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 * 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
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package org.apache.pulsar.broker.resourcegroup;

import com.google.common.collect.Sets;
import java.util.Optional;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.TimeUnit;
import lombok.extern.slf4j.Slf4j;
import org.apache.pulsar.broker.PulsarService;
import org.apache.pulsar.broker.resourcegroup.ResourceGroup.BytesAndMessagesCount;
import org.apache.pulsar.broker.resourcegroup.ResourceGroup.ResourceGroupMonitoringClass;
import org.apache.pulsar.broker.resourcegroup.ResourceGroupService.ResourceGroupUsageStatsType;
import org.apache.pulsar.broker.service.BrokerService;
import org.apache.pulsar.broker.service.SharedPulsarBaseTest;
import org.apache.pulsar.broker.service.SharedPulsarCluster;
import org.apache.pulsar.broker.service.Topic;
import org.apache.pulsar.broker.service.persistent.PersistentTopic;
import org.apache.pulsar.broker.service.resource.usage.ResourceUsage;
import org.apache.pulsar.client.api.Consumer;
import org.apache.pulsar.client.api.Message;
import org.apache.pulsar.client.api.Producer;
import org.apache.pulsar.client.api.PulsarClientException;
import org.apache.pulsar.client.api.SubscriptionType;
import org.apache.pulsar.common.naming.NamespaceName;
import org.apache.pulsar.common.naming.TopicName;
import org.apache.pulsar.common.policies.data.TenantInfoImpl;
import org.apache.pulsar.common.policies.data.stats.TopicStatsImpl;
import org.awaitility.Awaitility;
import org.testng.Assert;
import org.testng.annotations.Test;

@Slf4j
public class ResourceGroupUsageAggregationTest extends SharedPulsarBaseTest {
    @org.testng.annotations.BeforeClass(alwaysRun = true)
    public void setupRG() throws Exception {
        PulsarService pulsar = SharedPulsarCluster.get().getPulsarService();
        this.prepareData();

        ResourceQuotaCalculator dummyQuotaCalc = new ResourceQuotaCalculator() {
            @Override
            public boolean needToReportLocalUsage(long currentBytesUsed, long lastReportedBytes,
                                                  long currentMessagesUsed, long lastReportedMessages,
                                                  long lastReportTimeMSecsSinceEpoch) {
                return false;
            }

            @Override
            public long computeLocalQuota(long confUsage, long myUsage, long[] allUsages) {
                return 0;
            }
        };

        ResourceUsageTopicTransportManager transportMgr = new ResourceUsageTopicTransportManager(pulsar);
        this.rgs = new ResourceGroupService(pulsar, TimeUnit.MILLISECONDS, transportMgr, dummyQuotaCalc);
    }

    @Test
    public void testProduceConsumeUsageOnRG() throws Exception {
        testProduceConsumeUsageOnRG(produceConsumePersistentTopic);
        testProduceConsumeUsageOnRG(produceConsumeNonPersistentTopic);
    }

    private void testProduceConsumeUsageOnRG(String topicString) throws Exception {
        ResourceUsagePublisher ruP = new ResourceUsagePublisher() {
            @Override
            public String getID() {
                return activeRG.getID(); }
            @Override
            public void fillResourceUsage(ResourceUsage resourceUsage) {
                activeRG.rgFillResourceUsage(resourceUsage);
                numRgFillUsageCallbacks++;
            }
        };

        ResourceUsageConsumer ruC = new ResourceUsageConsumer() {
            @Override
            public String getID() {
                return activeRG.getID(); }
            @Override
            public void acceptResourceUsage(String broker, ResourceUsage resourceUsage) {
                activeRG.rgResourceUsageListener(broker, resourceUsage);
                numRgUsageListenerCallbacks++;
            }
        };

        rgConfig.setPublishRateInBytes(1500L);
        rgConfig.setPublishRateInMsgs(100);
        rgConfig.setDispatchRateInBytes(4000L);
        rgConfig.setPublishRateInMsgs(500);
        rgs.resourceGroupCreate(activeRgName, rgConfig, ruP, ruC);

        activeRG = rgs.resourceGroupGet(activeRgName);
        Assert.assertNotEquals(activeRG, null);


