| /** |
| * 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.stellar; |
| |
| import org.apache.metron.enrichment.cache.ObjectCache; |
| import org.apache.metron.enrichment.cache.ObjectCacheConfig; |
| import org.apache.metron.stellar.dsl.Context; |
| import org.apache.metron.stellar.dsl.ParseException; |
| import org.apache.metron.stellar.dsl.Stellar; |
| import org.apache.metron.stellar.dsl.StellarFunction; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import java.lang.invoke.MethodHandles; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| |
| @Stellar(namespace="OBJECT" |
| ,name="GET" |
| ,description="Retrieve and deserialize a serialized object from HDFS. " + |
| "The cache can be specified via three properties in the global config: " + |
| "\"" + ObjectCacheConfig.OBJECT_CACHE_SIZE_KEY + "\" (default " + ObjectCacheConfig.OBJECT_CACHE_SIZE_DEFAULT + ")," + |
| "\"" + ObjectCacheConfig.OBJECT_CACHE_EXPIRATION_KEY + "\" (default " + ObjectCacheConfig.OBJECT_CACHE_EXPIRATION_MIN_DEFAULT + ")," + |
| "\"" + ObjectCacheConfig.OBJECT_CACHE_TIME_UNIT_KEY+ "\" (default MINUTES)." + |
| "Note, if these are changed in global config, topology restart is required." |
| , params = { |
| "path - The path in HDFS to the serialized object" |
| } |
| , returns="The deserialized object." |
| ) |
| public class ObjectGet implements StellarFunction { |
| private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); |
| |
| private ObjectCache objectCache; |
| |
| @Override |
| public Object apply(List<Object> args, Context context) throws ParseException { |
| if(!isInitialized()) { |
| return null; |
| } |
| if(args.size() < 1) { |
| return null; |
| } |
| Object o = args.get(0); |
| if(o == null) { |
| return null; |
| } |
| if(o instanceof String) { |
| return objectCache.get((String) o); |
| } |
| else { |
| throw new IllegalStateException("Unable to retrieve " + o + " as it is not a path"); |
| } |
| } |
| |
| @Override |
| public void initialize(Context context) { |
| Map<String, Object> config = getConfig(context); |
| objectCache = new ObjectCache(); |
| objectCache.initialize(new ObjectCacheConfig(config)); |
| } |
| |
| @Override |
| public boolean isInitialized() { |
| return objectCache != null && objectCache.isInitialized(); |
| } |
| |
| protected Map<String, Object> getConfig(Context context) { |
| return (Map<String, Object>) context.getCapability(Context.Capabilities.GLOBAL_CONFIG, false).orElse(new HashMap<>()); |
| } |
| } |