hadoop TimelineReader 源码

haddop TimelineReader 代码

文件路径：/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/TimelineReader.java

/**
 * 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.hadoop.yarn.server.timelineservice.storage;

import java.io.IOException;

import java.util.Set;
import org.apache.hadoop.classification.InterfaceAudience.Private;
import org.apache.hadoop.classification.InterfaceStability.Unstable;
import org.apache.hadoop.service.Service;
import org.apache.hadoop.yarn.api.records.timeline.TimelineHealth;
import org.apache.hadoop.yarn.api.records.timelineservice.TimelineEntity;
import org.apache.hadoop.yarn.server.timelineservice.reader.TimelineDataToRetrieve;
import org.apache.hadoop.yarn.server.timelineservice.reader.TimelineEntityFilters;
import org.apache.hadoop.yarn.server.timelineservice.reader.TimelineReaderContext;

/** ATSv2 reader interface. */
@Private
@Unstable
public interface TimelineReader extends Service {

  /**
   * Possible fields to retrieve for {@link #getEntities} and
   * {@link #getEntity}.
   */
  public enum Field {
    ALL,
    EVENTS,
    INFO,
    METRICS,
    CONFIGS,
    RELATES_TO,
    IS_RELATED_TO
  }

  /**
   * <p>The API to fetch the single entity given the identifier(depending on
   * the entity type) in the scope of the given context.</p>
   * @param context Context which defines the scope in which query has to be
   *    made. Use getters of {@link TimelineReaderContext} to fetch context
   *    fields. Context contains the following :<br>
   *    <ul>
   *    <li><b>entityType</b> - Entity type(mandatory).</li>
   *    <li><b>clusterId</b> - Identifies the cluster(mandatory).</li>
   *    <li><b>userId</b> - Identifies the user.</li>
   *    <li><b>flowName</b> - Context flow name.</li>
   *    <li><b>flowRunId</b> - Context flow run id.</li>
   *    <li><b>appId</b> - Context app id.</li>
   *    <li><b>entityId</b> - Entity id.</li>
   *    </ul>
   *    Fields in context which are mandatory depends on entity type. Entity
   *    type is always mandatory. In addition to entity type, below is the list
   *    of context fields which are mandatory, based on entity type.<br>
   *    <ul>
   *    <li>If entity type is YARN_FLOW_RUN (i.e. query to fetch a specific flow
   *    run), clusterId, userId, flowName and flowRunId are mandatory.</li>
   *    <li>If entity type is YARN_APPLICATION (i.e. query to fetch a specific
   *    app), query is within the scope of clusterId, userId, flowName,
   *    flowRunId and appId. But out of this, only clusterId and appId are
   *    mandatory. If only clusterId and appId are supplied, backend storage
   *    must fetch the flow context information i.e. userId, flowName and
   *    flowRunId first and based on that, fetch the app. If flow context
   *    information is also given, app can be directly fetched.
   *    </li>
   *    <li>For other entity types (i.e. query to fetch generic entity), query
   *    is within the scope of clusterId, userId, flowName, flowRunId, appId,
   *    entityType and entityId. But out of this, only clusterId, appId,
   *    entityType and entityId are mandatory. If flow context information is
   *    not supplied, backend storage must fetch the flow context information
   *    i.e. userId, flowName and flowRunId first and based on that, fetch the
   *    entity. If flow context information is also given, entity can be
   *    directly queried.
   *    </li>
   *    </ul>
   * @param dataToRetrieve Specifies which data to retrieve for the entity. Use
   *    getters of TimelineDataToRetrieve class to fetch dataToRetrieve
   *    fields. All the dataToRetrieve fields are optional. Refer to
   *    {@link TimelineDataToRetrieve} for details.
   * @return A <cite>TimelineEntity</cite> instance or null. The entity will
   *    contain the metadata plus the given fields to retrieve.<br>
   *    If entityType is YARN_FLOW_RUN, entity returned is of type
   *    <cite>FlowRunEntity</cite>.<br>
   *    For all other entity types, entity returned is of type
   *    <cite>TimelineEntity</cite>.
   * @throws IOException if there is an exception encountered while fetching
   *    entity from backend storage.
   */
  TimelineEntity getEntity(TimelineReaderContext context,
      TimelineDataToRetrieve dataToRetrieve) throws IOException;

