NIFI-4023, NIFI-4077 This closes #2075. Addressed issue where repository was aging off the wrong index. When it should age off Index 1, it was removing Index 2. As a result, the earliest index is never aged off, and the newest index could potentially be aged off before it is ready to be. Also addressed issue where a query that attempts to read an event that has aged off throws FileNotFoundException (NIFI-4077) instead of skipping over the event. The JavaDocs indicate that the EventIterator should skip records that it cannot find, but SelectiveRecordReaderEventIterator throw FileNotFoundException instead

Signed-off-by: joewitt <joewitt@apache.org>

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/main/java/org/apache/nifi/provenance/index/lucene/IndexDirectoryManager.java

@@ -125,9 +125,9 @@ public class IndexDirectoryManager {
         // If looking at index N, we can determine the index end time by assuming that it is the same as the
         // start time of index N+1. So we determine the time range of each index and select an index only if
         // its start time is before the given timestamp and its end time is <= the given timestamp.
-        for (final List<IndexLocation> startTimeWithFile : startTimeWithFileByStorageDirectory.values()) {
-            for (int i = 0; i < startTimeWithFile.size(); i++) {
-                final IndexLocation indexLoc = startTimeWithFile.get(i);
+        for (final List<IndexLocation> locationList : startTimeWithFileByStorageDirectory.values()) {
+            for (int i = 0; i < locationList.size(); i++) {
+                final IndexLocation indexLoc = locationList.get(i);
 
                 final String partition = indexLoc.getPartitionName();
                 final IndexLocation activeLocation = activeIndices.get(partition);
@@ -143,16 +143,13 @@ public class IndexDirectoryManager {
                     break;
                 }
 
-                if (i < startTimeWithFile.size() - 1) {
-                    final IndexLocation nextLocation = startTimeWithFile.get(i + 1);
-                    final Long indexEndTime = nextLocation.getIndexStartTimestamp();
+                final long indexEndTime = indexLoc.getIndexEndTimestamp();
                 if (indexEndTime <= timestamp) {
                     logger.debug("Considering Index Location {} older than {} ({}) because its events have an EventTime "
-                            + "ranging from {} ({}) to {} ({}) based on the following IndexLocations: {}", nextLocation, timestamp, new Date(timestamp),
-                            indexStartTime, new Date(indexStartTime), indexEndTime, new Date(indexEndTime), startTimeWithFile);
+                        + "ranging from {} ({}) to {} ({}) based on the following IndexLocations: {}", indexLoc, timestamp, new Date(timestamp),
+                        indexStartTime, new Date(indexStartTime), indexEndTime, new Date(indexEndTime), locationList);
 
-                        selected.add(nextLocation.getIndexDirectory());
-                    }
+                    selected.add(indexLoc.getIndexDirectory());
                 }
             }
         }

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/main/java/org/apache/nifi/provenance/index/lucene/IndexLocation.java

@@ -38,6 +38,15 @@ public class IndexLocation {
         return indexStartTimestamp;
     }
 
+    public long getIndexEndTimestamp() {
+        final long lastMod = indexDirectory.lastModified();
+        if (lastMod == 0) {
+            return System.currentTimeMillis();
+        }
+
+        return lastMod;
+    }
+
     public String getPartitionName() {
         return partitionName;
     }

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/main/java/org/apache/nifi/provenance/index/lucene/LuceneEventIndex.java

@@ -648,14 +648,19 @@ public class LuceneEventIndex implements EventIndex {
     void performMaintenance() {
         try {
             final List<ProvenanceEventRecord> firstEvents = eventStore.getEvents(0, 1);
-            if (firstEvents.isEmpty()) {
-                return;
-            }
 
+            final long earliestEventTime;
+            if (firstEvents.isEmpty()) {
+                earliestEventTime = System.currentTimeMillis();
+                logger.debug("Found no events in the Provenance Repository. In order to perform maintenace of the indices, "
+                    + "will assume that the first event time is now ({})", System.currentTimeMillis());
+            } else {
                 final ProvenanceEventRecord firstEvent = firstEvents.get(0);
-            final long earliestEventTime = firstEvent.getEventTime();
+                earliestEventTime = firstEvent.getEventTime();
                 logger.debug("First Event Time is {} ({}) with Event ID {}; will delete any Lucene Index that is older than this",
                     earliestEventTime, new Date(earliestEventTime), firstEvent.getEventId());
+            }
+
             final List<File> indicesBeforeEarliestEvent = directoryManager.getDirectoriesBefore(earliestEventTime);
 
             for (final File index : indicesBeforeEarliestEvent) {

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/main/java/org/apache/nifi/provenance/store/iterator/SelectiveRecordReaderEventIterator.java

