Apache Storm在Twitter上的應(yīng)用

在本章中，我們將討論Apache Storm的實(shí)時(shí)應(yīng)用程序。我們將看到Storm如何在Twitter中使用。

Twitter

Twitter是一種在線社交網(wǎng)絡(luò)服務(wù)，提供發(fā)送和接收用戶推文的平臺(tái)。注冊(cè)用戶可以閱讀和發(fā)布tweet，但未注冊(cè)的用戶只能閱讀tweets。 Hashtag用于按關(guān)鍵字在相關(guān)關(guān)鍵字之前附加＃來對(duì)tweet進(jìn)行分類。現(xiàn)在讓我們來看一個(gè)實(shí)時(shí)場(chǎng)景，找到每個(gè)主題使用最多的hashtag。

Spout創(chuàng)建

spout的目的是盡快收到人們提交的tweets。Twitter提供了“Twitter Streaming API”，一個(gè)基于Web服務(wù)的工具，用于實(shí)時(shí)檢索人們提交的tweets。Twitter Streaming API可以使用任何編程語言訪問。

twitter4j是一個(gè)開源的非官方Java庫(kù)，它提供了一個(gè)基于Java的模塊，可以輕松訪問Twitter Streaming API。twitter4j提供了一個(gè)基于監(jiān)聽器的框架來訪問tweet。要訪問Twitter Streaming API，我們需要登錄Twitter開發(fā)人員帳戶，并獲取以下OAuth身份驗(yàn)證詳細(xì)信息。

• Customerkey
• CustomerSecret
• 的accessToken
• AccessTookenSecret

Storm在其入門套件中提供了一個(gè)twitter spout，TwitterSampleSpout。我們將使用它來檢索tweet。該郵件需要OAuth身份驗(yàn)證詳細(xì)信息和至少一個(gè)關(guān)鍵字。該spout將發(fā)出基于關(guān)鍵字的實(shí)時(shí)tweet。完整的程序代碼如下。

編碼：TwitterSampleSpout.java

import java.util.Map;
import java.util.concurrent.LinkedBlockingQueue;

import twitter4j.FilterQuery;
import twitter4j.StallWarning;
import twitter4j.Status;
import twitter4j.StatusDeletionNotice;
import twitter4j.StatusListener;

import twitter4j.TwitterStream;
import twitter4j.TwitterStreamFactory;
import twitter4j.auth.AccessToken;
import twitter4j.conf.ConfigurationBuilder;

import backtype.storm.Config;
import backtype.storm.spout.SpoutOutputCollector;

import backtype.storm.task.TopologyContext;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.topology.base.BaseRichSpout;
import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;

import backtype.storm.utils.Utils;

@SuppressWarnings("serial")
public class TwitterSampleSpout extends BaseRichSpout {
   SpoutOutputCollector _collector;
   LinkedBlockingQueue<Status> queue = null;
   TwitterStream _twitterStream;
		
   String consumerKey;
   String consumerSecret;
   String accessToken;
   String accessTokenSecret;
   String[] keyWords;
		
   public TwitterSampleSpout(String consumerKey, String consumerSecret,
      String accessToken, String accessTokenSecret, String[] keyWords) {
         this.consumerKey = consumerKey;
         this.consumerSecret = consumerSecret;
         this.accessToken = accessToken;
         this.accessTokenSecret = accessTokenSecret;
         this.keyWords = keyWords;
   }
		
   public TwitterSampleSpout() {
      // TODO Auto-generated constructor stub
   }
		
   @Override
   public void open(Map conf, TopologyContext context,
      SpoutOutputCollector collector) {
         queue = new LinkedBlockingQueue<Status>(1000);
         _collector = collector;
         StatusListener listener = new StatusListener() {
            @Override
            public void onStatus(Status status) {
               queue.offer(status);
            }
					
            @Override
            public void onDeletionNotice(StatusDeletionNotice sdn) {}
					
            @Override
            public void onTrackLimitationNotice(int i) {}
					
            @Override
            public void onScrubGeo(long l, long l1) {}
					
            @Override
            public void onException(Exception ex) {}
					
            @Override
            public void onStallWarning(StallWarning arg0) {
               // TODO Auto-generated method stub
            }
         };
				
