 1h for the last 5 years
162         // 5. granularity of 1d for the last 10 years
163         defaultNumeric
164                 .addArchives("LAST,0.5,1,360:LAST,0.5,6,10080:LAST,0.5,90,36500:LAST,0.5,360,43800:LAST,0.5,8640,3650");
165         rrdDefs.put(DEFAULT_NUMERIC, defaultNumeric);
166
167         RrdDefConfig defaultQuantifiable = new RrdDefConfig(DEFAULT_QUANTIFIABLE);
168         // use 10 seconds as a step size for numeric values and allow a 10 minute silence between updates
169         defaultQuantifiable.setDef("GAUGE,600,U,U,10");
170         // define 5 different boxes:
171         // 1. granularity of 10s for the last hour
172         // 2. granularity of 1m for the last week
173         // 3. granularity of 15m for the last year
174         // 4. granularity of 1h for the last 5 years
175         // 5. granularity of 1d for the last 10 years
176         defaultQuantifiable.addArchives(
177                 "AVERAGE,0.5,1,360:AVERAGE,0.5,6,10080:AVERAGE,0.5,90,36500:AVERAGE,0.5,360,43800:AVERAGE,0.5,8640,3650");
178         rrdDefs.put(DEFAULT_QUANTIFIABLE, defaultQuantifiable);
179
180         RrdDefConfig defaultOther = new RrdDefConfig(DEFAULT_OTHER);
181         // use 5 seconds as a step size for discrete values and allow a 1h silence between updates
182         defaultOther.setDef("GAUGE,3600,U,U,5");
183         // define 4 different boxes:
184         // 1. granularity of 5s for the last hour
185         // 2. granularity of 1m for the last week
186         // 3. granularity of 15m for the last year
187         // 4. granularity of 4h for the last 10 years
188         defaultOther.addArchives("LAST,0.5,1,720:LAST,0.5,12,10080:LAST,0.5,180,35040:LAST,0.5,2880,21900");
189         rrdDefs.put(DEFAULT_OTHER, defaultOther);
190
191         if (config.isEmpty()) {
192             logger.debug("using default configuration only");
193             return;
194         }
195
196         Iterator<String> keys = config.keySet().iterator();
197         while (keys.hasNext()) {
198             String key = keys.next();
199
200             if ("service.pid".equals(key) || "component.name".equals(key)) {
201                 // ignore service.pid and name
202                 continue;
203             }
204
205             String[] subkeys = key.split("\\.");
206             if (subkeys.length != 2) {
207                 logger.debug("config '{}' should have the format 'name.configkey'", key);
208                 continue;
209             }
210
211             Object v = config.get(key);
212             if (v instanceof String) {
213                 String value = (String) v;
214                 String name = subkeys[0].toLowerCase();
215                 String property = subkeys[1].toLowerCase();
216
217                 if (value.isBlank()) {
218                     logger.trace("Config is empty: {}", property);
219                     continue;
220                 } else {
221                     logger.trace("Processing config: {} = {}", property, value);
222                 }
223
224                 RrdDefConfig rrdDef = rrdDefs.get(name);
225                 if (rrdDef == null) {
226                     rrdDef = new RrdDefConfig(name);
227                     rrdDefs.put(name, rrdDef);
228                 }
229
230                 try {
231                     if ("def".equals(property)) {
232                         rrdDef.setDef(value);
233                     } else if ("archives".equals(property)) {
234                         rrdDef.addArchives(value);
235                     } else if ("items".equals(property)) {
236                         rrdDef.addItems(value);
237                     } else {
238                         logger.debug("Unknown property {} : {}", property, value);
239                     }
240                 } catch (IllegalArgumentException e) {
241                     logger.warn("Ignoring illegal configuration: {}", e.getMessage());
242                 }
243             }
244         }
245
246         for (RrdDefConfig rrdDef : rrdDefs.values()) {
247             if (rrdDef.isValid()) {
248                 logger.debug("Created {}", rrdDef);
249             } else {
250                 logger.info("Removing invalid definition {}", rrdDef);
251                 rrdDefs.remove(rrdDef.name);
252             }
253         }
254     }
255
256     @Deactivate
257     protected void deactivate() {
