Publish and Subscribe to Kafka topic

Issue-ID: POLICY-4134
Signed-off-by: Sirisha_Manchikanti <sirisha.manchikanti@est.tech>
Change-Id: Idefa5b6f3cb702a4b478b76570717e73214d235a

1 files changed, 47 insertions, 12 deletions

diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/BusPublisher.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/BusPublisher.java
index e0df7095..fe9bab23 100644
--- a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/BusPublisher.java
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/BusPublisher.java
@@ -32,13 +32,14 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
-import java.util.Random;
+import java.util.UUID;
 import java.util.concurrent.TimeUnit;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.kafka.clients.consumer.ConsumerConfig;
 import org.apache.kafka.clients.producer.KafkaProducer;
+import org.apache.kafka.clients.producer.Producer;
 import org.apache.kafka.clients.producer.ProducerConfig;
 import org.apache.kafka.clients.producer.ProducerRecord;
-import org.apache.kafka.common.record.CompressionType;
 import org.onap.dmaap.mr.client.impl.MRSimplerBatchPublisher;
 import org.onap.dmaap.mr.client.response.MRPublisherResponse;
 import org.onap.dmaap.mr.test.clients.ProtocolTypeConstants;
@@ -155,22 +156,45 @@ public interface BusPublisher {
     public static class KafkaPublisherWrapper implements BusPublisher {
 
         private static Logger logger = LoggerFactory.getLogger(KafkaPublisherWrapper.class);
+        private static final String KEY_SERIALIZER = "org.apache.kafka.common.serialization.StringSerializer";
+
+        private String topic;
 
         /**
-         * The actual Kafka publisher.
+         * Kafka publisher.
          */
-        private final KafkaProducer producer;
+        private Producer<String, String> producer;
+        protected Properties kafkaProps;
 
         /**
-         * Constructor.
+         * Kafka Publisher Wrapper.
          *
          * @param busTopicParams topic parameters
          */
-        public KafkaPublisherWrapper(BusTopicParams busTopicParams) {
-            // TODO Setting of topic parameters is not implemented yet.
-            //Setup Properties for Kafka Producer
-            Properties kafkaProps = new Properties();
-            this.producer = new KafkaProducer(kafkaProps);
+        protected KafkaPublisherWrapper(BusTopicParams busTopicParams) {
+
+            if (busTopicParams.isTopicInvalid()) {
+                throw new IllegalArgumentException("No topic for Kafka");
+            }
+
+            this.topic = busTopicParams.getTopic();
+
+            //Setup Properties for consumer
+            kafkaProps = new Properties();
+            kafkaProps.setProperty(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, busTopicParams.getServers().get(0));
+            if (busTopicParams.isAdditionalPropsValid()) {
+                for (Map.Entry<String, String> entry : busTopicParams.getAdditionalProps().entrySet()) {
+                    kafkaProps.put(entry.getKey(), entry.getValue());
+                }
+            }
+            if (kafkaProps.get(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG) == null) {
+                kafkaProps.setProperty(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, KEY_SERIALIZER);
+            }
+            if (kafkaProps.get(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG) == null) {
+                kafkaProps.setProperty(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, KEY_SERIALIZER);
+            }
+
+            producer = new KafkaProducer<>(kafkaProps);
         }
 
         @Override
@@ -178,7 +202,18 @@ public interface BusPublisher {
             if (message == null) {
                 throw new IllegalArgumentException("No message provided");
             }
-            // TODO Sending messages is not implemented yet
+
+            try {
+                //Create the record
+                ProducerRecord<String, String> record = new ProducerRecord<String, String>(topic,
+                    UUID.randomUUID().toString(), message);
+
+                this.producer.send(record);
+                producer.flush();
+            } catch (Exception e) {
+                logger.warn("{}: SEND of {} cannot be performed because of {}", this, message, e.getMessage(), e);
+                return false;
+            }
             return true;
         }
 
@@ -186,7 +221,7 @@ public interface BusPublisher {
         public void close() {
             logger.info("{}: CLOSE", this);
 
-            try (this.producer) {
+            try {
                 this.producer.close();
             } catch (Exception e) {
                 logger.warn("{}: CLOSE FAILED because of {}", this, e.getMessage(), e);