ExecuteAction.java

/*
 * Copyright (c) 2009-present the original author or authors.
 *
 * 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 com.planet57.gshell.commands.shell;

import java.io.File;
import java.util.List;

import com.planet57.gshell.command.Command;
import com.planet57.gshell.command.CommandContext;
import com.planet57.gshell.util.io.IO;
import com.planet57.gshell.command.CommandActionSupport;
import com.planet57.gshell.util.cli2.Argument;
import com.planet57.gshell.util.cli2.Option;
import com.planet57.gshell.variables.VariableNames;
import com.planet57.gshell.variables.Variables;
import org.apache.tools.ant.taskdefs.PumpStreamHandler;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

/**
 * Execute system processes.
 *
 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
 * @since 2.0
 */
@Command(name = "exec", description = "Execute system processes")
public class ExecuteAction
    extends CommandActionSupport
{
  @Nullable
  @Option(name = "d", longName = "directory", description = "Directory to execute command", token = "DIR")
  private File directory;

  @Option(longName = "newenvironment", description = "Do not propagate environment variables")
  private boolean newenvironment = false;

  @Argument(required = true, description = "Process arguments", token = "ARGUMENTS")
  private List<String> args;

  // TODO: Consider adapting more of ant exec to support more features?

  @Override
  public Object execute(@Nonnull final CommandContext context) throws Exception {
    IO io = context.getIo();
    Variables variables = context.getVariables();

    // TODO: args may need special handling for ~/ as this won't translate to executable

    log.debug("Executing: {}", args);

    ProcessBuilder builder = new ProcessBuilder()
      .command(args)
      .inheritIO();

    File dir = directory;
    if (dir == null) {
      dir = variables.require(VariableNames.SHELL_USER_DIR, File.class);
    }
    log.debug("Directory: {}", dir);
    builder.directory(dir);

    if (!newenvironment) {
      log.debug("Propagating environment variables");
      builder.environment().putAll(System.getenv());
    }

    Process p = builder.start();

    PumpStreamHandler handler = new PumpStreamHandler(io.streams.out, io.streams.err);
    handler.setProcessInputStream(p.getOutputStream());
    handler.setProcessOutputStream(p.getInputStream());
    handler.setProcessErrorStream(p.getErrorStream());

    handler.start();

    log.debug("Waiting for process to exit...");

    int exitCode = p.waitFor();

    log.debug("Process exited w/code: {}", exitCode);

    handler.stop();

    return exitCode;
  }
}