258         active = false;
259         storeJob.cancel(false);
260
261         // make sure we really store everything
262         doStore(true);
263     }
264
265     @Override
266     public String getId() {
267         return SERVICE_ID;
268     }
269
270     @Override
271     public String getLabel(@Nullable Locale locale) {
272         return "RRD4j";
273     }
274
275     @Override
276     public void store(final Item item, @Nullable final String alias) {
277         if (!active) {
278             logger.warn("Tried to store {} but service is not yet ready (or shutting down).", item);
279             return;
280         }
281
282         if (!isSupportedItemType(item)) {
283             logger.trace("Ignoring item '{}' since its type {} is not supported", item.getName(), item.getType());
284             return;
285         }
286         final String name = alias == null ? item.getName() : alias;
287
288         Double value;
289
290         if (item instanceof NumberItem nItem && item.getState() instanceof QuantityType<?> qState) {
291             Unit<? extends Quantity<?>> unit = nItem.getUnit();
292             if (unit != null) {
293                 QuantityType<?> convertedState = qState.toUnit(unit);
294                 if (convertedState != null) {
295                     value = convertedState.doubleValue();
296                 } else {
297                     value = null;
298                     logger.warn(
299                             "Failed to convert state '{}' to unit '{}'. Please check your item definition for correctness.",
300                             qState, unit);
301                 }
302             } else {
303                 value = qState.doubleValue();
304             }
305         } else {
306             DecimalType state = item.getStateAs(DecimalType.class);
307             if (state != null) {
308                 value = state.toBigDecimal().doubleValue();
309             } else {
310                 value = null;
311             }
312         }
313
314         if (value == null) {
315             // we could not convert the value
316             return;
317         }
318
319         long now = System.currentTimeMillis() / 1000;
320         Double oldValue = storageMap.computeIfAbsent(now, t -> new ConcurrentHashMap<>()).put(name, value);
321         if (oldValue != null && !oldValue.equals(value)) {
322             logger.debug(
323                     "Discarding value {} for item {} with timestamp {} because a new value ({}) arrived with the same timestamp.",
324                     oldValue, name, now, value);
325         }
326     }
327
328     private void doStore(boolean force) {
329         while (!storageMap.isEmpty()) {
330             long timestamp = storageMap.firstKey();
331             long now = System.currentTimeMillis() / 1000;
332             if (now > timestamp || force) {
333                 // no new elements can be added for this timestamp because we are already past that time or the service
334                 // requires forced storing
335                 Map<String, Double> values = storageMap.pollFirstEntry().getValue();
336                 values.forEach((name, value) -> writePointToDatabase(name, value, timestamp));
337             } else {
338                 return;
339             }
340         }
341     }
342
343     private synchronized void writePointToDatabase(String name, double value, long timestamp) {
344         RrdDb db = null;
345         try {
346             db = getDB(name, true);
347         } catch (Exception e) {
348             logger.warn("Failed to open rrd4j database '{}' to store data ({})", name, e.toString());
349         }
350         if (db == null) {
351             return;
352         }
353
354         ConsolFun function = getConsolidationFunction(db);
355         if (function != ConsolFun.AVERAGE) {
356             try {
357                 // we store the last value again, so that the value change
358                 // in the database is not interpolated, but
359                 // happens right at this spot
360                 if (timestamp - 1 > db.getLastUpdateTime()) {
361                     // only do it if there is not already a value
362                     double lastValue = db.getLastDatasourceValue(DATASOURCE_STATE);
363                     if (!Double.isNaN(lastValue)) {
