org.apache.spark.api.resource.ResourceDiscoveryPlugin Maven / Gradle / Ivy
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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,
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* See the License for the specific language governing permissions and
* limitations under the License.
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package org.apache.spark.api.resource;
import java.util.Optional;
import org.apache.spark.annotation.DeveloperApi;
import org.apache.spark.SparkConf;
import org.apache.spark.resource.ResourceInformation;
import org.apache.spark.resource.ResourceRequest;
/**
* :: DeveloperApi ::
* A plugin that can be dynamically loaded into a Spark application to control how custom
* resources are discovered. Plugins can be chained to allow different plugins to handle
* different resource types.
*
* Plugins must implement the function discoveryResource.
*
* @since 3.0.0
*/
@DeveloperApi
public interface ResourceDiscoveryPlugin {
/**
* Discover the addresses of the requested resource.
*
* This method is called early in the initialization of the Spark Executor/Driver/Worker.
* This function is responsible for discovering the addresses of the resource which Spark will
* then use for scheduling and eventually providing to the user.
* Depending on the deployment mode and and configuration of custom resources, this could be
* called by the Spark Driver, the Spark Executors, in standalone mode the Workers, or all of
* them. The ResourceRequest has a ResourceID component that can be used to distinguish which
* component it is called from and what resource its being called for.
* This will get called once for each resource type requested and its the responsibility of
* this function to return enough addresses of that resource based on the request. If
* the addresses do not meet the requested amount, Spark will fail.
* If this plugin doesn't handle a particular resource, it should return an empty Optional
* and Spark will try other plugins and then last fall back to the default discovery script
* plugin.
*
* @param request The ResourceRequest that to be discovered.
* @param sparkConf SparkConf
* @return An {@link Optional} containing a {@link ResourceInformation} object containing
* the resource name and the addresses of the resource. If it returns {@link Optional#EMPTY}
* other plugins will be called.
*/
Optional discoverResource(ResourceRequest request, SparkConf sparkConf);
}