org.apache.ambari.server.api.services.stackadvisor.StackAdvisorRunner.java Source code

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Here is the source code for org.apache.ambari.server.api.services.stackadvisor.StackAdvisorRunner.java

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/**
 * 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.ambari.server.api.services.stackadvisor;

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

import org.apache.ambari.server.api.services.stackadvisor.commands.StackAdvisorCommandType;
import org.apache.commons.io.FileUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.inject.Singleton;

@Singleton
public class StackAdvisorRunner {

    private final static Logger LOG = LoggerFactory.getLogger(StackAdvisorRunner.class);

    /**
     * Runs stack_advisor.py script in the specified {@code actionDirectory}.
     *
     * @param script stack advisor script
     * @param saCommandType {@link StackAdvisorCommandType} to run.
     * @param actionDirectory directory for the action
     */
    public void runScript(String script, StackAdvisorCommandType saCommandType, File actionDirectory)
            throws StackAdvisorException {
        LOG.info(
                String.format("Script=%s, actionDirectory=%s, command=%s", script, actionDirectory, saCommandType));

        String outputFile = actionDirectory + File.separator + "stackadvisor.out";
        String errorFile = actionDirectory + File.separator + "stackadvisor.err";

        ProcessBuilder builder = prepareShellCommand(script, saCommandType, actionDirectory, outputFile, errorFile);

        try {
            Process process = builder.start();

            try {
                LOG.info("Stack-advisor output={}, error={}", outputFile, errorFile);

                int exitCode = process.waitFor();
                String outMessage;
                String errMessage = null;
                try {
                    outMessage = FileUtils.readFileToString(new File(outputFile)).trim();
                    errMessage = FileUtils.readFileToString(new File(errorFile)).trim();
                    LOG.info("Stack advisor output files");
                    LOG.info("    advisor script stdout: {}", outMessage);
                    LOG.info("    advisor script stderr: {}", errMessage);
                } catch (IOException io) {
                    LOG.error("Error in reading script log files", io);
                }
                if (exitCode > 0) {
                    String errorMessage;
                    if (errMessage != null) {
                        // We want to get the last line.
                        int index = errMessage.lastIndexOf("\n");
                        if (index > 0 && index == (errMessage.length() - 1)) {
                            index = errMessage.lastIndexOf("\n", index - 1); // sentence ended with newline
                        }
                        if (index > -1) {
                            errMessage = errMessage.substring(index + 1).trim();
                        }
                        errorMessage = errMessage;
                    } else {
                        errorMessage = "Error occurred during stack advisor execution";
                    }
                    switch (exitCode) {
                    case 1:
                        throw new StackAdvisorRequestException(errorMessage);
                    case 2:
                        throw new StackAdvisorException(errorMessage);
                    }
                }
            } finally {
                process.destroy();
            }
        } catch (StackAdvisorException ex) {
            throw ex;
        } catch (Exception ioe) {
            String message = "Error executing stack advisor: ";
            LOG.error(message, ioe);
            throw new StackAdvisorException(message + ioe.getMessage());
        }
    }

    /**
     * Gets an instance of a {@link ProcessBuilder} that's ready to execute the
     * shell command to run the stack advisor script. This will take the
     * environment variables from the current process.
     *
     * @param script
     * @param saCommandType
     * @param actionDirectory
     * @param outputFile
     * @param errorFile
     * @return
     */
    ProcessBuilder prepareShellCommand(String script, StackAdvisorCommandType saCommandType, File actionDirectory,
            String outputFile, String errorFile) {
        String hostsFile = actionDirectory + File.separator + "hosts.json";
        String servicesFile = actionDirectory + File.separator + "services.json";

        // includes the original command plus the arguments for it
        List<String> builderParameters = new ArrayList<String>();
        if (System.getProperty("os.name").contains("Windows")) {
            builderParameters.add("cmd");
            builderParameters.add("/c");
        } else {
            builderParameters.add("sh");
            builderParameters.add("-c");
        }

        // for the 3rd argument, build a single parameter since we use -c
        // ProcessBuilder doesn't support output redirection until JDK 1.7
        String commandStringParameters[] = new String[] { script, saCommandType.toString(), hostsFile, servicesFile,
                "1>", outputFile, "2>", errorFile };

        StringBuilder commandString = new StringBuilder();
        for (String command : commandStringParameters) {
            commandString.append(command).append(" ");
        }

        builderParameters.add(commandString.toString());

        LOG.debug("Stack advisor command is {}", builderParameters);

        return new ProcessBuilder(builderParameters);
    }
}