364                         Sample sample = db.createSample();
365                         sample.setTime(timestamp - 1);
366                         sample.setValue(DATASOURCE_STATE, lastValue);
367                         sample.update();
368                         logger.debug("Stored '{}' as value '{}' with timestamp {} in rrd4j database (again)", name,
369                                 lastValue, timestamp - 1);
370                     }
371                 }
372             } catch (IOException e) {
373                 logger.debug("Error storing last value (again) for {}: {}", e.getMessage(), name);
374             }
375         }
376         try {
377             Sample sample = db.createSample();
378             sample.setTime(timestamp);
379             double storeValue = value;
380             if (db.getDatasource(DATASOURCE_STATE).getType() == DsType.COUNTER) {
381                 // counter values must be adjusted by stepsize
382                 storeValue = value * db.getRrdDef().getStep();
383             }
384             sample.setValue(DATASOURCE_STATE, storeValue);
385             sample.update();
386             logger.debug("Stored '{}' as value '{}' with timestamp {} in rrd4j database", name, storeValue, timestamp);
387         } catch (Exception e) {
388             logger.warn("Could not persist '{}' to rrd4j database: {}", name, e.getMessage());
389         }
390         try {
391             db.close();
392         } catch (IOException e) {
393             logger.debug("Error closing rrd4j database: {}", e.getMessage());
394         }
395     }
396
397     @Override
398     public void store(Item item) {
399         store(item, null);
400     }
401
402     @Override
403     public Iterable<HistoricItem> query(FilterCriteria filter) {
404         ZonedDateTime filterBeginDate = filter.getBeginDate();
405         ZonedDateTime filterEndDate = filter.getEndDate();
406         if (filterBeginDate != null && filterEndDate != null && filterBeginDate.isAfter(filterEndDate)) {
407             throw new IllegalArgumentException("begin (" + filterBeginDate + ") before end (" + filterEndDate + ")");
408         }
409
410         String itemName = filter.getItemName();
411         if (itemName == null) {
412             logger.warn("Item name is missing in filter {}", filter);
413             return List.of();
414         }
415         logger.trace("Querying rrd4j database for item '{}'", itemName);
416
417         RrdDb db = null;
418         try {
419             db = getDB(itemName, false);
420         } catch (Exception e) {
421             logger.warn("Failed to open rrd4j database '{}' for querying ({})", itemName, e.toString());
422             return List.of();
423         }
424         if (db == null) {
425             logger.debug("Could not find item '{}' in rrd4j database", itemName);
426             return List.of();
427         }
428
429         Item item = null;
430         Unit<?> unit = null;
431         try {
432             item = itemRegistry.getItem(itemName);
433             if (item instanceof NumberItem) {
434                 // we already retrieve the unit here once as it is a very costly operation,
435                 // see https://github.com/openhab/openhab-addons/issues/8928
436                 unit = ((NumberItem) item).getUnit();
437             }
438         } catch (ItemNotFoundException e) {
439             logger.debug("Could not find item '{}' in registry", itemName);
440         }
441
442         long start = 0L;
443         long end = filterEndDate == null ? System.currentTimeMillis() / 1000
444                 : filterEndDate.toInstant().getEpochSecond();
445
446         try {
447             if (filterBeginDate == null) {
448                 // as rrd goes back for years and gets more and more
449                 // inaccurate, we only support descending order
450                 // and a single return value
451                 // if there is no begin date is given - this case is
452                 // required specifically for the historicState()
453                 // query, which we want to support
454                 if (filter.getOrdering() == Ordering.DESCENDING && filter.getPageSize() == 1
455                         && filter.getPageNumber() == 0) {
456                     if (filterEndDate == null) {
457                         // we are asked only for the most recent value!
