org.apache.zeppelin.pig.PigInterpreter.java Source code

Introduction

Here is the source code for org.apache.zeppelin.pig.PigInterpreter.java

Source

/*
 * 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.zeppelin.pig;

import org.apache.commons.io.output.ByteArrayOutputStream;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.exception.ExceptionUtils;
import org.apache.pig.PigServer;
import org.apache.pig.impl.logicalLayer.FrontendException;
import org.apache.pig.tools.pigstats.*;
import org.apache.zeppelin.interpreter.InterpreterContext;
import org.apache.zeppelin.interpreter.InterpreterResult;
import org.apache.zeppelin.interpreter.InterpreterResult.Code;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.io.PrintStream;
import java.util.*;

/**
 * Pig interpreter for Zeppelin.
 */
public class PigInterpreter extends BasePigInterpreter {
    private static Logger LOGGER = LoggerFactory.getLogger(PigInterpreter.class);

    private PigServer pigServer;
    private boolean includeJobStats = false;

    public PigInterpreter(Properties property) {
        super(property);
    }

    @Override
    public void open() {
        String execType = getProperty("zeppelin.pig.execType");
        if (execType == null) {
            execType = "mapreduce";
        }
        String includeJobStats = getProperty("zeppelin.pig.includeJobStats");
        if (includeJobStats != null) {
            this.includeJobStats = Boolean.parseBoolean(includeJobStats);
        }
        try {
            pigServer = new PigServer(execType);
            for (Map.Entry entry : getProperty().entrySet()) {
                if (!entry.getKey().toString().startsWith("zeppelin.")) {
                    pigServer.getPigContext().getProperties().setProperty(entry.getKey().toString(),
                            entry.getValue().toString());
                }
            }
        } catch (IOException e) {
            LOGGER.error("Fail to initialize PigServer", e);
            throw new RuntimeException("Fail to initialize PigServer", e);
        }
    }

    @Override
    public void close() {
        pigServer = null;
    }

    @Override
    public InterpreterResult interpret(String cmd, InterpreterContext contextInterpreter) {
        // remember the origial stdout, because we will redirect stdout to capture
        // the pig dump output.
        PrintStream originalStdOut = System.out;
        ByteArrayOutputStream bytesOutput = new ByteArrayOutputStream();
        File tmpFile = null;
        try {
            pigServer.setJobName(createJobName(cmd, contextInterpreter));
            tmpFile = PigUtils.createTempPigScript(cmd);
            System.setOut(new PrintStream(bytesOutput));
            // each thread should its own ScriptState & PigStats
            ScriptState.start(pigServer.getPigContext().getExecutionEngine().instantiateScriptState());
            // reset PigStats, otherwise you may get the PigStats of last job in the same thread
            // because PigStats is ThreadLocal variable
            PigStats.start(pigServer.getPigContext().getExecutionEngine().instantiatePigStats());
            PigScriptListener scriptListener = new PigScriptListener();
            ScriptState.get().registerListener(scriptListener);
            listenerMap.put(contextInterpreter.getParagraphId(), scriptListener);
            pigServer.registerScript(tmpFile.getAbsolutePath());
        } catch (IOException e) {
            if (e instanceof FrontendException) {
                FrontendException fe = (FrontendException) e;
                if (!fe.getMessage().contains("Backend error :")) {
                    // If the error message contains "Backend error :", that means the exception is from
                    // backend.
                    LOGGER.error("Fail to run pig script.", e);
                    return new InterpreterResult(Code.ERROR, ExceptionUtils.getStackTrace(e));
                }
            }
            PigStats stats = PigStats.get();
            if (stats != null) {
                String errorMsg = PigUtils.extactJobStats(stats);
                if (errorMsg != null) {
                    LOGGER.error("Fail to run pig script, " + errorMsg);
                    return new InterpreterResult(Code.ERROR, errorMsg);
                }
            }
            LOGGER.error("Fail to run pig script.", e);
            return new InterpreterResult(Code.ERROR, ExceptionUtils.getStackTrace(e));
        } finally {
            System.setOut(originalStdOut);
            listenerMap.remove(contextInterpreter.getParagraphId());
            if (tmpFile != null) {
                tmpFile.delete();
            }
        }
        StringBuilder outputBuilder = new StringBuilder();
        PigStats stats = PigStats.get();
        if (stats != null && includeJobStats) {
            String jobStats = PigUtils.extactJobStats(stats);
            if (jobStats != null) {
                outputBuilder.append(jobStats);
            }
        }
        outputBuilder.append(bytesOutput.toString());
        return new InterpreterResult(Code.SUCCESS, outputBuilder.toString());
    }

    public PigServer getPigServer() {
        return pigServer;
    }

}