samza-sql-shell/src/main/java/org/apache/samza/sql/client/cli/CliShell.java - samza - Git at Google

 /*
  * 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.samza.sql.client.cli;

 import java.io.IOException;
 import java.io.PrintWriter;
 import java.util.ArrayList;
 import java.util.List;
 import org.apache.samza.sql.client.exceptions.CommandHandlerException;
 import org.apache.samza.sql.client.impl.CliCommandHandler;
 import org.apache.samza.sql.client.impl.CliCommandType;
 import org.apache.samza.sql.client.interfaces.CommandHandler;
 import org.apache.samza.sql.client.interfaces.ExecutionContext;
 import org.apache.samza.sql.client.exceptions.ExecutorException;
 import org.apache.samza.sql.client.interfaces.SqlExecutor;
 import org.apache.samza.sql.client.exceptions.CliException;
 import org.apache.samza.sql.client.util.CliUtil;
 import org.jline.reader.EndOfFileException;
 import org.jline.reader.LineReader;
 import org.jline.reader.LineReaderBuilder;
 import org.jline.reader.UserInterruptException;
 import org.jline.reader.impl.DefaultParser;
 import org.jline.reader.impl.completer.StringsCompleter;
 import org.jline.terminal.Terminal;
 import org.jline.terminal.TerminalBuilder;
 import org.jline.utils.AttributedStringBuilder;
 import org.jline.utils.AttributedStyle;
 import org.jline.utils.InfoCmp;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 /**
  * The shell UI.
  */
 public class CliShell {
   private static final Logger LOG = LoggerFactory.getLogger(CliShell.class);
   private final Terminal terminal;
   private final PrintWriter writer;
   private final LineReader lineReader;
   private final String firstPrompt;
   private SqlExecutor executor;
   private List<CommandHandler> commandHandlers;
   private final ExecutionContext exeContext;
   private boolean keepRunning = true;

   CliShell(CliEnvironment environment) throws ExecutorException {
     if (environment == null) {
       throw new IllegalArgumentException();
     }

     // Terminal
     try {
       terminal = TerminalBuilder.builder().name(CliConstants.WINDOW_TITLE).build();
     } catch (IOException e) {
       throw new CliException("Error when creating terminal", e);
     }

     // Terminal writer
     writer = terminal.writer();

     // LineReader
     final DefaultParser parser = new DefaultParser().eofOnEscapedNewLine(true).eofOnUnclosedQuote(true);
     lineReader = LineReaderBuilder.builder()
         .appName(CliConstants.APP_NAME)
         .terminal(terminal)
         .parser(parser)
         .highlighter(new CliHighlighter())
         .completer(new StringsCompleter(CliCommandType.getAllCommands()))
         .build();

     // Command Prompt
     firstPrompt = new AttributedStringBuilder().style(AttributedStyle.DEFAULT.foreground(AttributedStyle.YELLOW))
         .append(CliConstants.PROMPT_1ST + CliConstants.PROMPT_1ST_END)
         .toAnsi();

     // Execution context and executor
     executor = environment.getExecutor();
     exeContext = new ExecutionContext();
     executor.start(exeContext);

     // Command handlers
     if (commandHandlers == null) {
       commandHandlers = new ArrayList<>();
     }
     commandHandlers.add(new CliCommandHandler());
     commandHandlers.addAll(environment.getCommandHandlers());
     for (CommandHandler commandHandler : commandHandlers) {
       LOG.info("init commandHandler {}", commandHandler.getClass().getName());
       commandHandler.init(this, environment, terminal, exeContext);
     }
   }