458                         double lastValue = db.getLastDatasourceValue(DATASOURCE_STATE);
459                         if (!Double.isNaN(lastValue)) {
460                             HistoricItem rrd4jItem = new RRD4jItem(itemName, mapToState(lastValue, item, unit),
461                                     ZonedDateTime.ofInstant(Instant.ofEpochMilli(db.getLastArchiveUpdateTime() * 1000),
462                                             ZoneId.systemDefault()));
463                             return List.of(rrd4jItem);
464                         } else {
465                             return List.of();
466                         }
467                     } else {
468                         start = end;
469                     }
470                 } else {
471                     throw new UnsupportedOperationException(
472                             "rrd4j does not allow querys without a begin date, unless order is descending and a single value is requested");
473                 }
474             } else {
475                 start = filterBeginDate.toInstant().getEpochSecond();
476             }
477
478             // do not call method {@link RrdDb#createFetchRequest(ConsolFun, long, long, long)} if start > end to avoid
479             // an IAE to be thrown
480             if (start > end) {
481                 logger.debug("Could not query rrd4j database for item '{}': start ({}) > end ({})", itemName, start,
482                         end);
483                 return List.of();
484             }
485
486             FetchRequest request = db.createFetchRequest(getConsolidationFunction(db), start, end, 1);
487             FetchData result = request.fetchData();
488
489             List<HistoricItem> items = new ArrayList<>();
490             long ts = result.getFirstTimestamp();
491             long step = result.getRowCount() > 1 ? result.getStep() : 0;
492             for (double value : result.getValues(DATASOURCE_STATE)) {
493                 if (!Double.isNaN(value) && (((ts >= start) && (ts <= end)) || (start == end))) {
494                     RRD4jItem rrd4jItem = new RRD4jItem(itemName, mapToState(value, item, unit),
495                             ZonedDateTime.ofInstant(Instant.ofEpochSecond(ts), ZoneId.systemDefault()));
496                     items.add(rrd4jItem);
497                 }
498                 ts += step;
499             }
500             return items;
501         } catch (IOException e) {
502             logger.warn("Could not query rrd4j database for item '{}': {}", itemName, e.getMessage());
503             return List.of();
504         } finally {
505             try {
506                 db.close();
507             } catch (IOException e) {
508                 logger.debug("Error closing rrd4j database: {}", e.getMessage());
509             }
510         }
511     }
512
513     @Override
514     public Set<PersistenceItemInfo> getItemInfo() {
515         return Set.of();
516     }
517
518     protected synchronized @Nullable RrdDb getDB(String alias, boolean createFileIfAbsent) {
519         RrdDb db = null;
520         Path path = getDatabasePath(alias);
521         try {
522             Builder builder = RrdDb.getBuilder();
523             builder.setPool(DATABASE_POOL);
524
525             if (Files.exists(path)) {
526                 // recreate the RrdDb instance from the file
527                 builder.setPath(path.toString());
528                 db = builder.build();
529             } else if (createFileIfAbsent) {
530                 if (!Files.exists(DB_FOLDER)) {
531                     Files.createDirectories(DB_FOLDER);
532                 }
533                 RrdDef rrdDef = getRrdDef(alias, path);
534                 if (rrdDef != null) {
535                     // create a new database file
536                     builder.setRrdDef(rrdDef);
537                     db = builder.build();
538                 } else {
539                     logger.debug(
540                             "Did not create rrd4j database for item '{}' since no rrd definition could be determined. This is likely due to an unsupported item type.",
541                             alias);
542                 }
543             }
544         } catch (IOException e) {
545             logger.error("Could not create rrd4j database file '{}': {}", path, e.getMessage());
546         } catch (RejectedExecutionException e) {
547             // this happens if the system is shut down
548             logger.debug("Could not create rrd4j database file '{}': {}", path, e.getMessage());
549         }
550         return db;
551     }
552
553     private @Nullable RrdDefConfig getRrdDefConfig(String itemName) {
554         RrdDefConfig useRdc = null;
555         for (Map.Entry<String, RrdDefConfig> e : rrdDefs.entrySet()) {
556             // try to find special config