@@ -17,7 +17,9 @@
 
 package org.apache.nifi.provenance.store.iterator;
 
+import java.io.EOFException;
 import java.io.File;
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -123,6 +125,7 @@ public class SelectiveRecordReaderEventIterator implements EventIterator {
                     continue;
                 }
 
+                try {
                     // If we determined which file the event should be in, and that's not the file that
                     // we are currently reading from, rotate the reader to the appropriate one.
                     if (!fileForEvent.equals(currentFile)) {
@@ -143,8 +146,9 @@ public class SelectiveRecordReaderEventIterator implements EventIterator {
                         reader.nextRecord();    // consume the event from the stream.
                         return eventOption;
                     }
-
-                continue;
+                } catch (final FileNotFoundException | EOFException e) {
+                    logger.warn("Failed to retrieve Event with ID {}", eventId, e);
+                }
             }
 
             return Optional.empty();

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/test/java/org/apache/nifi/provenance/index/lucene/TestIndexDirectoryManager.java

@@ -129,6 +129,44 @@ public class TestIndexDirectoryManager {
         }
     }
 
+    @Test
+    public void testGetDirectoriesBefore() throws InterruptedException {
+        final RepositoryConfiguration config = createConfig(2);
+        config.setDesiredIndexSize(4096 * 128);
+
+        final File storageDir = config.getStorageDirectories().get("1");
+
+        final File index1 = new File(storageDir, "index-1");
+        final File index2 = new File(storageDir, "index-2");
+
+        final File[] allIndices = new File[] {index1, index2};
+        for (final File file : allIndices) {
+            if (file.exists()) {
+                assertTrue(file.delete());
+            }
+        }
+
+        assertTrue(index1.mkdirs());
+        // Wait 1500 millis because some file systems use only second-precision timestamps instead of millisecond-precision timestamps and
+        // we want to ensure that the two directories have different timestamps. Also using a value of 1500 instead of 1000 because sleep()
+        // can awake before the given time so we give it a buffer zone.
+        Thread.sleep(1500L);
+        final long timestamp = System.currentTimeMillis();
+        assertTrue(index2.mkdirs());
+
+        try {
+            final IndexDirectoryManager mgr = new IndexDirectoryManager(config);
+            mgr.initialize();
+
+            final List<File> dirsBefore = mgr.getDirectoriesBefore(timestamp);
+            assertEquals(1, dirsBefore.size());
+            assertEquals(index1, dirsBefore.get(0));
+        } finally {
+            for (final File file : allIndices) {
+                file.delete();
+            }
+        }
+    }
 
 
     private IndexLocation createLocation(final long timestamp) {

nifi-nar-bundles/nifi-provenance-repository-bundle/nifi-persistent-provenance-repository/src/test/java/org/apache/nifi/provenance/store/iterator/TestSelectiveRecordReaderEventIterator.java

@@ -18,6 +18,7 @@
 package org.apache.nifi.provenance.store.iterator;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
 
 import java.io.File;
 import java.io.IOException;
@@ -25,6 +26,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.Callable;
 import java.util.concurrent.TimeUnit;
@@ -83,6 +85,27 @@ public class TestSelectiveRecordReaderEventIterator {
         assertEquals(Arrays.asList(new File[] {file1, file1000}), filteredFiles);
     }
 
+    @Test
+    public void testFileNotFound() throws IOException {
+        final File file1 = new File("1.prov");
+
+        // Filter out the first file.
+        final List<File> files = new ArrayList<>();
+        files.add(file1);
+
+        List<Long> eventIds = new ArrayList<>();
+        eventIds.add(1L);
+        eventIds.add(5L);
+
+        final RecordReaderFactory readerFactory = (file, logs, maxChars) -> {
+            return RecordReaders.newRecordReader(file, logs, maxChars);
+        };
+
+        final SelectiveRecordReaderEventIterator itr = new SelectiveRecordReaderEventIterator(files, readerFactory, eventIds, 65536);
+        final Optional<ProvenanceEventRecord> firstRecordOption = itr.nextEvent();
+        assertFalse(firstRecordOption.isPresent());
+    }
+
     @Test
     @Ignore("For local testing only. Runs indefinitely")
     public void testPerformanceOfRandomAccessReads() throws Exception {