Java tutorial
/* * Copyright 2014 Cask Data, Inc. * * Licensed 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 co.cask.cdap.internal.app.runtime.distributed; import co.cask.cdap.app.program.Program; import co.cask.cdap.app.program.Programs; import co.cask.cdap.app.runtime.ProgramController; import co.cask.cdap.app.runtime.ProgramOptions; import co.cask.cdap.app.runtime.ProgramRunner; import co.cask.cdap.common.conf.CConfiguration; import co.cask.cdap.common.conf.Constants; import co.cask.cdap.common.twill.AbortOnTimeoutEventHandler; import co.cask.cdap.data.security.HBaseTokenUtils; import co.cask.cdap.data2.util.hbase.HBaseTableUtilFactory; import com.google.common.base.Charsets; import com.google.common.base.Throwables; import com.google.common.io.Files; import com.google.common.io.InputSupplier; import com.google.common.util.concurrent.Service; import com.google.gson.Gson; import org.apache.commons.io.FileUtils; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.security.Credentials; import org.apache.twill.api.EventHandler; import org.apache.twill.api.TwillApplication; import org.apache.twill.api.TwillController; import org.apache.twill.api.TwillPreparer; import org.apache.twill.api.TwillRunner; import org.apache.twill.api.logging.PrinterLogHandler; import org.apache.twill.common.ServiceListenerAdapter; import org.apache.twill.common.Threads; import org.apache.twill.filesystem.LocalLocationFactory; import org.apache.twill.filesystem.Location; import org.apache.twill.yarn.YarnSecureStore; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.io.Writer; import java.util.concurrent.atomic.AtomicBoolean; /** * Defines the base framework for starting {@link Program} in the cluster. */ public abstract class AbstractDistributedProgramRunner implements ProgramRunner { private static final Logger LOG = LoggerFactory.getLogger(AbstractDistributedProgramRunner.class); private final TwillRunner twillRunner; private final Configuration hConf; private final CConfiguration cConf; protected final EventHandler eventHandler; /** * An interface for launching TwillApplication. Used by sub-classes only. */ protected interface ApplicationLauncher { TwillController launch(TwillApplication twillApplication); } protected AbstractDistributedProgramRunner(TwillRunner twillRunner, Configuration hConf, CConfiguration cConf) { this.twillRunner = twillRunner; this.hConf = hConf; this.cConf = cConf; this.eventHandler = createEventHandler(cConf); } protected EventHandler createEventHandler(CConfiguration cConf) { return new AbortOnTimeoutEventHandler( cConf.getLong(Constants.CFG_TWILL_NO_CONTAINER_TIMEOUT, Long.MAX_VALUE)); } @Override public final ProgramController run(final Program program, final ProgramOptions options) { final File hConfFile; final File cConfFile; final Program copiedProgram; final File programDir; // Temp directory for unpacking the program try { // Copy config files and program jar to local temp, and ask Twill to localize it to container. // What Twill does is to save those files in HDFS and keep using them during the lifetime of application. // Twill will manage the cleanup of those files in HDFS. hConfFile = saveHConf(hConf, File.createTempFile("hConf", ".xml")); cConfFile = saveCConf(cConf, File.createTempFile("cConf", ".xml")); programDir = Files.createTempDir(); copiedProgram = copyProgramJar(program, programDir); } catch (IOException e) { throw Throwables.propagate(e); } final String runtimeArgs = new Gson().toJson(options.getUserArguments()); // Obtains and add the HBase delegation token as well (if in non-secure mode, it's a no-op) // Twill would also ignore it if it is not running in secure mode. // The HDFS token should already obtained by Twill. return launch(copiedProgram, options, hConfFile, cConfFile, new ApplicationLauncher() { @Override public TwillController launch(TwillApplication twillApplication) { TwillPreparer twillPreparer = twillRunner.prepare(twillApplication); if (options.isDebug()) { LOG.info("Starting {} with debugging enabled.", program.getId()); twillPreparer.enableDebugging(); } TwillController twillController = twillPreparer .withDependencies(new HBaseTableUtilFactory().get().getClass()) .addLogHandler(new PrinterLogHandler(new PrintWriter(System.out))) .addSecureStore( YarnSecureStore.create(HBaseTokenUtils.obtainToken(hConf, new Credentials()))) .withApplicationArguments(String.format("--%s", RunnableOptions.JAR), copiedProgram.getJarLocation().getName(), String.format("--%s", RunnableOptions.RUNTIME_ARGS), runtimeArgs) .start(); return addCleanupListener(twillController, hConfFile, cConfFile, copiedProgram, programDir); } }); } /** * Sub-class overrides this method to launch the twill application. */ protected abstract ProgramController launch(Program program, ProgramOptions options, File hConfFile, File cConfFile, ApplicationLauncher launcher); private File saveHConf(Configuration conf, File file) throws IOException { Writer writer = Files.newWriter(file, Charsets.UTF_8); try { conf.writeXml(writer); } finally { writer.close(); } return file; } private File saveCConf(CConfiguration conf, File file) throws IOException { Writer writer = Files.newWriter(file, Charsets.UTF_8); try { conf.writeXml(writer); } finally { writer.close(); } return file; } /** * Copies the program jar to a local temp file and return a {@link Program} instance * with {@link Program#getJarLocation()} points to the local temp file. */ private Program copyProgramJar(final Program program, File programDir) throws IOException { File tempJar = File.createTempFile(program.getName(), ".jar"); Files.copy(new InputSupplier<InputStream>() { @Override public InputStream getInput() throws IOException { return program.getJarLocation().getInputStream(); } }, tempJar); final Location jarLocation = new LocalLocationFactory().create(tempJar.toURI()); return Programs.createWithUnpack(jarLocation, programDir); } /** * Adds a listener to the given TwillController to delete local temp files when the program has started/terminated. * The local temp files could be removed once the program is started, since Twill would keep the files in * HDFS and no long needs the local temp files once program is started. * * @return The same TwillController instance. */ private TwillController addCleanupListener(TwillController controller, final File hConfFile, final File cConfFile, final Program program, final File programDir) { final AtomicBoolean deleted = new AtomicBoolean(false); controller.addListener(new ServiceListenerAdapter() { @Override public void running() { cleanup(); } @Override public void terminated(Service.State from) { cleanup(); } @Override public void failed(Service.State from, Throwable failure) { cleanup(); } private void cleanup() { if (deleted.compareAndSet(false, true)) { LOG.debug("Cleanup tmp files for {}: {} {} {}", program.getName(), hConfFile, cConfFile, program.getJarLocation().toURI()); hConfFile.delete(); cConfFile.delete(); try { program.getJarLocation().delete(); } catch (IOException e) { LOG.warn("Failed to delete program jar {}", program.getJarLocation().toURI(), e); } try { FileUtils.deleteDirectory(programDir); } catch (IOException e) { LOG.warn("Failed to delete program directory {}", programDir, e); } } } }, Threads.SAME_THREAD_EXECUTOR); return controller; } }