557             RrdDefConfig rdc = e.getValue();
558             if (rdc.appliesTo(itemName)) {
559                 useRdc = rdc;
560                 break;
561             }
562         }
563         if (useRdc == null) { // not defined, use defaults
564             try {
565                 Item item = itemRegistry.getItem(itemName);
566                 if (!isSupportedItemType(item)) {
567                     return null;
568                 }
569                 if (item instanceof NumberItem) {
570                     NumberItem numberItem = (NumberItem) item;
571                     useRdc = numberItem.getDimension() != null ? rrdDefs.get(DEFAULT_QUANTIFIABLE)
572                             : rrdDefs.get(DEFAULT_NUMERIC);
573                 } else {
574                     useRdc = rrdDefs.get(DEFAULT_OTHER);
575                 }
576             } catch (ItemNotFoundException e) {
577                 logger.debug("Could not find item '{}' in registry", itemName);
578                 return null;
579             }
580         }
581         logger.trace("Using rrd definition '{}' for item '{}'.", useRdc, itemName);
582         return useRdc;
583     }
584
585     private @Nullable RrdDef getRrdDef(String itemName, Path path) {
586         RrdDef rrdDef = new RrdDef(path.toString());
587         RrdDefConfig useRdc = getRrdDefConfig(itemName);
588         if (useRdc != null) {
589             rrdDef.setStep(useRdc.step);
590             rrdDef.setStartTime(System.currentTimeMillis() / 1000 - useRdc.step);
591             rrdDef.addDatasource(DATASOURCE_STATE, useRdc.dsType, useRdc.heartbeat, useRdc.min, useRdc.max);
592             for (RrdArchiveDef rad : useRdc.archives) {
593                 rrdDef.addArchive(rad.fcn, rad.xff, rad.steps, rad.rows);
594             }
595             return rrdDef;
596         } else {
597             return null;
598         }
599     }
600
601     public ConsolFun getConsolidationFunction(RrdDb db) {
602         try {
603             return db.getRrdDef().getArcDefs()[0].getConsolFun();
604         } catch (IOException e) {
605             return ConsolFun.MAX;
606         }
607     }
608
609     @SuppressWarnings({ "unchecked", "rawtypes" })
610     private State mapToState(double value, @Nullable Item item, @Nullable Unit unit) {
611         if (item instanceof GroupItem) {
612             item = ((GroupItem) item).getBaseItem();
613         }
614
615         if (item instanceof SwitchItem && !(item instanceof DimmerItem)) {
616             return value == 0.0d ? OnOffType.OFF : OnOffType.ON;
617         } else if (item instanceof ContactItem) {
618             return value == 0.0d ? OpenClosedType.CLOSED : OpenClosedType.OPEN;
619         } else if (item instanceof DimmerItem || item instanceof RollershutterItem || item instanceof ColorItem) {
620             // make sure Items that need PercentTypes instead of DecimalTypes do receive the right information
621             return new PercentType((int) Math.round(value * 100));
622         } else if (item instanceof NumberItem) {
623             if (unit != null) {
624                 return new QuantityType(value, unit);
625             }
626         }
627         return new DecimalType(value);
628     }
629
630     private boolean isSupportedItemType(Item item) {
631         if (item instanceof GroupItem) {
632             final Item baseItem = ((GroupItem) item).getBaseItem();
633             if (baseItem != null) {
634                 item = baseItem;
635             }
636         }
637
638         return SUPPORTED_TYPES.contains(ItemUtil.getMainItemType(item.getType()));
639     }
640
641     public List<String> getRrdFiles() {
642         try (Stream<Path> stream = Files.list(DB_FOLDER)) {
643             return stream.filter(file -> !Files.isDirectory(file) && file.toFile().getName().endsWith(".rrd"))
644                     .map(file -> file.toFile().getName()).collect(Collectors.toList());
645         } catch (IOException e) {
646             return List.of();
647         }
648     }
649
650     private static class RrdArchiveDef {
651         public @Nullable ConsolFun fcn;
652         public double xff;
653         public int steps, rows;
654
655         @Override
656         public String toString() {
657             StringBuilder sb = new StringBuilder(" " + fcn);
658             sb.append(" xff = ").append(xff);
659             sb.append(" steps = ").append(steps);
660             sb.append(" rows = ").append(rows);
661             return sb.toString();
662         }
663     }
664
665     private class RrdDefConfig {
666         public String name;
667         public @Nullable DsType dsType;
668         public int heartbeat, step;
669         public double min, max;
670         public List<RrdArchiveDef> archives;
671         public List<String> itemNames;
672
673         private boolean isInitialized;
674