        Producer<byte[]> producer = pulsarClient.newProducer()
                .topic(topicString)
                .create();

        Consumer<byte[]> consumer = null;
        String subscriptionName = "my-subscription";
        try {
            consumer = pulsarClient.newConsumer()
                    .topic(topicString)
                    .subscriptionName(subscriptionName)
                    .subscriptionType(SubscriptionType.Shared)
                    .subscribe();
        } catch (PulsarClientException p) {
            final String errMsg = String.format("Got exception while building consumer: ex=%s", p.getMessage());
            Assert.fail(errMsg);
        }

        final TopicName myTopic = TopicName.get(topicString);
        final String tenantString = myTopic.getTenant();
        final String nsString = myTopic.getNamespace();
        rgs.registerTenant(activeRgName, tenantString);
        rgs.registerNameSpace(activeRgName, NamespaceName.get(nsString));

        final int numMessagesToSend = 10;
        int sentNumBytes = 0;
        int sentNumMsgs = 0;
        int recvdNumBytes = 0;
        int recvdNumMsgs = 0;
        for (int ix = 0; ix < numMessagesToSend; ix++) {
            byte[] mesg;
            try {
                mesg = String.format("Hi, ix=%s", ix).getBytes();
                producer.send(mesg);
                sentNumBytes += mesg.length;
                sentNumMsgs++;
            } catch (PulsarClientException p) {
                final String errMsg = String.format("Got exception while sending %s-th time: ex=%s", ix,
                        p.getMessage());
                Assert.fail(errMsg);
            }
        }
        producer.close();

        this.verifyStats(topicString, activeRgName, sentNumBytes, sentNumMsgs, recvdNumBytes, recvdNumMsgs,
                true, false);

        Message<byte[]> message = null;
        while (recvdNumMsgs < sentNumMsgs) {
            try {
                message = consumer.receive();
                recvdNumBytes += message.getValue().length;
            } catch (PulsarClientException p) {
                final String errMesg = String.format("Got exception in while receiving %s-th mesg at consumer: ex=%s",
                        recvdNumMsgs, p.getMessage());
                Assert.fail(errMesg);
            }
            recvdNumMsgs++;
        }

        this.verifyStats(topicString, activeRgName, sentNumBytes, sentNumMsgs, recvdNumBytes, recvdNumMsgs,
                true, true);

        consumer.close();
        // cleanup the topic data.
        CompletableFuture<Optional<Topic>> topicFuture =
                SharedPulsarCluster.get().getPulsarService().getBrokerService().getTopics().remove(topicString);
        if (topicFuture != null) {
            Optional<Topic> optTopic = topicFuture.join();
            if (optTopic.isPresent()) {
                Topic topic = optTopic.get();
                if (topic instanceof PersistentTopic) {
                    PersistentTopic persistentTopic = (PersistentTopic) topic;
                    persistentTopic.getSubscription(subscriptionName).deleteForcefully();
                }
            }
        }
        rgs.getTopicConsumeStats().clear();
        rgs.getTopicProduceStats().clear();

        rgs.unRegisterTenant(activeRgName, tenantString);
        rgs.unRegisterNameSpace(activeRgName, NamespaceName.get(nsString));
        rgs.resourceGroupDelete(activeRgName);
    }

