Spark讀寫Elasticsearch

版本說明

Spark:2.3.1

Elasticsearch: elasticsearch-6.4.0

1 Scala環境下Spark讀寫Elasticsearch

1.1 依賴包

1.1.1 Spark依賴

<dependency>
    <groupId>org.apache.spark</groupId>
    <artifactId>spark-core_2.11</artifactId>
    <version>${spark.version}</
 
version>
    <exclusions>
        <exclusion>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
        </exclusion>
    </exclusions>
</dependency>

1.1.2 Elasticeach依賴

<!--elasticsearch-->
<dependency
 
>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch-hadoop</artifactId>
    <version>6.4.0</version>
</dependency>

1.2 RDD讀寫ES

使用RDD讀寫ES，主要是使用了SparkContext()的esRDD()和saveToEs()兩個方法。但是這個兩個方法需要引入es的包之後才有

import org.elasticsearch.spark._
 

1.2.1 寫資料到ES

在這之前先寫一個case class 用於建立RDD

case class Course(name: String, credit: Int)

 val conf = new SparkConf().setAppName(this.getClass.getSimpleName).setMaster("local")
    conf.set("es.nodes", "192.168.1.188")
    conf.set("es.port", "9200")
    conf.set("es.index.auto.create", "true")
    val sc = new SparkContext(conf)
 	//rdd寫es
    val courseRdd = sc.makeRDD(Seq(Course("Hadoop", 4), Course("Spark", 3), Course("Kafka", 4)))
    courseRdd.saveToEs("/course/rdd")
    

1.2.2 從ES讀資料

 //rdd讀es
    val esCourseRdd = sc.esRDD("/course/rdd")
    esCourseRdd.foreach(c => {
      println(c.toString())
    })
    /**
      * (vNHejmUBdoXqZPoSocAx,Map(name -> Kafka, credit -> 4))
      * (u9HejmUBdoXqZPoSocAx,Map(name -> Spark, credit -> 3))
      * (utHejmUBdoXqZPoSocAx,Map(name -> Hadoop, credit -> 4))
      */

1.3 DataFrame讀寫ES

如果想使用spark sql讀寫ES同樣需要引入es的包

    import org.elasticsearch.spark.sql._

1.3.1 DataFrame寫資料到ES

  //dataframe寫es
    val df = spark.read.format("csv").option("header", true).option("inferSchema", true).load("hdfs://192.168.1.188:9000/data/Beijing_2017_HourlyPM25_created20170803.csv")
    df.select("Year", "Month", "Day", "Hour", "Value").saveToEs("/csv/dataframe")
  

1.3.2 DataFrame從ES讀資料

//dataframe讀es
    val esDf = spark.esDF("/csv/dataframe")
    esDf.show()

    /**
      * +---+----+-----+-----+----+
      * |Day|Hour|Month|Value|Year|
      * +---+----+-----+-----+----+
      * |  1|   0|    1|  505|2017|
      * |  1|   2|    1|  466|2017|
      * |  1|  14|    1|  596|2017|
      * |  1|  17|    1|  522|2017|
      * |  1|  21|    1|  452|2017|
      * |  2|   1|    1|  466|2017|
      * |  2|   7|    1|   93|2017|
      * |  2|   8|    1|   27|2017|
      * |  2|   9|    1|   17|2017|
      * |  2|  13|    1|  251|2017|
      * |  2|  16|    1|  251|2017|
      * |  3|   2|    1|  341|2017|
      * |  3|   8|    1|  365|2017|
      * |  3|   9|    1|  361|2017|
      * |  3|  21|    1|  542|2017|
      * |  3|  22|    1|  548|2017|
      * |  4|   3|    1|  590|2017|
      * |  4|   6|    1|  482|2017|
      * |  4|  17|    1|  323|2017|
      * |  4|  22|    1|  369|2017|
      * +---+----+-----+-----+----+
      */

1.4 完整程式碼

package com.hollysys.spark.elasticsearch

import org.apache.spark.{SparkConf, SparkContext}
import org.apache.spark.sql.SparkSession

