Let us analyze a real time application to get the latest twitter feeds and its hashtags. Earlier, we have seen integration of Storm and Spark with Kafka. In both the scenarios, we created a Kafka Producer (using cli) to send message to the Kafka ecosystem. Then, the storm and spark inte-gration reads the messages by using the Kafka consumer and injects it into storm and spark ecosystem respectively. So, practically we need to create a Kafka Producer, which should −
Once the HashTags
are received by Kafka, the Storm / Spark integration receive the infor-mation and send it to Storm / Spark ecosystem.
The “Twitter Streaming API” can be accessed in any programming language. The “twitter4j” is an open source, unofficial Java library, which provides a Java based module to easily access the “Twitter Streaming API”. The “twitter4j” provides a listener based framework to access the tweets. To access the “Twitter Streaming API”, we need to sign in for Twitter developer account and should get the following OAuth authentication details.
Once the developer account is created, download the “twitter4j” jar files and place it in the java class path.
The Complete Twitter Kafka producer coding (KafkaTwitterProducer.java) is listed below −
import java.util.Arrays; import java.util.Properties; import java.util.concurrent.LinkedBlockingQueue; import twitter4j.*; import twitter4j.conf.*; import org.apache.kafka.clients.producer.Producer; import org.apache.kafka.clients.producer.KafkaProducer; import org.apache.kafka.clients.producer.ProducerRecord; public class KafkaTwitterProducer { public static void main(String[] args) throws Exception { LinkedBlockingQueue<Status> queue = new LinkedBlockingQueue<Sta-tus>(1000); if(args.length < 5){ System.out.println( "Usage: KafkaTwitterProducer <twitter-consumer-key> <twitter-consumer-secret> <twitter-access-token> <twitter-access-token-secret> <topic-name> <twitter-search-keywords>"); return; } String consumerKey = args[0].toString(); String consumerSecret = args[1].toString(); String accessToken = args[2].toString(); String accessTokenSecret = args[3].toString(); String topicName = args[4].toString(); String[] arguments = args.clone(); String[] keyWords = Arrays.copyOfRange(arguments, 5, arguments.length); ConfigurationBuilder cb = new ConfigurationBuilder(); cb.setDebugEnabled(true) .setOAuthConsumerKey(consumerKey) .setOAuthConsumerSecret(consumerSecret) .setOAuthAccessToken(accessToken) .setOAuthAccessTokenSecret(accessTokenSecret); TwitterStream twitterStream = new TwitterStreamFactory(cb.build()).get-Instance(); StatusListener listener = new StatusListener() { @Override public void onStatus(Status status) { queue.offer(status); // System.out.println("@" + status.getUser().getScreenName() + " - " + status.getText()); // System.out.println("@" + status.getUser().getScreen-Name()); /*for(URLEntity urle : status.getURLEntities()) { System.out.println(urle.getDisplayURL()); }*/ /*for(HashtagEntity hashtage : status.getHashtagEntities()) { System.out.println(hashtage.getText()); }*/ } @Override public void onDeletionNotice(StatusDeletionNotice statusDeletion-Notice) { // System.out.println("Got a status deletion notice id:" + statusDeletionNotice.getStatusId()); } @Override public void onTrackLimitationNotice(int numberOfLimitedStatuses) { // System.out.println("Got track limitation notice:" + num-berOfLimitedStatuses); } @Override public void onScrubGeo(long userId, long upToStatusId) { // System.out.println("Got scrub_geo event userId:" + userId + "upToStatusId:" + upToStatusId); } @Override public void onStallWarning(StallWarning warning) { // System.out.println("Got stall warning:" + warning); } @Override public void onException(Exception ex) { ex.printStackTrace(); } }; twitterStream.addListener(listener); FilterQuery query = new FilterQuery().track(keyWords); twitterStream.filter(query); Thread.sleep(5000); //Add Kafka producer config settings Properties props = new Properties(); props.put("bootstrap.servers", "localhost:9092"); props.put("acks", "all"); props.put("retries", 0); props.put("batch.size", 16384); props.put("linger.ms", 1); props.put("buffer.memory", 33554432); props.put("key.serializer", "org.apache.kafka.common.serializa-tion.StringSerializer"); props.put("value.serializer", "org.apache.kafka.common.serializa-tion.StringSerializer"); Producer<String, String> producer = new KafkaProducer<String, String>(props); int i = 0; int j = 0; while(i < 10) { Status ret = queue.poll(); if (ret == null) { Thread.sleep(100); i++; }else { for(HashtagEntity hashtage : ret.getHashtagEntities()) { System.out.println("Hashtag: " + hashtage.getText()); producer.send(new ProducerRecord<String, String>( top-icName, Integer.toString(j++), hashtage.getText())); } } } producer.close(); Thread.sleep(5000); twitterStream.shutdown(); } }
Compile the application using the following command −
javac -cp “/path/to/kafka/libs/*”:”/path/to/twitter4j/lib/*”:. KafkaTwitterProducer.java
Open two consoles. Run the above compiled application as shown below in one console.
java -cp “/path/to/kafka/libs/*”:”/path/to/twitter4j/lib/*”: . KafkaTwitterProducer <twitter-consumer-key> <twitter-consumer-secret> <twitter-access-token> <twitter-ac-cess-token-secret> my-first-topic food
Run any one of the Spark / Storm application explained in the previous chapter in another win-dow. The main point to note is that the topic used should be same in both cases. Here, we have used “my-first-topic” as the topic name.
The output of this application will depend on the keywords and the current feed of the twitter. A sample output is specified below (storm integration).
. . . food : 1 foodie : 2 burger : 1 . . .