1 files changed, 210 insertions, 0 deletions
diff --git a/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/impl/CambriaConsumerWrapper.java b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/impl/CambriaConsumerWrapper.java
new file mode 100644
index 00000000..fedde284
--- /dev/null
+++ b/policy-endpoints/src/main/java/org/onap/policy/common/endpoints/event/comm/bus/internal/impl/CambriaConsumerWrapper.java
@@ -0,0 +1,210 @@
+/*
+ * ============LICENSE_START=======================================================
+ * policy-endpoints
+ * ================================================================================
+ * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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.onap.policy.common.endpoints.event.comm.bus.internal.impl;
+
+import com.att.nsa.cambria.client.CambriaClientBuilders;
+import com.att.nsa.cambria.client.CambriaClientBuilders.ConsumerBuilder;
+import com.att.nsa.cambria.client.CambriaConsumer;
+
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.security.GeneralSecurityException;
+import java.util.List;
+
+import org.onap.policy.common.endpoints.event.comm.bus.internal.FilterableBusConsumer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Cambria based consumer
+ */
+public class CambriaConsumerWrapper implements FilterableBusConsumer {
+
+    /**
+     * logger
+     */
+    private static Logger logger = LoggerFactory.getLogger(CambriaConsumerWrapper.class);
+
+    /**
+     * Used to build the consumer.
+     */
+    private final ConsumerBuilder builder;
+
+    /**
+     * Locked while updating {@link #consumer} and {@link #newConsumer}.
+     */
+    private final Object consLocker = new Object();
+
+    /**
+     * Cambria client
+     */
+    private CambriaConsumer consumer;
+
+    /**
+     * Cambria client to use for next fetch
+     */
+    private CambriaConsumer newConsumer = null;
+
+    /**
+     * fetch timeout
+     */
+    protected int fetchTimeout;
+
+    /**
+     * close condition
+     */
+    protected Object closeCondition = new Object();
+
+    /**
+     * Cambria Consumer Wrapper
+     *
+     * @param servers messaging bus hosts
+     * @param topic topic
+     * @param apiKey API Key
+     * @param apiSecret API Secret
+     * @param consumerGroup Consumer Group
+     * @param consumerInstance Consumer Instance
+     * @param fetchTimeout Fetch Timeout
+     * @param fetchLimit Fetch Limit
+     * @throws GeneralSecurityException
+     * @throws MalformedURLException
+     */
+    public CambriaConsumerWrapper(List<String> servers, String topic, String apiKey, String apiSecret,
+            String consumerGroup, String consumerInstance, int fetchTimeout, int fetchLimit, boolean useHttps,
+            boolean useSelfSignedCerts) {
+        this(servers, topic, apiKey, apiSecret, null, null, consumerGroup, consumerInstance, fetchTimeout, fetchLimit,
+                useHttps, useSelfSignedCerts);
+    }
+
+    public CambriaConsumerWrapper(List<String> servers, String topic, String apiKey, String apiSecret, String username,
+            String password, String consumerGroup, String consumerInstance, int fetchTimeout, int fetchLimit,
+            boolean useHttps, boolean useSelfSignedCerts) {
+
+        this.fetchTimeout = fetchTimeout;
+
+        this.builder = new CambriaClientBuilders.ConsumerBuilder();
+
+        builder.knownAs(consumerGroup, consumerInstance).usingHosts(servers).onTopic(topic).waitAtServer(fetchTimeout)
+                .receivingAtMost(fetchLimit);
+
+        // Set read timeout to fetch timeout + 30 seconds (TBD: this should be configurable)
+        builder.withSocketTimeout(fetchTimeout + 30000);
+
+        if (useHttps) {
+            builder.usingHttps();
+
+            if (useSelfSignedCerts) {
+                builder.allowSelfSignedCertificates();
+            }
+        }
+
+        if (apiKey != null && !apiKey.isEmpty() && apiSecret != null && !apiSecret.isEmpty()) {
+            builder.authenticatedBy(apiKey, apiSecret);
+        }
+
+        if (username != null && !username.isEmpty() && password != null && !password.isEmpty()) {
+            builder.authenticatedByHttp(username, password);
+        }
+
+        try {
+            this.consumer = builder.build();
+        } catch (MalformedURLException | GeneralSecurityException e) {
+            throw new IllegalArgumentException(e);
+        }
+    }
+
+    @Override
+    public Iterable<String> fetch() throws IOException, InterruptedException {
+        try {
+            return getCurrentConsumer().fetch();
+        } catch (final IOException e) {
+            logger.error("{}: cannot fetch because of {} - backoff for {} ms.", this, e.getMessage(),
+                    this.fetchTimeout);
+            synchronized (this.closeCondition) {
+                this.closeCondition.wait(this.fetchTimeout);
+            }
+
+            throw e;
+        }
+    }
+
+    @Override
+    public void close() {
+        synchronized (closeCondition) {
+            closeCondition.notifyAll();
+        }
+
+        getCurrentConsumer().close();
+    }
+
+    private CambriaConsumer getCurrentConsumer() {
+        CambriaConsumer old = null;
+        CambriaConsumer ret;
+
+        synchronized (consLocker) {
+            if (this.newConsumer != null) {
+                // replace old consumer with new consumer
+                old = this.consumer;
+                this.consumer = this.newConsumer;
+                this.newConsumer = null;
+            }
+
+            ret = this.consumer;
+        }
+
+        if (old != null) {
+            old.close();
+        }
+
+        return ret;
+    }
+
+    @Override
+    public void setFilter(String filter) {
+        logger.info("{}: setting DMAAP server-side filter: {}", this, filter);
+        builder.withServerSideFilter(filter);
+
+        try {
+            CambriaConsumer previous;
+            synchronized (consLocker) {
+                previous = this.newConsumer;
+                this.newConsumer = builder.build();
+            }
+
+            if (previous != null) {
+                // there was already a new consumer - close it
+                previous.close();
+            }
+
+        } catch (MalformedURLException | GeneralSecurityException e) {
+            /*
+             * Since an exception occurred, "consumer" still has its old value, thus it should not
+             * be closed at this point.
+             */
+            throw new IllegalArgumentException(e);
+        }
+    }
+
+    @Override
+    public String toString() {
+        return "CambriaConsumerWrapper [fetchTimeout=" + fetchTimeout + "]";
+    }
+}