| /* |
| * 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.knox.gateway.cm.descriptor; |
| |
| import java.io.File; |
| import java.io.FileFilter; |
| import java.io.IOException; |
| import java.nio.charset.StandardCharsets; |
| import java.nio.file.Files; |
| import java.nio.file.Path; |
| import java.nio.file.Paths; |
| import java.nio.file.attribute.FileTime; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.commons.io.FileUtils; |
| import org.apache.commons.io.filefilter.SuffixFileFilter; |
| import org.apache.commons.lang3.concurrent.BasicThreadFactory; |
| import org.apache.knox.gateway.ClouderaManagerIntegrationMessages; |
| import org.apache.knox.gateway.config.GatewayConfig; |
| import org.apache.knox.gateway.i18n.messages.MessagesFactory; |
| import org.apache.knox.gateway.util.JsonUtils; |
| |
| /** |
| * Monitoring KNOX_DESCRIPTOR_DIR for *.cm files - which is a Hadoop XML configuration - and processing those files if they were modified |
| * since the last time it they were processed |
| */ |
| public class ClouderaManagerDescriptorMonitor { |
| |
| private static final String CM_DESCRIPTOR_FILE_EXTENSION = ".cm"; |
| private static final ClouderaManagerIntegrationMessages LOG = MessagesFactory.get(ClouderaManagerIntegrationMessages.class); |
| private final String descriptorsDir; |
| private final long monitoringInterval; |
| private final ScheduledExecutorService executorService; |
| private FileTime lastReloadTime; |
| |
| public ClouderaManagerDescriptorMonitor(GatewayConfig gatewayConfig) { |
| this.descriptorsDir = gatewayConfig.getGatewayDescriptorsDir(); |
| this.monitoringInterval = gatewayConfig.getClouderaManagerDescriptorsMonitoringInterval(); |
| this.executorService = Executors.newSingleThreadScheduledExecutor(new BasicThreadFactory.Builder().namingPattern("ClouderaManagerDescriptorMonitor-%d").build()); |
| } |
| |
| public void setupMonitor() { |
| if (monitoringInterval > 0) { |
| executorService.scheduleAtFixedRate(() -> monitorClouderaManagerDescriptors(), 0, monitoringInterval, TimeUnit.MILLISECONDS); |
| LOG.monitoringClouderaManagerDescriptor(descriptorsDir); |
| } |
| } |
| |
| private void monitorClouderaManagerDescriptors() { |
| final File[] clouderaManagerDescriptorFiles = new File(descriptorsDir).listFiles((FileFilter) new SuffixFileFilter(CM_DESCRIPTOR_FILE_EXTENSION)); |
| for (File clouderaManagerDescriptorFile : clouderaManagerDescriptorFiles) { |
| monitorClouderaManagerDescriptor(Paths.get(clouderaManagerDescriptorFile.getAbsolutePath())); |
| } |
| } |
| |
| private void monitorClouderaManagerDescriptor(Path clouderaManagerDescriptorFile) { |
| try { |
| if (Files.isReadable(clouderaManagerDescriptorFile)) { |
| final FileTime lastModifiedTime = Files.getLastModifiedTime(clouderaManagerDescriptorFile); |
| if (lastReloadTime == null || lastReloadTime.compareTo(lastModifiedTime) < 0) { |
| lastReloadTime = lastModifiedTime; |
| processClouderaManagerDescriptor(clouderaManagerDescriptorFile.toString()); |
| } |
| } else { |
| LOG.failedToMonitorClouderaManagerDescriptor(clouderaManagerDescriptorFile.toString(), "File is not readable!", null); |
| } |
| } catch (IOException e) { |
| LOG.failedToMonitorClouderaManagerDescriptor(clouderaManagerDescriptorFile.toString(), e.getMessage(), e); |
| } |
| } |
| |
| private void processClouderaManagerDescriptor(String descriptorFilePath) { |
| ClouderaManagerDescriptorParser.parse(descriptorFilePath).forEach(simpleDescriptor -> { |
| try { |
| final File knoxDescriptorFile = new File(descriptorsDir, simpleDescriptor.getName() + ".json"); |
| FileUtils.writeStringToFile(knoxDescriptorFile, JsonUtils.renderAsJsonString(simpleDescriptor), StandardCharsets.UTF_8); |
| } catch (IOException e) { |
| LOG.failedToProduceKnoxDescriptor(e.getMessage(), e); |
| } |
| }); |
| } |
| } |