Github user MikeThomsen commented on a diff in the pull request:
https://github.com/apache/nifi/pull/2614#discussion_r183234762
--- Diff:
nifi-nar-bundles/nifi-pulsar-bundle/nifi-pulsar-processors/src/main/java/org/apache/nifi/processors/pulsar/pubsub/ConsumePulsar_1_X.java
---
@@ -0,0 +1,206 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.nifi.processors.pulsar.pubsub;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+
+import org.apache.nifi.annotation.behavior.InputRequirement;
+import org.apache.nifi.annotation.documentation.CapabilityDescription;
+import org.apache.nifi.annotation.documentation.Tags;
+import org.apache.nifi.annotation.lifecycle.OnStopped;
+import org.apache.nifi.components.PropertyDescriptor;
+import org.apache.nifi.flowfile.FlowFile;
+import org.apache.nifi.logging.ComponentLog;
+import org.apache.nifi.processor.ProcessContext;
+import org.apache.nifi.processor.ProcessSession;
+import org.apache.nifi.processor.Relationship;
+import org.apache.nifi.processor.exception.ProcessException;
+import org.apache.nifi.processors.pulsar.AbstractPulsarConsumerProcessor;
+import org.apache.nifi.pulsar.PulsarClientPool;
+import org.apache.pulsar.client.api.Consumer;
+import org.apache.pulsar.client.api.Message;
+import org.apache.pulsar.client.api.PulsarClientException;
+
+@Tags({"Pulsar", "Get", "Ingest", "Ingress", "Topic", "PubSub", "Consume"})
+@CapabilityDescription("Consumes messages from Apache Pulsar "
+ + "The complementary NiFi processor for sending messages is
PublishPulsar.")
+@InputRequirement(InputRequirement.Requirement.INPUT_FORBIDDEN)
+public class ConsumePulsar_1_X extends AbstractPulsarConsumerProcessor {
+
+ private static final List<PropertyDescriptor> PROPERTIES;
+ private static final Set<Relationship> RELATIONSHIPS;
+
+ static {
+ final List<PropertyDescriptor> properties = new ArrayList<>();
+ properties.add(PULSAR_CLIENT_SERVICE);
+ properties.add(TOPIC);
+ properties.add(SUBSCRIPTION);
+ properties.add(ASYNC_ENABLED);
+ properties.add(MAX_ASYNC_REQUESTS);
+ properties.add(ACK_TIMEOUT);
+ properties.add(PRIORITY_LEVEL);
+ properties.add(RECEIVER_QUEUE_SIZE);
+ properties.add(SUBSCRIPTION_TYPE);
+ properties.add(MAX_WAIT_TIME);
+
+ PROPERTIES = Collections.unmodifiableList(properties);
+
+ final Set<Relationship> relationships = new HashSet<>();
+ relationships.add(REL_SUCCESS);
+ RELATIONSHIPS = Collections.unmodifiableSet(relationships);
+ }
+
+ @Override
+ public Set<Relationship> getRelationships() {
+ return RELATIONSHIPS;
+ }
+
+ @Override
+ protected List<PropertyDescriptor> getSupportedPropertyDescriptors() {
+ return PROPERTIES;
+ }
+
+ @Override
+ public void onTrigger(ProcessContext context, ProcessSession session)
throws ProcessException {
+
+ try {
+ if (context.getProperty(ASYNC_ENABLED).asBoolean()) {
+ // Launch consumers
+ consumeAsync(context, session);
+
+ // Handle completed consumers
+ handleAsync(context, session);
+
+ } else {
+ consume(context, session);
+ }
+ } catch (PulsarClientException e) {
+ getLogger().error("Unable to consume from Pulsar Topic ", e);
+ context.yield();
+ throw new ProcessException(e);
+ }
+
+ }
+
+ private void handleAsync(ProcessContext context, ProcessSession
session) {
+
+ try {
+ Future<Message> done = consumerService.take();
+ Message msg = done.get();
+
+ if (msg != null) {
+ FlowFile flowFile = null;
+ final byte[] value = msg.getData();
+ if (value != null && value.length > 0) {
+ flowFile = session.create();
+ flowFile = session.write(flowFile, out -> {
+ out.write(value);
+ });
+
+ session.getProvenanceReporter().receive(flowFile, "From
" + getWrappedConsumer(context).getTransitURL());
+ session.transfer(flowFile, REL_SUCCESS);
+ session.commit();
--- End diff --
You might want to consider doing this every X number of flowfiles or based
on a timer.
---