1 files changed, 67 insertions, 0 deletions
diff --git a/event-client-api/src/main/java/org/onap/aai/event/api/EventConsumer.java b/event-client-api/src/main/java/org/onap/aai/event/api/EventConsumer.java
new file mode 100644
index 0000000..95effaf
--- /dev/null
+++ b/event-client-api/src/main/java/org/onap/aai/event/api/EventConsumer.java
@@ -0,0 +1,67 @@
+/**
+ * ============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.api;
+
+public interface EventConsumer {
+
+    /**
+     * Fetches any relevant messages currently on the Event Bus, according to the configuration and manages the offsets
+     * for the client.
+     *
+     * @return List of messages fetched from the Event Bus.
+     * @throws Exception
+     */
+    public Iterable<String> consumeAndCommit() throws Exception;
+
+
+    /**
+     * Fetches any relevant messages currently on the Event Bus, according to the configuration and expects the client
+     * to explicitly call the {@link #commitOffsets()} in order to commit the offsets
+     *
+     * @return List of messages fetched from the Event Bus.
+     * @throws Exception
+     */
+    public Iterable<String> consume() throws Exception;
+
+    /**
+     * Fetches any relevant messages currently on the Event Bus with their offsets, according to the configuration and
+     * expects the client to explicitly call the {@link #commitOffsets()} in order to commit the offsets
+     *
+     * @throws Exception
+     */
+    public Iterable<MessageWithOffset> consumeWithOffsets() throws Exception;
+
+    /**
+     * Commits the offsets of the previously consumed messages from the Event Bus
+     *
+     * @throws Exception if the offsets could not be committed
+     */
+    public void commitOffsets() throws Exception;
+
+    /**
+     * Commits the offsets of messages consumed up to offset
+     *
+     * @throws Exception if the offsets could not be committed
+     */
+    public void commitOffsets(long offset) throws Exception;
+}