How to import to GraphFrame the text time follow structure

Question

I have a file follow structure.Where first column it's nodeID. After ":" it's a node which has a connection with nodeID. Each nodeID can have more than one connection.

0: 5305811,
1: 4798401,
2: 7922543,
3: 7195074,
4: 6399935,
5: 5697217,
6: 5357407,
7: 4798401,
8: 629131,5330605,6481451,6280292,6909396,7325128,
...

How to apply transformations to import to GraphFrame?

Answer 1

import org.apache.spark.sql.SparkSession
import org.apache.spark.sql.functions._
import org.apache.spark.sql.types.LongType
import org.graphframes.GraphFrame
import scala.util.Try


val spark = SparkSession.builder()
  .master("local[2]")
  .appName("test")
  .getOrCreate()

spark.sparkContext.setCheckpointDir(spark.conf.getOption(s"spark.checkpointdir").getOrElse("/tmp"))

import spark.implicits._

def cleanIds = udf((ids: Seq[String]) => ids.flatMap(x => Try(x.trim.toLong).toOption))

val ds = spark
  .read
  .option("mode", "PERMISSIVE")
  .option("header", "false")
  .option("delimiter", ":")
  .csv("src/main/resources/connections.txt")
  .toDF("id", "links")
  .select(
    'id.cast(LongType),
    cleanIds(split(trim('links), ",")).as("links"))
  .cache()


val vertices = ds.select('id).distinct()

val edges = ds.select(
  'id.as("src"),
  explode('links).as("dst")
)

val graphFrame = GraphFrame(vertices, edges)

val connectedComponents = graphFrame.connectedComponents.run()

connectedComponents
  .groupBy('component).agg(
  collect_list(struct('id)).as("vertices")
).show(false)

Given input like this:

0: 5,6,
1: 4,
2: 3,4,5,
3: 2,
4: 2,1,
5: 2,0,
6: 0,7,
10: 11,13,
11: 12,14,
12: 13,14,
13: 10,12,
14: 11,12,

This will create a vertex dataframe looking like this:

+---+
| id|
+---+
|  0|
|  6|
|  5|
|  1|
| 10|
|  3|
| 12|
| 11|
|  2|
|  4|
| 13|
| 14|
+---+

and edges like this:

+---+---+
|src|dst|
+---+---+
|  0|  5|
|  0|  6|
|  1|  4|
|  2|  3|
|  2|  4|
|  2|  5|
|  3|  2|
|  4|  2|
|  4|  1|
|  5|  2|
|  5|  0|
|  6|  0|
|  6|  7|
| 10| 11|
| 10| 13|
| 11| 12|
| 11| 14|
| 12| 13|
| 12| 14|
| 13| 10|
+---+---+

and connected components like this:

+---------+-----------------------------------+
|component|vertices                           |
+---------+-----------------------------------+
|0        |[[0], [6], [5], [1], [3], [2], [4]]|
|10       |[[10], [12], [11], [13], [14]]     |
+---------+-----------------------------------+