X-Git-Url: https://gerrit.o-ran-sc.org/r/gitweb?a=blobdiff_plain;f=datafilecollector%2Fsrc%2Fmain%2Fjava%2Forg%2Foran%2Fdatafile%2Ftasks%2FKafkaTopicListener.java;fp=datafilecollector%2Fsrc%2Fmain%2Fjava%2Forg%2Foran%2Fdatafile%2Ftasks%2FKafkaTopicListener.java;h=b67eb044513bcd890330a6e263be895114ea7dc5;hb=f0af18429aec79a590835103fedd753ee5ea93a9;hp=0000000000000000000000000000000000000000;hpb=54c8fecebbb5e19010e56eddf3aba8e127e0abc3;p=nonrtric%2Fplt%2Franpm.git

diff --git a/datafilecollector/src/main/java/org/oran/datafile/tasks/KafkaTopicListener.java b/datafilecollector/src/main/java/org/oran/datafile/tasks/KafkaTopicListener.java
new file mode 100644
index 0000000..b67eb04
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+++ b/datafilecollector/src/main/java/org/oran/datafile/tasks/KafkaTopicListener.java
@@ -0,0 +1,106 @@
+/*-
+ * ========================LICENSE_START=================================
+ * O-RAN-SC
+ * %%
+ * Copyright (C) 2021 Nordix Foundation
+ * %%
+ * 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===================================
+ */
+
+package org.oran.datafile.tasks;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
+import lombok.ToString;
+
+import org.apache.kafka.clients.consumer.ConsumerConfig;
+import org.apache.kafka.common.serialization.StringDeserializer;
+import org.oran.datafile.configuration.AppConfig;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import reactor.core.publisher.Flux;
+import reactor.kafka.receiver.KafkaReceiver;
+import reactor.kafka.receiver.ReceiverOptions;
+
+/**
+ * The class streams incoming requests from a Kafka topic and sends them further
+ * to a multi cast sink, which several other streams can connect to.
+ */
+@SuppressWarnings("squid:S2629") // Invoke method(s) only conditionally
+public class KafkaTopicListener {
+
+    @ToString
+    public static class DataFromTopic {
+        public final String key;
+        public final String value;
+
+        public DataFromTopic(String key, String value) {
+            this.key = key;
+            this.value = value;
+        }
+    }
+
+    private static final Logger logger = LoggerFactory.getLogger(KafkaTopicListener.class);
+
+    private Flux<DataFromTopic> dataFromTopic;
+    private final AppConfig appConfig;
+
+    public KafkaTopicListener(AppConfig applConfig) {
+        this.appConfig = applConfig;
+    }
+
+    public Flux<DataFromTopic> getFlux() {
+        if (this.dataFromTopic == null) {
+            this.dataFromTopic = startReceiveFromTopic();
+        }
+        return this.dataFromTopic;
+    }
+
+    private Flux<DataFromTopic> startReceiveFromTopic() {
+        logger.debug("Listening to kafka topic: {}, client id: {}", appConfig.getInputTopic(),
+            appConfig.getKafkaClientId());
+        return KafkaReceiver.create(kafkaInputProperties()) //
+            .receive() //
+            .doOnNext(
+                input -> logger.debug("Received from kafka topic: {} :{}", appConfig.getInputTopic(), input.value())) //
+            .doOnError(t -> logger.error("KafkaTopicReceiver error: {}", t.getMessage())) //
+            .doFinally(sig -> logger.error("KafkaTopicReceiver stopped, reason: {}", sig)) //
+            .doFinally(sig -> this.dataFromTopic = null) //
+            .filter(t -> !t.value().isEmpty() || !t.key().isEmpty()) //
+            .map(input -> new DataFromTopic(input.key(), input.value())) //
+            .publish() //
+            .autoConnect();
+    }
+
+    private ReceiverOptions<String, String> kafkaInputProperties() {
+        Map<String, Object> consumerProps = new HashMap<>();
+        if (appConfig.getKafkaBootStrapServers().isEmpty()) {
+            logger.error("No kafka boostrap server is setup");
+        }
+        consumerProps.put(ConsumerConfig.BOOTSTRAP_SERVERS_CONFIG, appConfig.getKafkaBootStrapServers());
+        consumerProps.put(ConsumerConfig.GROUP_ID_CONFIG, "osc-dmaap-adapter-" + appConfig.getInputTopic());
+        consumerProps.put(ConsumerConfig.KEY_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
+        consumerProps.put(ConsumerConfig.VALUE_DESERIALIZER_CLASS_CONFIG, StringDeserializer.class);
+        consumerProps.put(ConsumerConfig.ENABLE_AUTO_COMMIT_CONFIG, true);
+        consumerProps.put(ConsumerConfig.CLIENT_ID_CONFIG, appConfig.getKafkaClientId());
+        this.appConfig.addKafkaSecurityProps(consumerProps);
+
+        return ReceiverOptions.<String, String>create(consumerProps)
+            .subscription(Collections.singleton(appConfig.getInputTopic()));
+    }
+
+}