Java tutorial
/* * Copyright 2012-2015 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.cli; import co.cask.cdap.cli.command.system.HelpCommand; import co.cask.cdap.cli.command.system.SearchCommandsCommand; import co.cask.cdap.cli.commandset.DefaultCommands; import co.cask.cdap.cli.completer.supplier.EndpointSupplier; import co.cask.cdap.cli.util.FilePathResolver; import co.cask.cdap.cli.util.InstanceURIParser; import co.cask.cdap.cli.util.table.AltStyleTableRenderer; import co.cask.cdap.cli.util.table.TableRenderer; import co.cask.cdap.client.config.ClientConfig; import co.cask.cdap.client.config.ConnectionConfig; import co.cask.cdap.client.exception.DisconnectedException; import co.cask.cdap.common.conf.CConfiguration; import co.cask.cdap.proto.Id; import co.cask.common.cli.CLI; import co.cask.common.cli.Command; import co.cask.common.cli.CommandSet; import co.cask.common.cli.exception.CLIExceptionHandler; import co.cask.common.cli.exception.InvalidCommandException; import com.google.common.annotations.VisibleForTesting; import com.google.common.base.Charsets; import com.google.common.base.Joiner; import com.google.common.base.Supplier; import com.google.common.collect.ImmutableList; import com.google.common.collect.Iterables; import com.google.common.io.Files; import com.google.inject.AbstractModule; import com.google.inject.Guice; import com.google.inject.Injector; import jline.console.completer.Completer; import org.apache.commons.cli.BasicParser; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Option; import org.apache.commons.cli.OptionGroup; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import java.io.File; import java.io.IOException; import java.io.PrintStream; import java.net.ConnectException; import java.net.URI; import java.net.URISyntaxException; import java.util.List; import java.util.Map; import javax.net.ssl.SSLHandshakeException; /** * Main class for the CDAP CLI. */ public class CLIMain { private static final boolean DEFAULT_VERIFY_SSL = true; private static final boolean DEFAULT_AUTOCONNECT = true; @VisibleForTesting public static final Option HELP_OPTION = new Option("h", "help", false, "Print the usage message."); @VisibleForTesting public static final Option URI_OPTION = new Option("u", "uri", true, "CDAP instance URI to interact with in" + " the format \"[http[s]://]<hostname>[:<port>[/<namespace>]]\"." + " Defaults to \"" + getDefaultURI().toString() + "\"."); @VisibleForTesting public static final Option VERIFY_SSL_OPTION = new Option("v", "verify-ssl", true, "If \"true\", verify SSL certificate when making requests." + " Defaults to \"" + DEFAULT_VERIFY_SSL + "\"."); @VisibleForTesting public static final Option AUTOCONNECT_OPTION = new Option("a", "autoconnect", true, "If \"true\", try provided connection" + " (from " + URI_OPTION.getLongOpt() + ")" + " upon launch or try default connection if none provided." + " Defaults to \"" + DEFAULT_AUTOCONNECT + "\"."); @VisibleForTesting public static final Option DEBUG_OPTION = new Option("d", "debug", false, "Print exception stack traces."); private static final Option SCRIPT_OPTION = new Option("s", "script", true, "Execute a file containing a series of CLI commands, line-by-line."); private final CLI cli; private final Iterable<CommandSet<Command>> commands; private final CLIConfig cliConfig; private final Injector injector; private final LaunchOptions options; private final FilePathResolver filePathResolver; public CLIMain(final LaunchOptions options, final CLIConfig cliConfig) throws URISyntaxException, IOException { this.options = options; this.cliConfig = cliConfig; cliConfig.getClientConfig().setVerifySSLCert(options.isVerifySSL()); injector = Guice.createInjector(new AbstractModule() { @Override protected void configure() { bind(LaunchOptions.class).toInstance(options); bind(CConfiguration.class).toInstance(CConfiguration.create()); bind(PrintStream.class).toInstance(cliConfig.getOutput()); bind(CLIConfig.class).toInstance(cliConfig); bind(ClientConfig.class).toInstance(cliConfig.getClientConfig()); } }); this.commands = ImmutableList.of(injector.getInstance(DefaultCommands.class), new CommandSet<>(ImmutableList.<Command>of(new HelpCommand(getCommandsSupplier(), cliConfig), new SearchCommandsCommand(getCommandsSupplier(), cliConfig)))); filePathResolver = injector.getInstance(FilePathResolver.class); Map<String, Completer> completers = injector.getInstance(DefaultCompleters.class).get(); cli = new CLI<>(Iterables.concat(commands), completers); cli.setExceptionHandler(new CLIExceptionHandler<Exception>() { @Override public boolean handleException(PrintStream output, Exception e, int timesRetried) { if (e instanceof SSLHandshakeException) { output.printf("To ignore this error, set \"--%s false\" when starting the CLI\n", VERIFY_SSL_OPTION.getLongOpt()); } else if (e instanceof InvalidCommandException) { InvalidCommandException ex = (InvalidCommandException) e; output.printf("Invalid command '%s'. Enter 'help' for a list of commands\n", ex.getInput()); } else if (e instanceof DisconnectedException || e instanceof ConnectException) { cli.getReader().setPrompt("cdap (DISCONNECTED)> "); } else { output.println("Error: " + e.getMessage()); } if (options.isDebug()) { e.printStackTrace(output); } return false; } }); cli.addCompleterSupplier(injector.getInstance(EndpointSupplier.class)); cli.getReader().setExpandEvents(false); cliConfig.addHostnameChangeListener(new CLIConfig.ConnectionChangeListener() { @Override public void onConnectionChanged(CLIConnectionConfig config) { updateCLIPrompt(config); } }); } /** * Tries to autoconnect to the provided URI in options. */ public void tryAutoconnect() { InstanceURIParser instanceURIParser = injector.getInstance(InstanceURIParser.class); if (options.isAutoconnect()) { try { CLIConnectionConfig connection = instanceURIParser.parse(options.getUri()); cliConfig.tryConnect(connection, cliConfig.getOutput(), options.isDebug()); } catch (Exception e) { if (options.isDebug()) { e.printStackTrace(cliConfig.getOutput()); } else { cliConfig.getOutput().println(e.getMessage()); } } } } public static URI getDefaultURI() { return ConnectionConfig.DEFAULT.getURI(); } public FilePathResolver getFilePathResolver() { return filePathResolver; } private String limit(String string, int maxLength) { if (string.length() <= maxLength) { return string; } if (string.length() >= 4) { return string.substring(0, string.length() - 3) + "..."; } else { return string; } } private void updateCLIPrompt(CLIConnectionConfig config) { cli.getReader().setPrompt(getPrompt(config)); } public String getPrompt(CLIConnectionConfig config) { try { return "cdap (" + config.getURI().resolve("/" + config.getNamespace()) + ")> "; } catch (DisconnectedException e) { return "cdap (DISCONNECTED)> "; } } public TableRenderer getTableRenderer() { return cliConfig.getTableRenderer(); } public CLI getCLI() { return this.cli; } public Supplier<Iterable<CommandSet<Command>>> getCommandsSupplier() { return new Supplier<Iterable<CommandSet<Command>>>() { @Override public Iterable<CommandSet<Command>> get() { return commands; } }; } public static void main(String[] args) { final PrintStream output = System.out; Options options = getOptions(); CLIMainArgs cliMainArgs = CLIMainArgs.parse(args, options); CommandLineParser parser = new BasicParser(); try { CommandLine command = parser.parse(options, cliMainArgs.getOptionTokens()); if (command.hasOption(HELP_OPTION.getOpt())) { usage(); System.exit(0); } LaunchOptions launchOptions = LaunchOptions.builder() .setUri(command.getOptionValue(URI_OPTION.getOpt(), getDefaultURI().toString())) .setDebug(command.hasOption(DEBUG_OPTION.getOpt())) .setVerifySSL(parseBooleanOption(command, VERIFY_SSL_OPTION, DEFAULT_VERIFY_SSL)) .setAutoconnect(parseBooleanOption(command, AUTOCONNECT_OPTION, DEFAULT_AUTOCONNECT)).build(); String scriptFile = command.getOptionValue(SCRIPT_OPTION.getOpt(), ""); boolean hasScriptFile = command.hasOption(SCRIPT_OPTION.getOpt()); String[] commandArgs = cliMainArgs.getCommandTokens(); try { ClientConfig clientConfig = ClientConfig.builder().setConnectionConfig(null).build(); final CLIConfig cliConfig = new CLIConfig(clientConfig, output, new AltStyleTableRenderer()); CLIMain cliMain = new CLIMain(launchOptions, cliConfig); CLI cli = cliMain.getCLI(); cliMain.tryAutoconnect(); CLIConnectionConfig connectionConfig = new CLIConnectionConfig( cliConfig.getClientConfig().getConnectionConfig(), Id.Namespace.DEFAULT, null); cliMain.updateCLIPrompt(connectionConfig); if (hasScriptFile) { File script = cliMain.getFilePathResolver().resolvePathToFile(scriptFile); if (!script.exists()) { output.println("ERROR: Script file '" + script.getAbsolutePath() + "' does not exist"); System.exit(1); } List<String> scriptLines = Files.readLines(script, Charsets.UTF_8); for (String scriptLine : scriptLines) { output.print(cliMain.getPrompt(connectionConfig)); output.println(scriptLine); cli.execute(scriptLine, output); output.println(); } } else if (commandArgs.length == 0) { cli.startInteractiveMode(output); } else { cli.execute(Joiner.on(" ").join(commandArgs), output); } } catch (Exception e) { e.printStackTrace(output); } } catch (ParseException e) { output.println(e.getMessage()); usage(); } } private static boolean parseBooleanOption(CommandLine command, Option option, boolean defaultValue) { String value = command.getOptionValue(option.getOpt(), Boolean.toString(defaultValue)); return "true".equals(value); } @VisibleForTesting public static Options getOptions() { Options options = new Options(); addOptionalOption(options, HELP_OPTION); addOptionalOption(options, URI_OPTION); addOptionalOption(options, VERIFY_SSL_OPTION); addOptionalOption(options, AUTOCONNECT_OPTION); addOptionalOption(options, DEBUG_OPTION); addOptionalOption(options, SCRIPT_OPTION); return options; } private static void addOptionalOption(Options options, Option option) { OptionGroup optionalGroup = new OptionGroup(); optionalGroup.setRequired(false); optionalGroup.addOption(option); options.addOptionGroup(optionalGroup); } private static void usage() { HelpFormatter formatter = new HelpFormatter(); String args = "[--autoconnect <true|false>] " + "[--debug] " + "[--help] " + "[--verify-ssl <true|false>] " + "[--uri <uri>]" + "[--script <script-file>]"; formatter.printHelp("cdap-cli.sh " + args, getOptions()); System.exit(0); } }