/**
  * Created by shirukai on 2018/8/31
  * spark 讀寫ES
  */
object EsTest {
  def main(args: Array[String]): Unit = {
    import org.elasticsearch.spark._
    import org.elasticsearch.spark.sql._
    val conf = new SparkConf().setAppName(this.getClass.getSimpleName).setMaster("local")
    conf.set("es.nodes", "192.168.1.188")
    conf.set("es.port", "9200")
    conf.set("es.index.auto.create", "true")
    val sc = new SparkContext(conf)
    val spark = SparkSession.builder.config(conf).getOrCreate()


    //rdd寫es
    val courseRdd = sc.makeRDD(Seq(Course("Hadoop", 4), Course("Spark", 3), Course("Kafka", 4)))
    courseRdd.saveToEs("/course/rdd")

    //rdd讀es
    val esCourseRdd = sc.esRDD("/course/rdd")
    esCourseRdd.foreach(c => {
      println(c.toString())
    })
    /**
      * (vNHejmUBdoXqZPoSocAx,Map(name -> Kafka, credit -> 4))
      * (u9HejmUBdoXqZPoSocAx,Map(name -> Spark, credit -> 3))
      * (utHejmUBdoXqZPoSocAx,Map(name -> Hadoop, credit -> 4))
      */

    //dataframe寫es
    val df = spark.read.format("csv").option("header", true).option("inferSchema", true).load("hdfs://192.168.1.188:9000/data/Beijing_2017_HourlyPM25_created20170803.csv")
    df.select("Year", "Month", "Day", "Hour", "Value").saveToEs("/csv/dataframe")
    //dataframe讀es
    val esDf = spark.esDF("/csv/dataframe")
    esDf.show()

    /**
      * +---+----+-----+-----+----+
      * |Day|Hour|Month|Value|Year|
      * +---+----+-----+-----+----+
      * |  1|   0|    1|  505|2017|
      * |  1|   2|    1|  466|2017|
      * |  1|  14|    1|  596|2017|
      * |  1|  17|    1|  522|2017|
      * |  1|  21|    1|  452|2017|
      * |  2|   1|    1|  466|2017|
      * |  2|   7|    1|   93|2017|
      * |  2|   8|    1|   27|2017|
      * |  2|   9|    1|   17|2017|
      * |  2|  13|    1|  251|2017|
      * |  2|  16|    1|  251|2017|
      * |  3|   2|    1|  341|2017|
      * |  3|   8|    1|  365|2017|
      * |  3|   9|    1|  361|2017|
      * |  3|  21|    1|  542|2017|
      * |  3|  22|    1|  548|2017|
      * |  4|   3|    1|  590|2017|
      * |  4|   6|    1|  482|2017|
      * |  4|  17|    1|  323|2017|
      * |  4|  22|    1|  369|2017|
      * +---+----+-----+-----+----+
      */
  }

}

case class Course(name: String, credit: Int)

2 pyspark寫資料到Elasticsearch

使用pyspark寫資料到Elasticsearch主要是利用的寫入外部資料來源，需要org.elasticsearch.spark.sql相關的jar包

2.1 下載相關jar包

使用pyspark寫資料到es需要依賴elasticsearch-spark-20_2.11.jar包，可以到maven倉庫下載。

下載地址：http://mvnrepository.com/artifact/org.elasticsearch/elasticsearch-spark-20_2.11/6.4.0

2.2 pyspark中使用

pyspark2es.py

# encoding: utf-8
"""
Created by shirukai on 2018/8/31
"""
from pyspark.sql import SparkSession

if __name__ == '__main__':
    spark = SparkSession.builder.appName("pyspark2es").getOrCreate()
    data = [
        (1, "Kafka"),
        (2, "Spark"),
        (3, "Hadoop")
    ]
    df = spark.createDataFrame(data, schema=['id', 'name'])
    df.write.format("org.elasticsearch.spark.sql").option("es.nodes", "192.168.1.196:9200").mode("overwrite").save(
        "pyspark2es/python")
    spark.stop()

使用spark-submit提交任務

bin/spark-submit --master local --jars /Users/shirukai/apps/spark-2.3.1/jars/elasticsearch-spark-20_2.11-6.4.0.jar  /Users/shirukai/apps/spark-2.3.1/script/pyspark2es.py