| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.apache.lucene.replicator.nrt; |
| |
| import java.io.FileNotFoundException; |
| import java.io.IOException; |
| import java.nio.file.NoSuchFileException; |
| import java.util.Collection; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import org.apache.lucene.index.IndexFileNames; |
| import org.apache.lucene.store.Directory; |
| import org.apache.lucene.store.IOContext; |
| |
| // TODO: can we factor/share with IFD: this is doing exactly the same thing, but on the replica side |
| |
| class ReplicaFileDeleter { |
| private final Map<String,Integer> refCounts = new HashMap<String,Integer>(); |
| private final Directory dir; |
| private final Node node; |
| |
| public ReplicaFileDeleter(Node node, Directory dir) throws IOException { |
| this.dir = dir; |
| this.node = node; |
| } |
| |
| /** Used only by asserts: returns true if the file exists |
| * (can be opened), false if it cannot be opened, and |
| * (unlike Java's File.exists) throws IOException if |
| * there's some unexpected error. */ |
| private static boolean slowFileExists(Directory dir, String fileName) throws IOException { |
| try { |
| dir.openInput(fileName, IOContext.DEFAULT).close(); |
| return true; |
| } catch (NoSuchFileException | FileNotFoundException e) { |
| return false; |
| } |
| } |
| |
| public synchronized void incRef(Collection<String> fileNames) throws IOException { |
| for(String fileName : fileNames) { |
| |
| assert slowFileExists(dir, fileName): "file " + fileName + " does not exist!"; |
| |
| Integer curCount = refCounts.get(fileName); |
| if (curCount == null) { |
| refCounts.put(fileName, 1); |
| } else { |
| refCounts.put(fileName, curCount.intValue() + 1); |
| } |
| } |
| } |
| |
| public synchronized void decRef(Collection<String> fileNames) throws IOException { |
| Set<String> toDelete = new HashSet<>(); |
| for(String fileName : fileNames) { |
| Integer curCount = refCounts.get(fileName); |
| assert curCount != null: "fileName=" + fileName; |
| assert curCount.intValue() > 0; |
| if (curCount.intValue() == 1) { |
| refCounts.remove(fileName); |
| toDelete.add(fileName); |
| } else { |
| refCounts.put(fileName, curCount.intValue() - 1); |
| } |
| } |
| |
| delete(toDelete); |
| |
| // TODO: this local IR could incRef files here, like we do now with IW's NRT readers ... then we can assert this again: |
| |
| // we can't assert this, e.g a search can be running when we switch to a new NRT point, holding a previous IndexReader still open for |
| // a bit: |
| /* |
| // We should never attempt deletion of a still-open file: |
| Set<String> delOpen = ((MockDirectoryWrapper) dir).getOpenDeletedFiles(); |
| if (delOpen.isEmpty() == false) { |
| node.message("fail: we tried to delete these still-open files: " + delOpen); |
| throw new AssertionError("we tried to delete these still-open files: " + delOpen); |
| } |
| */ |
| } |
| |
| private synchronized void delete(Collection<String> toDelete) throws IOException { |
| if (Node.VERBOSE_FILES) { |
| node.message("now delete " + toDelete.size() + " files: " + toDelete); |
| } |
| |
| // First pass: delete any segments_N files. We do these first to be certain stale commit points are removed |
| // before we remove any files they reference, in case we crash right now: |
| for (String fileName : toDelete) { |
| assert refCounts.containsKey(fileName) == false; |
| if (fileName.startsWith(IndexFileNames.SEGMENTS)) { |
| delete(fileName); |
| } |
| } |
| |
| // Only delete other files if we were able to remove the segments_N files; this way we never |
| // leave a corrupt commit in the index even in the presense of virus checkers: |
| for(String fileName : toDelete) { |
| assert refCounts.containsKey(fileName) == false; |
| if (fileName.startsWith(IndexFileNames.SEGMENTS) == false) { |
| delete(fileName); |
| } |
| } |
| |
| } |
| |
| private synchronized void delete(String fileName) throws IOException { |
| if (Node.VERBOSE_FILES) { |
| node.message("file " + fileName + ": now delete"); |
| } |
| dir.deleteFile(fileName); |
| } |
| |
| public synchronized Integer getRefCount(String fileName) { |
| return refCounts.get(fileName); |
| } |
| |
| public synchronized void deleteIfNoRef(String fileName) throws IOException { |
| if (refCounts.containsKey(fileName) == false) { |
| deleteNewFile(fileName); |
| } |
| } |
| |
| public synchronized void deleteNewFile(String fileName) throws IOException { |
| delete(fileName); |
| } |
| |
| /* |
| public synchronized Set<String> getPending() { |
| return new HashSet<String>(pending); |
| } |
| */ |
| |
| public synchronized void deleteUnknownFiles(String segmentsFileName) throws IOException { |
| Set<String> toDelete = new HashSet<>(); |
| for(String fileName : dir.listAll()) { |
| if (refCounts.containsKey(fileName) == false && |
| fileName.equals("write.lock") == false && |
| fileName.equals(segmentsFileName) == false) { |
| node.message("will delete unknown file \"" + fileName + "\""); |
| toDelete.add(fileName); |
| } |
| } |
| |
| delete(toDelete); |
| } |
| } |