         ConfigurationBuilder cb = new ConfigurationBuilder();
				
         cb.setDebugEnabled(true)
            .setOAuthConsumerKey(consumerKey)
            .setOAuthConsumerSecret(consumerSecret)
            .setOAuthAccessToken(accessToken)
            .setOAuthAccessTokenSecret(accessTokenSecret);
					
         _twitterStream = new TwitterStreamFactory(cb.build()).getInstance();
         _twitterStream.addListener(listener);
				
         if (keyWords.length == 0) {
            _twitterStream.sample();
         }else {
            FilterQuery query = new FilterQuery().track(keyWords);
            _twitterStream.filter(query);
         }
   }
			
   @Override
   public void nextTuple() {
      Status ret = queue.poll();
				
      if (ret == null) {
         Utils.sleep(50);
      } else {
         _collector.emit(new Values(ret));
      }
   }
			
   @Override
   public void close() {
      _twitterStream.shutdown();
   }
			
   @Override
   public Map<String, Object> getComponentConfiguration() {
      Config ret = new Config();
      ret.setMaxTaskParallelism(1);
      return ret;
   }
			
   @Override
   public void ack(Object id) {}
			
   @Override
   public void fail(Object id) {}
			
   @Override
   public void declareOutputFields(OutputFieldsDeclarer declarer) {
      declarer.declare(new Fields("tweet"));
   }
}

Hashtag閱讀器spout

由spout發(fā)出的tweet將被轉(zhuǎn)發(fā)到HashtagReaderBolt，它將處理該tweet并發(fā)出所有可用的hashtag。HashtagReaderBolt使用twitter4j提供的getHashTagEntities方法。getHashTagEntities讀取tweet并返回hashtag的列表。完整的程序代碼如下 -

編碼：HashtagReaderBolt.java

import java.util.HashMap;
import java.util.Map;

import twitter4j.*;
import twitter4j.conf.*;

import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;

import backtype.storm.task.OutputCollector;
import backtype.storm.task.TopologyContext;
import backtype.storm.topology.IRichBolt;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.tuple.Tuple;

public class HashtagReaderBolt implements IRichBolt {
   private OutputCollector collector;

   @Override
   public void prepare(Map conf, TopologyContext context, OutputCollector collector) {
      this.collector = collector;
   }

   @Override
   public void execute(Tuple tuple) {
      Status tweet = (Status) tuple.getValueByField("tweet");
      for(HashtagEntity hashtage : tweet.getHashtagEntities()) {
         System.out.println("Hashtag: " + hashtage.getText());
         this.collector.emit(new Values(hashtage.getText()));
      }
   }

   @Override
   public void cleanup() {}

   @Override
   public void declareOutputFields(OutputFieldsDeclarer declarer) {
      declarer.declare(new Fields("hashtag"));
   }
	
   @Override
   public Map<String, Object> getComponentConfiguration() {
      return null;
   }
	
}

Hashtag計(jì)數(shù)器spout

發(fā)出的hashtag將被轉(zhuǎn)發(fā)到HashtagCounterBolt。這個(gè)bolt將處理所有的hashtags，并使用Java Map對(duì)象將每個(gè)hashtags及其計(jì)數(shù)保存在內(nèi)存中。完整的程序代碼如下。

編碼：HashtagCounterBolt.java

import java.util.HashMap;
import java.util.Map;

import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;

import backtype.storm.task.OutputCollector;
import backtype.storm.task.TopologyContext;

import backtype.storm.topology.IRichBolt;
import backtype.storm.topology.OutputFieldsDeclarer;
import backtype.storm.tuple.Tuple;

public class HashtagCounterBolt implements IRichBolt {
   Map<String, Integer> counterMap;
   private OutputCollector collector;

   @Override
   public void prepare(Map conf, TopologyContext context, OutputCollector collector) {
      this.counterMap = new HashMap<String, Integer>();
      this.collector = collector;
   }

