spark图操作

Posted 2021-03-13 fionacai

spark graphx图操作

import org.apache.spark.graphx.{Edge, Graph, VertexId}
import org.apache.spark.rdd.RDD
import org.apache.spark.{SparkConf, SparkContext}

object PropertiesGraph {
  def main(args: Array[String]): Unit = {
    val conf = new SparkConf().setAppName("graph").setMaster("local[*]")
    val sc = new SparkContext(conf)
    sc.setLogLevel("OFF")
    //定义点
    val users: RDD[(VertexId, (String, String))] = sc.parallelize(Array(
      (3L, ("hanmeimei", "student")),
      (7L, ("Lilei", "postdoc")),
      (5L, ("zixuan", "prof")),
      (2L, ("haoran", "prof"))
    )
    )
    //定义边
    val relationships: RDD[(Edge[String])] = sc.parallelize(
      Array(
        Edge(3L, 7L, "cooperate"),
        Edge(5L, 7L, "advisor"),
        Edge(2L, 5L, "colleague")
      )
    )
    val defaultUser = ("Jack ma", "defaultUser")
    val graph = Graph(users, relationships, defaultUser)
    //找到图中属性是student的点
    graph.vertices.filter{case (id,(name, work))=> work=="student"}
      .collect().foreach{case (id,(name, work))=> println(s"${name} is ${work}") }

    //找到图中属性为advisor的边
    graph.edges.filter(x=> x.attr=="advisor")
      .collect().foreach(x=>println(s"${x.srcId} to ${x.dstId} 属性为 ${x.attr}"))

    //出度入度
    def max(a:(VertexId,Int),b:(VertexId,Int)) : (VertexId,Int)={
      if(a._2>b._2) a else b
    }
    println("最大的出度" + graph.outDegrees.reduce(max))
    println("最大的入度" + graph.inDegrees.reduce(max))
    println("最大的度" + graph.degrees.reduce(max))
    // 给每个点的职业属性上加一个字符串
    graph.mapVertices{case (id, (name,work))=>(id,(name, work+"spark"))}
      .vertices.collect().foreach(println)
    //triplet
    //给图中每个元组的edge属性值设置为源的属性值+边的属性值+目标点的属性值
    graph.mapTriplets((x=>x.srcAttr._2 + "+" + x.attr + "+" + x.dstAttr._2))
      .edges.collect().foreach(println)
    graph.triplets.map(x=>x.srcAttr._1 + "is the" + x.attr + "of" + x.dstAttr._1).foreach(println)
    //删除节点，构建子图
    val validGraph = graph.subgraph(vpred=(id, attr) => attr._2 != "postdoc")
    validGraph.vertices.foreach(println)
    validGraph.triplets.map(x=>x.srcAttr._1 + "is the" + x.attr + "of" + x.dstAttr._1).foreach(println)
    //构建职业为professor的子图
    val subGraph = graph.subgraph(vpred = (id,attr)=>attr._2=="professor")
    subGraph.vertices.collect().foreach(x=>println(s"${x._2._1} is ${x._2._2}"))
  }
}

spark连接neo4j操作

import org.apache.spark.SparkConf
import org.apache.spark.api.java.JavaSparkContext
import org.apache.spark.graphx.Graph
import org.apache.spark.ml.tree.InternalNode
import org.neo4j.spark.Neo4j

object SparkGraphxConnector {
  def main(args: Array[String]): Unit = {
    val conf = new SparkConf()
      .setAppName("neo4j")
      .setMaster("local[*]")
      .set("spark.neo4j.bolt.url","bolt://192.168.1.21")
      .set("spark.neo4j.bolt.user","neo4j")
      .set("spark.neo4j.bolt.password","123")

    val sc = new JavaSparkContext(conf)
    sc.setLogLevel("OFF")
    val neo4j = Neo4j(sc)
    val rdd = neo4j.cypher("match (n:Person) return n").loadRowRdd
    val personRDD = rdd.map(row =>{
      val map = row.get(0).asInstanceOf[InternalNode]
      new Person(map.get("home").asString(),
        map.get("name").asString(),
        map.get("personId").asString())
    })
    personRDD.foreach(println)
    val graphQuery = "match (p:Person) -[r]-(a:Person) return id(p) as source,id(a) as target, type(r) as value"
    val graph: Graph[String,String] = neo4j.rels(graphQuery).loadGraph
    graph.edges.foreach(println(_))
  }
  case class Person(
                   val home:String,
                   val name:String,
                   val person: String
                   )
}