PawasChhokra commented on a change in pull request #1449: URL: https://github.com/apache/samza/pull/1449#discussion_r536394598
########## File path: samza-core/src/main/java/org/apache/samza/coordinator/JobCoordinatorMetadataManager.java ########## @@ -0,0 +1,254 @@ +/* + * 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.samza.coordinator; + +import com.google.common.base.Preconditions; +import com.google.common.collect.ImmutableSortedSet; +import com.google.common.hash.Funnel; +import com.google.common.hash.Hashing; +import com.google.common.hash.PrimitiveSink; +import java.util.Map; +import java.util.SortedMap; +import java.util.SortedSet; +import java.util.TreeMap; +import org.apache.commons.lang3.StringUtils; +import org.apache.samza.config.Config; +import org.apache.samza.coordinator.stream.CoordinatorStreamValueSerde; +import org.apache.samza.coordinator.stream.messages.SetJobCoordinatorMetadataMessage; +import org.apache.samza.job.JobCoordinatorMetadata; +import org.apache.samza.job.model.JobModel; +import org.apache.samza.metadatastore.MetadataStore; +import org.apache.samza.metrics.Counter; +import org.apache.samza.metrics.Gauge; +import org.apache.samza.metrics.MetricsRegistry; +import org.apache.samza.serializers.Serde; +import org.apache.samza.serializers.model.SamzaObjectMapper; +import org.codehaus.jackson.map.ObjectMapper; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +/** + * A class to manage read and writes of {@link JobCoordinatorMetadata} to {@link MetadataStore}. It also provides + * additional helper functionalities to generate {@link JobCoordinatorMetadata} and check for changes across runs. + */ +public final class JobCoordinatorMetadataManager { + private static final Logger LOG = LoggerFactory.getLogger(JobCoordinatorMetadataManager.class); + private static final String APPLICATION_ATTEMPT_COUNT = "applicationAttemptCount"; + private static final String JOB_COORDINATOR_MANAGER_METRICS = "job-coordinator-manager"; + private static final String JOB_MODEL_CHANGED = "jobModelChanged"; + private static final String CONFIG_CHANGED = "configChanged"; + private static final String NEW_DEPLOYMENT = "newDeployment"; + + + private final Counter applicationAttemptCount; + private final Gauge<Integer> jobModelChangedAcrossApplicationAttempt; + private final Gauge<Integer> configChangedAcrossApplicationAttempt; + private final Gauge<Integer> newDeployment; + private final MetadataStore metadataStore; + private final ObjectMapper metadataMapper = SamzaObjectMapper.getObjectMapper(); + private final Serde<String> valueSerde; + private final String clusterType; + + public JobCoordinatorMetadataManager(MetadataStore metadataStore, String clusterType, MetricsRegistry metricsRegistry) { + this.clusterType = clusterType; + this.metadataStore = metadataStore; + this.valueSerde = new CoordinatorStreamValueSerde(SetJobCoordinatorMetadataMessage.TYPE); + + applicationAttemptCount = metricsRegistry.newCounter(JOB_COORDINATOR_MANAGER_METRICS, APPLICATION_ATTEMPT_COUNT); + configChangedAcrossApplicationAttempt = + metricsRegistry.newGauge(JOB_COORDINATOR_MANAGER_METRICS, CONFIG_CHANGED, 0); + jobModelChangedAcrossApplicationAttempt = + metricsRegistry.newGauge(JOB_COORDINATOR_MANAGER_METRICS, JOB_MODEL_CHANGED, 0); + newDeployment = metricsRegistry.newGauge(JOB_COORDINATOR_MANAGER_METRICS, NEW_DEPLOYMENT, 0); + } + + /** + * Generates {@link JobCoordinatorMetadata} for the {@link JobCoordinator}. + * + * Epoch ID - It is generated by {@link #fetchEpochIdForJobCoordinator()}. Refer to the javadocs for more Review comment: Can we also add an example of an epoch ID, config ID and job model ID for better visualization? ########## File path: samza-api/src/main/java/org/apache/samza/job/JobCoordinatorMetadata.java ########## @@ -0,0 +1,107 @@ +/* + * 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.samza.job; + +import java.util.Objects; +import org.apache.samza.annotation.InterfaceStability; + +/** + * A data model to represent the metadata of the job coordinator. The metadata refers to attributes of job coordinator + * scoped to attempt within a deployment. For the purpose of this data model, deployment and attempt as defined Review comment: Change "attempt as" to "attempt are". ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org