   @Override
   public void execute(Tuple tuple) {
      String key = tuple.getString(0);

      if(!counterMap.containsKey(key)){
         counterMap.put(key, 1);
      }else{
         Integer c = counterMap.get(key) + 1;
         counterMap.put(key, c);
      }
		
      collector.ack(tuple);
   }

   @Override
   public void cleanup() {
      for(Map.Entry<String, Integer> entry:counterMap.entrySet()){
         System.out.println("Result: " + entry.getKey()+" : " + entry.getValue());
      }
   }

   @Override
   public void declareOutputFields(OutputFieldsDeclarer declarer) {
      declarer.declare(new Fields("hashtag"));
   }
	
   @Override
   public Map<String, Object> getComponentConfiguration() {
      return null;
   }
	
}

提交拓?fù)?/h2>

提交拓?fù)涫侵饕獞?yīng)用程序。Twitter拓?fù)溆蒚witterSampleSpout，HashtagReaderBolt和HashtagCounterBolt組成。以下程序代碼顯示如何提交拓?fù)洹?/span>

編碼：TwitterHashtagStorm.java

import java.util.*;

import backtype.storm.tuple.Fields;
import backtype.storm.tuple.Values;
import backtype.storm.Config;
import backtype.storm.LocalCluster;
import backtype.storm.topology.TopologyBuilder;

public class TwitterHashtagStorm {
   public static void main(String[] args) throws Exception{
      String consumerKey = args[0];
      String consumerSecret = args[1];
		
      String accessToken = args[2];
      String accessTokenSecret = args[3];
		
      String[] arguments = args.clone();
      String[] keyWords = Arrays.copyOfRange(arguments, 4, arguments.length);
		
      Config config = new Config();
      config.setDebug(true);
		
      TopologyBuilder builder = new TopologyBuilder();
      builder.setSpout("twitter-spout", new TwitterSampleSpout(consumerKey,
         consumerSecret, accessToken, accessTokenSecret, keyWords));

      builder.setBolt("twitter-hashtag-reader-bolt", new HashtagReaderBolt())
         .shuffleGrouping("twitter-spout");

      builder.setBolt("twitter-hashtag-counter-bolt", new HashtagCounterBolt())
         .fieldsGrouping("twitter-hashtag-reader-bolt", new Fields("hashtag"));
			
      LocalCluster cluster = new LocalCluster();
      cluster.submitTopology("TwitterHashtagStorm", config,
         builder.createTopology());
      Thread.sleep(10000);
      cluster.shutdown();
   }
}

構(gòu)建和運(yùn)行應(yīng)用程序

完整的應(yīng)用程序有四個(gè)Java代碼。他們?nèi)缦?-

• TwitterSampleSpout.java
• HashtagReaderBolt.java
• HashtagCounterBolt.java
• TwitterHashtagStorm.java

您可以使用以下命令編譯應(yīng)用程序 -

javac -cp “/path/to/storm/apache-storm-0.9.5/lib/*”:”/path/to/twitter4j/lib/*” *.java

使用以下命令執(zhí)行應(yīng)用程序 -

javac -cp “/path/to/storm/apache-storm-0.9.5/lib/*”:”/path/to/twitter4j/lib/*”:.
TwitterHashtagStorm <customerkey> <customersecret> <accesstoken> <accesstokensecret>
<keyword1> <keyword2> … <keywordN>

輸出

應(yīng)用程序?qū)⒋蛴‘?dāng)前可用的主題標(biāo)簽及其計(jì)數(shù)。輸出應(yīng)類似于以下內(nèi)容 -

Result: jazztastic : 1
Result: foodie : 1
Result: Redskins : 1
Result: Recipe : 1
Result: cook : 1
Result: android : 1
Result: food : 2
Result: NoToxicHorseMeat : 1
Result: Purrs4Peace : 1
Result: livemusic : 1
Result: VIPremium : 1
Result: Frome : 1
Result: SundayRoast : 1
Result: Millennials : 1
Result: HealthWithKier : 1
Result: LPs30DaysofGratitude : 1
Result: cooking : 1
Result: gameinsight : 1
Result: Countryfile : 1
Result: androidgames : 1