    // Verify the app stats with what we see from the broker-service, and the resource-group (which in turn internally
    // derives stats from the broker service)
    // There appears to be a 45-byte message header which is accounted in the stats, additionally to what the
    // application-level sends/receives. Hence, the byte counts are a ">=" check, instead of an equality check.
    private void verifyStats(String topicString, String rgName,
                             int sentNumBytes, int sentNumMsgs,
                             int recvdNumBytes, int recvdNumMsgs,
                             boolean checkProduce, boolean checkConsume)
                                                                throws Exception {
        BrokerService bs = SharedPulsarCluster.get().getPulsarService().getBrokerService();
        Awaitility.await().untilAsserted(() -> {
            TopicStatsImpl topicStats = bs.getTopicStats().get(topicString);
            Assert.assertNotNull(topicStats);
            if (checkProduce) {
                Assert.assertTrue(topicStats.bytesInCounter >= sentNumBytes);
                Assert.assertEquals(sentNumMsgs, topicStats.msgInCounter);
            }
            if (checkConsume) {
                Assert.assertTrue(topicStats.bytesOutCounter >= recvdNumBytes);
                Assert.assertEquals(recvdNumMsgs, topicStats.msgOutCounter);
            }
        });
        if (sentNumMsgs > 0 || recvdNumMsgs > 0) {
            rgs.aggregateResourceGroupLocalUsages();  // hack to ensure aggregator calculation without waiting
            BytesAndMessagesCount prodCounts = rgs.getRGUsage(rgName, ResourceGroupMonitoringClass.Publish,
                    ResourceGroupUsageStatsType.Cumulative);
            BytesAndMessagesCount consCounts = rgs.getRGUsage(rgName, ResourceGroupMonitoringClass.Dispatch,
                    ResourceGroupUsageStatsType.Cumulative);

            // Re-do the getRGUsage.
            // The counts should be equal, since there wasn't any intervening traffic on TEST_PRODUCE_CONSUME_TOPIC.
            BytesAndMessagesCount prodCounts1 = rgs.getRGUsage(rgName, ResourceGroupMonitoringClass.Publish,
                    ResourceGroupUsageStatsType.Cumulative);
            BytesAndMessagesCount consCounts1 = rgs.getRGUsage(rgName, ResourceGroupMonitoringClass.Dispatch,
                    ResourceGroupUsageStatsType.Cumulative);

            Assert.assertEquals(prodCounts1.bytes, prodCounts.bytes);
            Assert.assertEquals(prodCounts1.messages, prodCounts.messages);
            Assert.assertEquals(consCounts1.bytes, consCounts.bytes);
            Assert.assertEquals(consCounts1.messages, consCounts.messages);

            if (checkProduce) {
                Assert.assertTrue(prodCounts.bytes >= sentNumBytes);
                Assert.assertEquals(sentNumMsgs, prodCounts.messages);
            }
            if (checkConsume) {
                Assert.assertTrue(consCounts.bytes >= recvdNumBytes);
                Assert.assertEquals(recvdNumMsgs, consCounts.messages);
            }
        }
    }

    ResourceGroupService rgs;
    ResourceGroup activeRG;
    final org.apache.pulsar.common.policies.data.ResourceGroup rgConfig =
            new org.apache.pulsar.common.policies.data.ResourceGroup();
    final String activeRgName = "runProduceConsume";
    int numRgUsageListenerCallbacks = 0;
    int numRgFillUsageCallbacks = 0;

    final String tenantName = "pulsar-test";
    final String nsName = "test";
    final String tenantAndNsName = tenantName + "/" + nsName;
    final String testProduceConsumeTopicName = "/prod-cons-topic";
    final String produceConsumePersistentTopic = "persistent://" + tenantAndNsName + testProduceConsumeTopicName;
    final String produceConsumeNonPersistentTopic =
                                                "non-persistent://" + tenantAndNsName + testProduceConsumeTopicName;
    private static final int PUBLISH_INTERVAL_SECS = 300;

    // Initial set up for transport manager and producer/consumer clusters/tenants/namespaces/topics.
    private void prepareData() throws Exception {
        SharedPulsarCluster.get().getPulsarService().getConfiguration()
                .setResourceUsageTransportPublishIntervalInSecs(PUBLISH_INTERVAL_SECS);

        SharedPulsarCluster.get().getPulsarService().getConfiguration().setAllowAutoTopicCreation(true);

        final String clusterName = SharedPulsarCluster.CLUSTER_NAME;
        admin.tenants().createTenant(tenantName,
                new TenantInfoImpl(Sets.newHashSet("fakeAdminRole"), Sets.newHashSet(clusterName)));
        admin.namespaces().createNamespace(tenantAndNsName);
        admin.namespaces().setNamespaceReplicationClusters(tenantAndNsName, Sets.newHashSet(clusterName), false);
    }
}
