| /** |
| * 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 |
| * <p/> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p/> |
| * 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.atlas.impala.hook; |
| |
| import org.apache.atlas.plugin.classloader.AtlasPluginClassLoader; |
| import org.apache.impala.hooks.QueryCompleteContext; |
| import org.apache.impala.hooks.QueryEventHook; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * This class is used to convert lineage records from Impala to lineage notifications and |
| * send them to Atlas. |
| */ |
| public class ImpalaLineageHook implements QueryEventHook { |
| private static final Logger LOG = LoggerFactory.getLogger(ImpalaLineageHook.class); |
| |
| private static final String ATLAS_PLUGIN_TYPE_IMPALA = "impala"; |
| private static final String ATLAS_IMPALA_LINEAGE_HOOK_IMPL_CLASSNAME = |
| "org.apache.atlas.impala.hook.ImpalaHook"; |
| |
| private AtlasPluginClassLoader atlasPluginClassLoader = null; |
| private QueryEventHook impalaLineageHookImpl; |
| |
| public ImpalaLineageHook() { |
| } |
| |
| /** |
| * Execute Impala hook |
| */ |
| public void onQueryComplete(QueryCompleteContext context) { |
| LOG.debug("==> ImpalaLineageHook.onQueryComplete()"); |
| |
| try { |
| activatePluginClassLoader(); |
| impalaLineageHookImpl.onQueryComplete(context); |
| } catch (Exception ex) { |
| String errorMessage = String.format("Error in processing impala lineage: {}", context.getLineageGraph()); |
| LOG.error(errorMessage, ex); |
| } finally { |
| deactivatePluginClassLoader(); |
| } |
| |
| LOG.debug("<== ImpalaLineageHook.onQueryComplete()"); |
| } |
| |
| /** |
| * Initialization of Impala hook |
| */ |
| public void onImpalaStartup() { |
| LOG.debug("==> ImpalaLineageHook.onImpalaStartup()"); |
| |
| try { |
| atlasPluginClassLoader = AtlasPluginClassLoader.getInstance(ATLAS_PLUGIN_TYPE_IMPALA, this.getClass()); |
| |
| @SuppressWarnings("unchecked") |
| Class<QueryEventHook> cls = (Class<QueryEventHook>) Class |
| .forName(ATLAS_IMPALA_LINEAGE_HOOK_IMPL_CLASSNAME, true, atlasPluginClassLoader); |
| |
| activatePluginClassLoader(); |
| |
| impalaLineageHookImpl = cls.newInstance(); |
| impalaLineageHookImpl.onImpalaStartup(); |
| } catch (Exception excp) { |
| LOG.error("Error instantiating Atlas hook implementation for Impala lineage", excp); |
| } finally { |
| deactivatePluginClassLoader(); |
| } |
| |
| LOG.debug("<== ImpalaLineageHook.onImpalaStartup()"); |
| } |
| |
| private void activatePluginClassLoader() { |
| if (atlasPluginClassLoader != null) { |
| atlasPluginClassLoader.activate(); |
| } |
| } |
| |
| private void deactivatePluginClassLoader() { |
| if (atlasPluginClassLoader != null) { |
| atlasPluginClassLoader.deactivate(); |
| } |
| } |
| } |