  /**
   * <p>The API to search for a set of entities of the given entity type in
   * the scope of the given context which matches the given predicates. The
   * predicates include the created time window, limit to number of entities to
   * be returned, and the entities can be filtered by checking whether they
   * contain the given info/configs entries in the form of key/value pairs,
   * given metrics in the form of metricsIds and its relation with metric
   * values, given events in the form of the Ids, and whether they relate to/are
   * related to other entities. For those parameters which have multiple
   * entries, the qualified entity needs to meet all or them.</p>
   *
   * @param context Context which defines the scope in which query has to be
   *    made. Use getters of {@link TimelineReaderContext} to fetch context
   *    fields. Context contains the following :<br>
   *    <ul>
   *    <li><b>entityType</b> - Entity type(mandatory).</li>
   *    <li><b>clusterId</b> - Identifies the cluster(mandatory).</li>
   *    <li><b>userId</b> - Identifies the user.</li>
   *    <li><b>flowName</b> - Context flow name.</li>
   *    <li><b>flowRunId</b> - Context flow run id.</li>
   *    <li><b>appId</b> - Context app id.</li>
   *    </ul>
   *    Although entityIdPrefix and entityId are also part of context,
   *    it has no meaning for getEntities.<br>
   *    Fields in context which are mandatory depends on entity type. Entity
   *    type is always mandatory. In addition to entity type, below is the list
   *    of context fields which are mandatory, based on entity type.<br>
   *    <ul>
   *    <li>If entity type is YARN_FLOW_ACTIVITY (i.e. query to fetch flows),
   *    only clusterId is mandatory.
   *    </li>
   *    <li>If entity type is YARN_FLOW_RUN (i.e. query to fetch flow runs),
   *    clusterId, userId and flowName are mandatory.</li>
   *    <li>If entity type is YARN_APPLICATION (i.e. query to fetch apps), we
   *    can either get all apps within the context of flow name or within the
   *    context of flow run. If apps are queried within the scope of flow name,
   *    clusterId, userId and flowName are supplied. If they are queried within
   *    the scope of flow run, clusterId, userId, flowName and flowRunId are
   *    supplied.</li>
   *    <li>For other entity types (i.e. query to fetch generic entities), query
   *    is within the scope of clusterId, userId, flowName, flowRunId, appId and
   *    entityType. But out of this, only clusterId, appId and entityType are
   *    mandatory. If flow context information is not supplied, backend storage
   *    must fetch the flow context information i.e. userId, flowName and
   *    flowRunId first and based on that, fetch the entities. If flow context
   *    information is also given, entities can be directly queried.
   *    </li>
   *    </ul>
   * @param filters Specifies filters which restrict the number of entities
   *    to return. Use getters of TimelineEntityFilters class to fetch
   *    various filters. All the filters are optional. Refer to
   *    {@link TimelineEntityFilters} for details.
   * @param dataToRetrieve Specifies which data to retrieve for each entity. Use
   *    getters of TimelineDataToRetrieve class to fetch dataToRetrieve
   *    fields. All the dataToRetrieve fields are optional. Refer to
   *    {@link TimelineDataToRetrieve} for details.
   * @return A set of <cite>TimelineEntity</cite> instances of the given entity
   *    type in the given context scope which matches the given predicates
   *    ordered by enitityIdPrefix(for generic entities only).
   *    Each entity will only contain
   *    the metadata(id, type , idPrefix and created time) plus the given
   *    fields to retrieve.
   *    <br>
   *    If entityType is YARN_FLOW_ACTIVITY, entities returned are of type
   *    <cite>FlowActivityEntity</cite>.<br>
   *    If entityType is YARN_FLOW_RUN, entities returned are of type
   *    <cite>FlowRunEntity</cite>.<br>
   *    For all other entity types, entities returned are of type
   *    <cite>TimelineEntity</cite>.
   * @throws IOException if there is an exception encountered while fetching
   *    entity from backend storage.
   */
  Set<TimelineEntity> getEntities(
      TimelineReaderContext context,
      TimelineEntityFilters filters,
      TimelineDataToRetrieve dataToRetrieve) throws IOException;

  /**
   * The API to list all available entity types of the given context.
   *
   * @param context A context defines the scope of this query. The incoming
   * context should contain at least the cluster id and application id.
   *
   * @return A set of entity types available in the given context.
   *
   * @throws IOException if an exception occurred while listing from backend
   * storage.
   */
  Set<String> getEntityTypes(TimelineReaderContext context) throws IOException;

  /**
   * Check if reader connection is working properly.
   *
   * @return True if reader connection works as expected, false otherwise.
   */
  TimelineHealth getHealthStatus();
}

相关信息

hadoop 源码目录

相关文章

hadoop FileSystemTimelineReaderImpl 源码

hadoop FileSystemTimelineWriterImpl 源码

hadoop NoOpTimelineReaderImpl 源码

hadoop NoOpTimelineWriterImpl 源码

hadoop OfflineAggregationWriter 源码

hadoop SchemaCreator 源码

hadoop TimelineAggregationTrack 源码

hadoop TimelineSchemaCreator 源码

hadoop TimelineStorageMonitor 源码

hadoop TimelineWriter 源码