sql/connector/ExternalCommandRunner.java

0001 /*
0002  * Licensed to the Apache Software Foundation (ASF) under one or more
0003  * contributor license agreements.  See the NOTICE file distributed with
0004  * this work for additional information regarding copyright ownership.
0005  * The ASF licenses this file to You under the Apache License, Version 2.0
0006  * (the "License"); you may not use this file except in compliance with
0007  * the License.  You may obtain a copy of the License at
0008  *
0009  *    http://www.apache.org/licenses/LICENSE-2.0
0010  *
0011  * Unless required by applicable law or agreed to in writing, software
0012  * distributed under the License is distributed on an "AS IS" BASIS,
0013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0014  * See the License for the specific language governing permissions and
0015  * limitations under the License.
0016  */
0017
0018 package org.apache.spark.sql.connector;
0019
0020 import org.apache.spark.annotation.Unstable;
0021 import org.apache.spark.sql.util.CaseInsensitiveStringMap;
0022
0023 /**
0024  * An interface to execute an arbitrary string command inside an external execution engine rather
0025  * than Spark. This could be useful when user wants to execute some commands out of Spark. For
0026  * example, executing custom DDL/DML command for JDBC, creating index for ElasticSearch, creating
0027  * cores for Solr and so on.
0028  * <p>
0029  * This interface will be instantiated when end users call `SparkSession#executeCommand`.
0030  *
0031  * @since 3.0.0
0032  */
0033 @Unstable
0034 public interface ExternalCommandRunner {
0035
0036   /**
0037    * Execute the given command.
0038    *
0039    * @param command The command string provided by users.
0040    * @param options The user-specified case-insensitive options.
0041    *
0042    * @return The output of the command.
0043    */
0044   String[] executeCommand(String command, CaseInsensitiveStringMap options);
0045 }