   Terminal getTerminal() {
     return terminal;
   }

   SqlExecutor getExecutor() {
     return executor;
   }

   ExecutionContext getExeContext() {
     return exeContext;
   }

   /**
    * Actually run the shell. Does not return until user choose to exit.
    */
   void open(String message) {
     // Remember we cannot enter alternate screen mode here as there is only one alternate
     // screen and we need it to show streaming results. Clear the screen instead.
     clearScreen();
     writer.write(CliConstants.WELCOME_MESSAGE);
     printVersion();
     if (!CliUtil.isNullOrEmpty(message)) {
       writer.println(message);
     }
     writer.println();

     try {
       // Check if jna.jar exists in class path
       try {
         ClassLoader.getSystemClassLoader().loadClass("com.sun.jna.NativeLibrary");
       } catch (ClassNotFoundException e) {
         // Something's wrong. It could be a dumb terminal if neither jna nor jansi lib is there
         writer.write("Warning: jna.jar does NOT exist. It may lead to a dumb shell or a performance hit.\n");
       }

       while (keepRunning) {
         String line;
         try {
           line = lineReader.readLine(firstPrompt);
         } catch (UserInterruptException e) {
           continue;
         } catch (EndOfFileException e) {
           keepRunning = false;
           break;
         }

         if (CliUtil.isNullOrEmpty(line))
           continue;

         String helpCmdText = CliCommandType.HELP.getCommandName();
         if (line.toUpperCase().startsWith(helpCmdText)) {
           if (line.toLowerCase().trim().equals(helpCmdText)) {
             printHelpMessage();
           } else {
             CommandAndHandler commandAndHandler = findHandlerForCommand(line.substring(helpCmdText.length()));
             if (commandAndHandler.handler != null) {
               commandAndHandler.handler.handleCommand(commandAndHandler.handler.parseLine(line));
             } else {
               printHelpMessage();
             }
           }
           continue;
         }

         CommandAndHandler commandAndHandler = null;
         try {
           commandAndHandler = findHandlerForCommand(line);
           if (commandAndHandler.handler == null) {
             LOG.info("no commandHandler found for command {}", line);
             printHelpMessage();
             continue;
           }
           keepRunning = commandAndHandler.handler.handleCommand(commandAndHandler.command);
         } catch (CommandHandlerException e) {
           writer.println("Error: " + e);
           LOG.error("Error in {}: ", commandAndHandler.command.getCommandType(), e);
           writer.flush();
         }
       }
     } catch (Exception e) {
       writer.print(e.getClass().getSimpleName());
       writer.print(". ");
       writer.println(e.getMessage());
       e.printStackTrace(writer);
       writer.println();
       writer.println("We are sorry but SamzaSqlShell has encountered a problem and must stop.");
     }

     writer.write("Cleaning up... ");
     writer.flush();
     try {
       executor.stop(exeContext);
       writer.write("Done.\nBye.\n\n");
       writer.flush();
       terminal.close();
     } catch (IOException | ExecutorException e) {
       // Doesn't matter
     }
   }

   private void printVersion() {
     String version = String.format("Shell version %s, Executor is %s, version %s",
             this.getClass().getPackage().getImplementationVersion(),
             executor.getClass().getName(),
             executor.getVersion());
     writer.println(version);
   }

   private void clearScreen() {
     terminal.puts(InfoCmp.Capability.clear_screen);
   }

   private void printHelpMessage() {
     for (CommandHandler commandHandler : commandHandlers) {
       commandHandler.printHelpMessage();
     }
     writer.println("HELP <COMMAND> to get help for a specific command.");
     writer.flush();
   }

   private CommandAndHandler findHandlerForCommand(String line) {
     CommandHandler commandHandler = null;
     CliCommand parsedCommand = null;
     for (CommandHandler curCommandHandler : commandHandlers) {
       parsedCommand = curCommandHandler.parseLine(line);
       if (parsedCommand != null && !parsedCommand.getCommandType().getCommandName().equals(CliCommandType.INVALID_COMMAND.getCommandName())) {
         commandHandler = curCommandHandler;
         LOG.info("Found commandHandler {} to handle command {}", commandHandler.getClass().getName(),
             parsedCommand.getFullCommand());
         break;
       }
     }
     return new CommandAndHandler(parsedCommand, commandHandler);
   }

   class CommandAndHandler {
     CliCommand command;
     CommandHandler handler;

