| /** |
| * 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.metron.enrichment.cache; |
| |
| import com.github.benmanes.caffeine.cache.Caffeine; |
| import com.github.benmanes.caffeine.cache.CacheLoader; |
| import com.github.benmanes.caffeine.cache.LoadingCache; |
| import org.apache.commons.io.IOUtils; |
| import org.apache.commons.lang3.StringUtils; |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.fs.FileSystem; |
| import org.apache.hadoop.fs.Path; |
| import org.apache.metron.common.utils.SerDeUtils; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.io.BufferedInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.lang.invoke.MethodHandles; |
| import java.util.concurrent.locks.ReadWriteLock; |
| import java.util.concurrent.locks.ReentrantReadWriteLock; |
| |
| public class ObjectCache { |
| private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); |
| |
| protected LoadingCache<String, Object> cache; |
| private static ReadWriteLock lock = new ReentrantReadWriteLock(); |
| |
| public class Loader implements CacheLoader<String, Object> { |
| FileSystem fs; |
| ObjectCacheConfig objectCacheConfig; |
| |
| public Loader(Configuration hadoopConfig, ObjectCacheConfig objectCacheConfig) throws IOException { |
| this.fs = FileSystem.get(hadoopConfig); |
| this.objectCacheConfig = objectCacheConfig; |
| } |
| |
| @Override |
| public Object load(String s) throws Exception { |
| LOG.debug("Loading object from path '{}'", s); |
| if (StringUtils.isEmpty(s)) { |
| throw new IllegalArgumentException("Path cannot be empty"); |
| } |
| Object object = null; |
| Path p = new Path(s); |
| if (fs.exists(p)) { |
| if (fs.getFileStatus(p).getLen() <= objectCacheConfig.getMaxFileSize()) { |
| try (InputStream is = new BufferedInputStream(fs.open(p))) { |
| byte[] serialized = IOUtils.toByteArray(is); |
| if (serialized.length > 0) { |
| object = SerDeUtils.fromBytes(serialized, Object.class); |
| } |
| } |
| } else { |
| throw new IllegalArgumentException(String.format("File at path '%s' is larger than the configured max file size of %s", p, objectCacheConfig.getMaxFileSize())); |
| } |
| } else { |
| throw new IllegalArgumentException(String.format("Path '%s' could not be found in HDFS", s)); |
| } |
| return object; |
| } |
| } |
| |
| public Object get(String path) { |
| return cache.get(path); |
| } |
| |
| public void initialize(ObjectCacheConfig config) { |
| try { |
| lock.writeLock().lock(); |
| |
| cache = setupCache(config); |
| } catch (IOException e) { |
| throw new IllegalStateException("Unable to initialize: " + e.getMessage(), e); |
| } finally { |
| lock.writeLock().unlock(); |
| } |
| } |
| |
| public boolean isInitialized() { |
| try { |
| lock.readLock().lock(); |
| return cache != null; |
| } finally { |
| lock.readLock().unlock(); |
| } |
| } |
| |
| protected LoadingCache<String, Object> setupCache(ObjectCacheConfig config) throws IOException { |
| LOG.info("Building ObjectCache with {}", config); |
| return Caffeine.newBuilder().maximumSize(config.getCacheSize()) |
| .expireAfterWrite(config.getCacheExpiration(), config.getTimeUnit()) |
| .removalListener((path, value, removalCause) -> { |
| LOG.debug("Object retrieved from path '{}' was removed with cause {}", path, removalCause); |
| }) |
| .build(new Loader(new Configuration(), config)); |
| } |
| |
| public boolean isEmpty() { |
| return cache == null || cache.estimatedSize() == 0; |
| } |
| |
| public boolean containsKey(String key) { |
| return cache != null && cache.asMap().containsKey(key); |
| } |
| } |