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diff --git a/event-client-kafka/src/main/java/org/onap/aai/event/client/KafkaEventConsumer.java b/event-client-kafka/src/main/java/org/onap/aai/event/client/KafkaEventConsumer.java
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+/**
+ * ============LICENSE_START=======================================================
+ * org.onap.aai
+ * ================================================================================
+ * Copyright © 2017 AT&T Intellectual Property. All rights reserved.
+ * Copyright © 2017 European Software Marketing Ltd.
+ * ================================================================================
+ * Licensed 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.
+ * ============LICENSE_END=========================================================
+ *
+ * ECOMP is a trademark and service mark of AT&T Intellectual Property.
+ */
+package org.onap.aai.event.client;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Properties;
+import org.apache.kafka.clients.consumer.ConsumerConfig;
+import org.apache.kafka.clients.consumer.ConsumerRecord;
+import org.apache.kafka.clients.consumer.ConsumerRecords;
+import org.apache.kafka.clients.consumer.KafkaConsumer;
+import org.apache.kafka.clients.consumer.OffsetAndMetadata;
+import org.apache.kafka.common.TopicPartition;
+import org.apache.kafka.common.serialization.StringDeserializer;
+import org.onap.aai.cl.api.Logger;
+import org.onap.aai.cl.eelf.LoggerFactory;
+import org.onap.aai.event.api.EventConsumer;
+import org.onap.aai.event.api.MessageWithOffset;
+
+/**
+ * Event Bus Client consumer API for Kafka Implementation .Its a wrapper around KafkaConsumer which is NOT thread safe.
+ * The KafkaConsumer maintains TCP connections to the necessary brokers to fetch data. Failure to close the consumer
+ * after use will leak these connections Ref : https://kafka.apache.org/0102/javadoc/org/apache/kafka/clients/consumer/
+ * KafkaConsumer.html
+ *
+ */
+public class KafkaEventConsumer implements EventConsumer {
+
+ private static Logger log = LoggerFactory.getInstance().getLogger(KafkaEventConsumer.class);
+
+ public interface KafkaConsumerFactory {
+ public KafkaConsumer<String, String> createConsumer(Properties props);
+ }
+
+ private static KafkaConsumerFactory consumerFactory = KafkaConsumer::new;
+
+ private final KafkaConsumer<String, String> consumer;
+
+ /**
+ * Replace the consumer factory (intended to be used for testing purposes only).
+ *
+ * @param consumerFactory
+ */
+ static void setConsumerFactory(KafkaConsumerFactory consumerFactory) {
+ KafkaEventConsumer.consumerFactory = consumerFactory;
+ }
+
+ /**
+ *
+ * @param hosts - A list of host/port pairs to use for establishing the initial connection to the Kafka cluster. The
+ * client will make use of all servers irrespective of which servers are specified here for
+ * bootstrapping—this list only impacts the initial hosts used to discover the full set of servers. This list
+ * should be in the form host1:port1,host2:port2,....
+ * @param topic - Topic to consume the messages from
+ * @param groupId - A unique string that identifies the consumer group this consumer belongs to
+ */
+ public KafkaEventConsumer(String hosts, String topic, String groupId) {
+ Properties props = new Properties();
+ props.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, hosts);
+ props.put(ConsumerConfig.GROUP_ID_CONFIG, groupId);
+
+ // Set this property, if auto commit should happen.
+ props.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, "false");
+
+ props.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
+ props.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class.getName());
+ consumer = consumerFactory.createConsumer(props);
+ consumer.subscribe(Arrays.asList(topic));
+ }
+
+ public void close() {
+ consumer.close();
+ }
+
+ /**
+ *
+ */
+ @Override
+ public Iterable<String> consume() throws Exception {
+ log.debug("Querying Kafka for messages");
+ ConsumerRecords<String, String> records = consumer.poll(0);
+ List<String> list = new ArrayList<>();
+ for (ConsumerRecord<String, String> record : records) {
+ list.add(record.value());
+ }
+ return list;
+
+ }
+
+ @Override
+ public Iterable<MessageWithOffset> consumeWithOffsets() throws Exception {
+ log.debug("Querying Kafka for messages");
+ ConsumerRecords<String, String> records = consumer.poll(0);
+ List<MessageWithOffset> list = new ArrayList<>();
+ for (ConsumerRecord<String, String> record : records) {
+ list.add(new MessageWithOffset(record.offset(), record.value()));
+ }
+ return list;
+ }
+
+ @Override
+ public Iterable<String> consumeAndCommit() throws Exception {
+ Iterable<String> result = consume();
+ consumer.commitSync();
+ return result;
+ }
+
+ @Override
+ public void commitOffsets() throws Exception {
+ consumer.commitSync();
+ }
+
+ @Override
+ public void commitOffsets(long offset) throws Exception {
+ Map<TopicPartition, OffsetAndMetadata> offsetsMap = new HashMap<>();
+ offsetsMap.put(consumer.assignment().iterator().next(), new OffsetAndMetadata(offset));
+ consumer.commitSync(offsetsMap);
+ }
+
+}