675         public RrdDefConfig(String name) {
676             this.name = name;
677             archives = new ArrayList<>();
678             itemNames = new ArrayList<>();
679             isInitialized = false;
680         }
681
682         public void setDef(String defString) {
683             String[] opts = defString.split(",");
684             if (opts.length != 5) { // check if correct number of parameters
685                 logger.warn("invalid number of parameters {}: {}", name, defString);
686                 return;
687             }
688
689             if ("ABSOLUTE".equals(opts[0])) { // dsType
690                 dsType = DsType.ABSOLUTE;
691             } else if ("COUNTER".equals(opts[0])) {
692                 dsType = DsType.COUNTER;
693             } else if ("DERIVE".equals(opts[0])) {
694                 dsType = DsType.DERIVE;
695             } else if ("GAUGE".equals(opts[0])) {
696                 dsType = DsType.GAUGE;
697             } else {
698                 logger.warn("{}: dsType {} not supported", name, opts[0]);
699             }
700
701             heartbeat = Integer.parseInt(opts[1]);
702
703             if ("U".equals(opts[2])) {
704                 min = Double.NaN;
705             } else {
706                 min = Double.parseDouble(opts[2]);
707             }
708
709             if ("U".equals(opts[3])) {
710                 max = Double.NaN;
711             } else {
712                 max = Double.parseDouble(opts[3]);
713             }
714
715             step = Integer.parseInt(opts[4]);
716
717             isInitialized = true; // successfully initialized
718
719             return;
720         }
721
722         public void addArchives(String archivesString) {
723             String splitArchives[] = archivesString.split(":");
724             for (String archiveString : splitArchives) {
725                 String[] opts = archiveString.split(",");
726                 if (opts.length != 4) { // check if correct number of parameters
727                     logger.warn("invalid number of parameters {}: {}", name, archiveString);
728                     return;
729                 }
730                 RrdArchiveDef arc = new RrdArchiveDef();
731
732                 if ("AVERAGE".equals(opts[0])) {
733                     arc.fcn = ConsolFun.AVERAGE;
734                 } else if ("MIN".equals(opts[0])) {
735                     arc.fcn = ConsolFun.MIN;
736                 } else if ("MAX".equals(opts[0])) {
737                     arc.fcn = ConsolFun.MAX;
738                 } else if ("LAST".equals(opts[0])) {
739                     arc.fcn = ConsolFun.LAST;
740                 } else if ("FIRST".equals(opts[0])) {
741                     arc.fcn = ConsolFun.FIRST;
742                 } else if ("TOTAL".equals(opts[0])) {
743                     arc.fcn = ConsolFun.TOTAL;
744                 } else {
745                     logger.warn("{}: consolidation function  {} not supported", name, opts[0]);
746                 }
747                 arc.xff = Double.parseDouble(opts[1]);
748                 arc.steps = Integer.parseInt(opts[2]);
749                 arc.rows = Integer.parseInt(opts[3]);
750                 archives.add(arc);
751             }
752         }
753
754         public void addItems(String itemsString) {
755             Collections.addAll(itemNames, itemsString.split(","));
756         }
757
758         public boolean appliesTo(String item) {
759             return itemNames.contains(item);
760         }
761
762         public boolean isValid() { // a valid configuration must be initialized
763             // and contain at least one function
764             return isInitialized && !archives.isEmpty();
765         }
766
767         @Override
768         public String toString() {
769             StringBuilder sb = new StringBuilder(name);
770             sb.append(" = ").append(dsType);
771             sb.append(" heartbeat = ").append(heartbeat);
772             sb.append(" min/max = ").append(min).append("/").append(max);
773             sb.append(" step = ").append(step);
774             sb.append(" ").append(archives.size()).append(" archives(s) = [");
775             for (RrdArchiveDef arc : archives) {
776                 sb.append(arc.toString());
777             }
778             sb.append("] ");
779             sb.append(itemNames.size()).append(" items(s) = [");
780             for (String item : itemNames) {
781                 sb.append(item).append(" ");
782             }
783             sb.append("]");
784             return sb.toString();
785         }
786     }
787
788     @Override
789     public List<PersistenceStrategy> getDefaultStrategies() {
790         return List.of(PersistenceStrategy.Globals.RESTORE, PersistenceStrategy.Globals.CHANGE,
791                 new PersistenceCronStrategy("everyMinute", "0 * * * * ?"));
792     }
793 }