     CommandAndHandler(CliCommand aCommand, CommandHandler itsHandler) {
       command = aCommand;
       handler = itsHandler;
     }
   }
 }
	/*
	* 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.samza.sql.client.cli;

	import java.io.IOException;
	import java.io.PrintWriter;
	import java.util.ArrayList;
	import java.util.List;
	import org.apache.samza.sql.client.exceptions.CommandHandlerException;
	import org.apache.samza.sql.client.impl.CliCommandHandler;
	import org.apache.samza.sql.client.impl.CliCommandType;
	import org.apache.samza.sql.client.interfaces.CommandHandler;
	import org.apache.samza.sql.client.interfaces.ExecutionContext;
	import org.apache.samza.sql.client.exceptions.ExecutorException;
	import org.apache.samza.sql.client.interfaces.SqlExecutor;
	import org.apache.samza.sql.client.exceptions.CliException;
	import org.apache.samza.sql.client.util.CliUtil;
	import org.jline.reader.EndOfFileException;
	import org.jline.reader.LineReader;
	import org.jline.reader.LineReaderBuilder;
	import org.jline.reader.UserInterruptException;
	import org.jline.reader.impl.DefaultParser;
	import org.jline.reader.impl.completer.StringsCompleter;
	import org.jline.terminal.Terminal;
	import org.jline.terminal.TerminalBuilder;
	import org.jline.utils.AttributedStringBuilder;
	import org.jline.utils.AttributedStyle;
	import org.jline.utils.InfoCmp;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	/**
	* The shell UI.
	*/
	public class CliShell {
	private static final Logger LOG = LoggerFactory.getLogger(CliShell.class);
	private final Terminal terminal;
	private final PrintWriter writer;
	private final LineReader lineReader;
	private final String firstPrompt;
	private SqlExecutor executor;
	private List<CommandHandler> commandHandlers;
	private final ExecutionContext exeContext;
	private boolean keepRunning = true;

	CliShell(CliEnvironment environment) throws ExecutorException {
	if (environment == null) {
	throw new IllegalArgumentException();
	}

	// Terminal
	try {
	terminal = TerminalBuilder.builder().name(CliConstants.WINDOW_TITLE).build();
	} catch (IOException e) {
	throw new CliException("Error when creating terminal", e);
	}

	// Terminal writer
	writer = terminal.writer();

	// LineReader
	final DefaultParser parser = new DefaultParser().eofOnEscapedNewLine(true).eofOnUnclosedQuote(true);
	lineReader = LineReaderBuilder.builder()
	.appName(CliConstants.APP_NAME)
	.terminal(terminal)
	.parser(parser)
	.highlighter(new CliHighlighter())
	.completer(new StringsCompleter(CliCommandType.getAllCommands()))
	.build();

	// Command Prompt
	firstPrompt = new AttributedStringBuilder().style(AttributedStyle.DEFAULT.foreground(AttributedStyle.YELLOW))
	.append(CliConstants.PROMPT_1ST + CliConstants.PROMPT_1ST_END)
	.toAnsi();

	// Execution context and executor
	executor = environment.getExecutor();
	exeContext = new ExecutionContext();
	executor.start(exeContext);

	// Command handlers
	if (commandHandlers == null) {
	commandHandlers = new ArrayList<>();
	}
	commandHandlers.add(new CliCommandHandler());
	commandHandlers.addAll(environment.getCommandHandlers());
	for (CommandHandler commandHandler : commandHandlers) {
	LOG.info("init commandHandler {}", commandHandler.getClass().getName());
	commandHandler.init(this, environment, terminal, exeContext);
	}
	}

