mmiklavc commented on a change in pull request #1399: METRON-2073: Create in-memory use case for enrichment with map type and flatfile summarizer URL: https://github.com/apache/metron/pull/1399#discussion_r286662099
########## File path: metron-platform/metron-enrichment/metron-enrichment-common/src/main/java/org/apache/metron/enrichment/cache/ObjectCache.java ########## @@ -0,0 +1,118 @@ +/** + * 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(); + protected LoadingCache<String, Object> getCache() { + return cache; + } + + 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)); Review comment: If there's one place to provide an opportunity for dependency injection, I think the `Loader` implementation is it. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
