Kafka app that listens to events from applications and pushes them to a kafka bus

Change-Id: I8026f13f10aa00f6389b89459fa8ebd74de289a3
diff --git a/src/main/java/org/opencord/kafka/impl/KafkaConfig.java b/src/main/java/org/opencord/kafka/impl/KafkaConfig.java
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+/*
+ * Copyright 2018-present Open Networking 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.
+ */
+
+package org.opencord.kafka.impl;
+
+import org.onosproject.core.ApplicationId;
+import org.onosproject.net.config.Config;
+
+/**
+ * Configuration of the Kafka publishing endpoint.
+ */
+public class KafkaConfig extends Config<ApplicationId> {
+
+    private static final String BOOTSTRAP_SERVERS = "bootstrapServers";
+    private static final String RETRIES = "retries";
+    private static final String RECONNECT_BACKOFF = "reconnectBackoff";
+    private static final String INFLIGHT_REQUESTS = "inflightRequests";
+    private static final String ACKS = "acks";
+
+    private static final String DEFAULT_RETRIES = "1";
+    private static final String DEFAULT_RECONNECT_BACKOFF = "500";
+    private static final String DEFAULT_INFLIGHT_REQUESTS = "5";
+    private static final String DEFAULT_ACKS = "1";
+
+    @Override
+    public boolean isValid() {
+        return hasOnlyFields(BOOTSTRAP_SERVERS, RETRIES, RECONNECT_BACKOFF,
+                INFLIGHT_REQUESTS, ACKS) && hasFields(BOOTSTRAP_SERVERS);
+    }
+
+    /**
+     * Returns the Kafka bootstrap servers.
+     * <p>
+     * This can be a hostname/IP and port (e.g. 10.1.1.1:9092).
+     * </p>
+     *
+     * @return Kafka bootstrap servers
+     */
+    public String getBootstrapServers() {
+        return object.path(BOOTSTRAP_SERVERS).asText();
+    }
+
+    /**
+     * Returns the number of retries.
+     *
+     * @return retries
+     */
+    public String getRetries() {
+        return get(RETRIES, DEFAULT_RETRIES);
+    }
+
+    /**
+     * Returns the reconnect backoff in milliseconds.
+     *
+     * @return reconnect backoff
+     */
+    public String getReconnectBackoff() {
+        return get(RECONNECT_BACKOFF, DEFAULT_RECONNECT_BACKOFF);
+    }
+
+    /**
+     * Returns the number of inflight requests.
+     *
+     * @return inflight requests
+     */
+    public String getInflightRequests() {
+        return get(INFLIGHT_REQUESTS, DEFAULT_INFLIGHT_REQUESTS);
+    }
+
+    /**
+     * Returns the number of acks.
+     *
+     * @return acks
+     */
+    public String getAcks() {
+        return get(ACKS, DEFAULT_ACKS);
+    }
+}