	Terminal getTerminal() {
	return terminal;
	}

	SqlExecutor getExecutor() {
	return executor;
	}

	ExecutionContext getExeContext() {
	return exeContext;
	}

	/**
	* Actually run the shell. Does not return until user choose to exit.
	*/
	void open(String message) {
	// Remember we cannot enter alternate screen mode here as there is only one alternate
	// screen and we need it to show streaming results. Clear the screen instead.
	clearScreen();
	writer.write(CliConstants.WELCOME_MESSAGE);
	printVersion();
	if (!CliUtil.isNullOrEmpty(message)) {
	writer.println(message);
	}
	writer.println();

	try {
	// Check if jna.jar exists in class path
	try {
	ClassLoader.getSystemClassLoader().loadClass("com.sun.jna.NativeLibrary");
	} catch (ClassNotFoundException e) {
	// Something's wrong. It could be a dumb terminal if neither jna nor jansi lib is there
	writer.write("Warning: jna.jar does NOT exist. It may lead to a dumb shell or a performance hit.\n");
	}

	while (keepRunning) {
	String line;
	try {
	line = lineReader.readLine(firstPrompt);
	} catch (UserInterruptException e) {
	continue;
	} catch (EndOfFileException e) {
	keepRunning = false;
	break;
	}

	if (CliUtil.isNullOrEmpty(line))
	continue;

	String helpCmdText = CliCommandType.HELP.getCommandName();
	if (line.toUpperCase().startsWith(helpCmdText)) {
	if (line.toLowerCase().trim().equals(helpCmdText)) {
	printHelpMessage();
	} else {
	CommandAndHandler commandAndHandler = findHandlerForCommand(line.substring(helpCmdText.length()));
	if (commandAndHandler.handler != null) {
	commandAndHandler.handler.handleCommand(commandAndHandler.handler.parseLine(line));
	} else {
	printHelpMessage();
	}
	}
	continue;
	}

	CommandAndHandler commandAndHandler = null;
	try {
	commandAndHandler = findHandlerForCommand(line);
	if (commandAndHandler.handler == null) {
	LOG.info("no commandHandler found for command {}", line);
	printHelpMessage();
	continue;
	}
	keepRunning = commandAndHandler.handler.handleCommand(commandAndHandler.command);
	} catch (CommandHandlerException e) {
	writer.println("Error: " + e);
	LOG.error("Error in {}: ", commandAndHandler.command.getCommandType(), e);
	writer.flush();
	}
	}
	} catch (Exception e) {
	writer.print(e.getClass().getSimpleName());
	writer.print(". ");
	writer.println(e.getMessage());
	e.printStackTrace(writer);
	writer.println();
	writer.println("We are sorry but SamzaSqlShell has encountered a problem and must stop.");
	}

	writer.write("Cleaning up... ");
	writer.flush();
	try {
	executor.stop(exeContext);
	writer.write("Done.\nBye.\n\n");
	writer.flush();
	terminal.close();
	} catch (IOException \| ExecutorException e) {
	// Doesn't matter
	}
	}

	private void printVersion() {
	String version = String.format("Shell version %s, Executor is %s, version %s",
	this.getClass().getPackage().getImplementationVersion(),
	executor.getClass().getName(),
	executor.getVersion());
	writer.println(version);
	}

	private void clearScreen() {
	terminal.puts(InfoCmp.Capability.clear_screen);
	}

	private void printHelpMessage() {
	for (CommandHandler commandHandler : commandHandlers) {
	commandHandler.printHelpMessage();
	}
	writer.println("HELP <COMMAND> to get help for a specific command.");
	writer.flush();
	}

	private CommandAndHandler findHandlerForCommand(String line) {
	CommandHandler commandHandler = null;
	CliCommand parsedCommand = null;
	for (CommandHandler curCommandHandler : commandHandlers) {
	parsedCommand = curCommandHandler.parseLine(line);
	if (parsedCommand != null && !parsedCommand.getCommandType().getCommandName().equals(CliCommandType.INVALID_COMMAND.getCommandName())) {
	commandHandler = curCommandHandler;
	LOG.info("Found commandHandler {} to handle command {}", commandHandler.getClass().getName(),
	parsedCommand.getFullCommand());
	break;
	}
	}
	return new CommandAndHandler(parsedCommand, commandHandler);
	}

	class CommandAndHandler {
	CliCommand command;
	CommandHandler handler;

	CommandAndHandler(CliCommand aCommand, CommandHandler itsHandler) {
	command = aCommand;
	handler = itsHandler;
	}
	}
	}