Intial Stub code for the Cluster features in Kafka Application.(patchset #4)
Stub Implementation of KafkaStorage Service.
Change-Id: Iad929a8f1b13149583c9526b41e8f1a3a829fa1e
diff --git a/apps/kafka-integration/api/src/main/java/org/onosproject/kafkaintegration/api/KafkaEventStorageService.java b/apps/kafka-integration/api/src/main/java/org/onosproject/kafkaintegration/api/KafkaEventStorageService.java
new file mode 100644
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--- /dev/null
+++ b/apps/kafka-integration/api/src/main/java/org/onosproject/kafkaintegration/api/KafkaEventStorageService.java
@@ -0,0 +1,40 @@
+/**
+ * Copyright 2016 Open Networking Laboratory
+ * 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.
+ */
+package org.onosproject.kafkaintegration.api;
+
+import org.onosproject.kafkaintegration.api.dto.OnosEvent;
+
+/**
+ * APIs to insert and delete into a local store. This store is used to keep
+ * track of events that are being published.
+ */
+public interface KafkaEventStorageService {
+
+ /**
+ * Inserts the Generated event into the local cache.
+ *
+ * @param e the ONOS Event
+ * @return true if the insertion was successful
+ */
+ boolean insertCacheEntry(OnosEvent e);
+
+ /**
+ * Updates the counter with the most recently published event's sequence
+ * number.
+ *
+ * @param sequenceNumber the updated value of sequence number.
+ */
+ void updateLastPublishedEntry(Long sequenceNumber);
+}
diff --git a/apps/kafka-integration/app/src/main/java/org/onosproject/kafkaintegration/impl/KafkaStorageManager.java b/apps/kafka-integration/app/src/main/java/org/onosproject/kafkaintegration/impl/KafkaStorageManager.java
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+++ b/apps/kafka-integration/app/src/main/java/org/onosproject/kafkaintegration/impl/KafkaStorageManager.java
@@ -0,0 +1,108 @@
+/**
+ * Copyright 2016 Open Networking Laboratory
+ * 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.
+ */
+package org.onosproject.kafkaintegration.impl;
+
+import java.util.TreeMap;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onosproject.kafkaintegration.api.KafkaEventStorageService;
+import org.onosproject.kafkaintegration.api.dto.OnosEvent;
+import org.onosproject.store.service.AtomicValue;
+import org.onosproject.store.service.StorageService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+@Component(immediate = true)
+public class KafkaStorageManager implements KafkaEventStorageService {
+
+ @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+ protected StorageService storageService;
+
+ private TreeMap<Long, OnosEvent> kafkaEventStore;
+
+ private AtomicValue<Long> lastPublishedEvent;
+
+ private final Logger log = LoggerFactory.getLogger(getClass());
+
+ private ScheduledExecutorService gcExService;
+
+ private InternalGarbageCollector gcTask;
+
+ // Thread scheduler parameters.
+ private final long delay = 0;
+ private final long period = 1;
+
+ @Activate
+ protected void activate() {
+ kafkaEventStore = new TreeMap<Long, OnosEvent>();
+ lastPublishedEvent = storageService.<Long>atomicValueBuilder()
+ .withName("onos-app-kafka-published-seqNumber").build()
+ .asAtomicValue();
+
+ startGC();
+
+ log.info("Started");
+ }
+
+ private void startGC() {
+ log.info("Starting Garbage Collection Service");
+ gcExService = Executors.newSingleThreadScheduledExecutor();
+ gcTask = new InternalGarbageCollector();
+ gcExService.scheduleAtFixedRate(gcTask, delay, period,
+ TimeUnit.SECONDS);
+ }
+
+ @Deactivate
+ protected void deactivate() {
+ stopGC();
+ log.info("Stopped");
+ }
+
+ private void stopGC() {
+ log.info("Stopping Garbage Collection Service");
+ gcExService.shutdown();
+ }
+
+ @Override
+ public boolean insertCacheEntry(OnosEvent e) {
+ // TODO: Fill in the code once the event carries timestamp info.
+ return true;
+ }
+
+ @Override
+ public void updateLastPublishedEntry(Long sequenceNumber) {
+ this.lastPublishedEvent.set(sequenceNumber);
+ }
+
+ /**
+ * Removes events from the Kafka Event Store which have been published.
+ *
+ */
+ private class InternalGarbageCollector implements Runnable {
+
+ @Override
+ public void run() {
+ kafkaEventStore.headMap(lastPublishedEvent.get(), true).clear();
+ }
+ }
+
+}