Java examples for Big Data:apache kafka
Kafka To Cassandra using apache beam
/*// ww w. j a va2 s. c om * 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.beam.samples.unbounded; import org.apache.beam.sdk.Pipeline; import org.apache.beam.sdk.coders.StringUtf8Coder; import org.apache.beam.sdk.coders.VoidCoder; //import org.apache.beam.sdk.io.cassandra.CassandraIO; import org.apache.beam.sdk.io.jms.JmsIO; import org.apache.beam.sdk.io.kafka.KafkaIO; import org.apache.beam.sdk.io.kafka.KafkaRecord; import org.apache.beam.sdk.io.mongodb.MongoDbIO; import org.apache.beam.sdk.options.*; import org.apache.beam.sdk.transforms.*; import org.apache.beam.sdk.values.KV; import org.apache.beam.sdk.values.PCollection; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.text.SimpleDateFormat; import java.util.Arrays; import java.util.Date; public class KafkaToCassandra { private static final Logger LOG = LoggerFactory .getLogger(KafkaToCassandra.class); /** * Specific pipeline options. */ private interface Options extends PipelineOptions { String GDELT_EVENTS_URL = "http://data.gdeltproject.org/events/"; @Description("GDELT file date") @Default.InstanceFactory(GDELTFileFactory.class) String getDate(); void setDate(String value); @Description("Input Path") String getInput(); void setInput(String value); @Description("Kafka Bootstrap Servers") @Default.String("localhost:9092") String getKafkaServer(); void setKafkaServer(String value); @Description("Kafka Topic Name") @Default.String("gdelt") String getKafkaTopic(); void setKafkaTopic(String value); class GDELTFileFactory implements DefaultValueFactory<String> { public String create(PipelineOptions options) { SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd"); return format.format(new Date()); } } } private static String getCountry(String row) { String[] fields = row.split("\\t+"); if (fields.length > 22) { if (fields[21].length() > 2) { return fields[21].substring(0, 1); } return fields[21]; } return "NA"; } public static void main(String[] args) throws Exception { Options options = PipelineOptionsFactory.fromArgs(args) .withValidation().as(Options.class); if (options.getInput() == null) { options.setInput(Options.GDELT_EVENTS_URL + options.getDate() + ".export.CSV.zip"); } LOG.info(options.toString()); Pipeline pipeline = Pipeline.create(options); // now we connect to the queue and process every event PCollection<String> data = pipeline.apply( "ReadFromKafka", KafkaIO.read() .withBootstrapServers(options.getKafkaServer()) .withTopics(Arrays.asList(options.getKafkaTopic())) .withKeyCoder(StringUtf8Coder.of()) .withValueCoder(StringUtf8Coder.of())).apply( "ExtractPayload", ParDo.of(new DoFn<KafkaRecord, String>() { @ProcessElement public void processElement(ProcessContext c) throws Exception { c.output(c.element().getKV().getValue().toString()); } })); // We filter the events for a given country (IN=India) and send them to their own Topic final String country = "IN"; PCollection<String> eventsInIndia = data.apply("FilterByCountry", Filter.by(new SerializableFunction<String, Boolean>() { public Boolean apply(String row) { return getCountry(row).equals(country); } })); PCollection<KV<String, String>> eventsInIndiaKV = eventsInIndia .apply("ExtractPayload", ParDo.of(new DoFn<String, KV<String, String>>() { @ProcessElement public void processElement(ProcessContext c) throws Exception { c.output(KV.of("india", c.element())); } })); //TODO: Test write eventsInIndiaKV.apply( "WriteToKafka", KafkaIO.write() .withBootstrapServers(options.getKafkaServer()) .withTopic("india") // .withKeyCoder(VoidCoder.of()) .withKeyCoder(StringUtf8Coder.of()) .withValueCoder(StringUtf8Coder.of())); // TODO: fix error on grouping without windows // we count the events per country and register them in Mongo PCollection<String> countByCountry = data .apply("ExtractLocation", ParDo.of(new DoFn<String, String>() { @ProcessElement public void processElement(ProcessContext c) { c.output(getCountry(c.element())); } })) .apply("FilterValidLocations", Filter.by(new SerializableFunction<String, Boolean>() { public Boolean apply(String input) { return (!input.equals("NA") && !input.startsWith("-") && input .length() == 2); } })) .apply("CountByLocation", Count.<String> perElement()) .apply("ConvertToJson", MapElements .via(new SimpleFunction<KV<String, Long>, String>() { public String apply( KV<String, Long> input) { return "{\"" + input.getKey() + "\": " + input.getValue() + "}"; } })); //TODO Finish once CassandraIO is merged // countByCountry // .apply("ToCassandraRow", ParDo.of(new DoFn<String, CassandraRow>() { // @ProcessElement // public void processElement(ProcessContext c) { // CassandraRow row = new CassandraRow(); // row.add("name", CassandraColumnDefinition.Type.TEXT, c.element()); // c.output(row); // } // })) // .apply("WriteToCassandra", // CassandraIO.write() // .withHosts(new String[] {"localhost"}) // .withKeyspace("gdelt") //// .withTable("percountry") //// .withConfig(new HashMap<String, String>()) //// .withColumns("ab") // ); pipeline.run(); } }