I want to read data from a confluent cloud topic and then write in another topic.
At localhost, I haven't had any major problems. But the schema registry of confluent cloud requires to pass some authentication data that I don't know how to enter them:
basic.auth.credentials.source=USER_INFO
schema.registry.basic.auth.user.info=:
schema.registry.url=https://xxxxxxxxxx.confluent.cloudBlockquote
Below is the current code:
import com.databricks.spark.avro.SchemaConverters
import io.confluent.kafka.schemaregistry.client.{CachedSchemaRegistryClient, SchemaRegistryClient}
import io.confluent.kafka.serializers.AbstractKafkaAvroDeserializer
import org.apache.avro.Schema
import org.apache.avro.generic.GenericRecord
import org.apache.spark.sql.SparkSession
object AvroConsumer {
  private val topic = "transactions"
  private val kafkaUrl = "http://localhost:9092"
  private val schemaRegistryUrl = "http://localhost:8081"
  private val schemaRegistryClient = new CachedSchemaRegistryClient(schemaRegistryUrl, 128)
  private val kafkaAvroDeserializer = new AvroDeserializer(schemaRegistryClient)
  private val avroSchema = schemaRegistryClient.getLatestSchemaMetadata(topic + "-value").getSchema
  private var sparkSchema = SchemaConverters.toSqlType(new Schema.Parser().parse(avroSchema))
  def main(args: Array[String]): Unit = {
    val spark = SparkSession
      .builder
      .appName("ConfluentConsumer")
      .master("local[*]")
      .getOrCreate()
    spark.sparkContext.setLogLevel("ERROR")
    spark.udf.register("deserialize", (bytes: Array[Byte]) =>
      DeserializerWrapper.deserializer.deserialize(bytes)
    )
    val kafkaDataFrame = spark
      .readStream
      .format("kafka")
      .option("kafka.bootstrap.servers", kafkaUrl)
      .option("subscribe", topic)
      .load()
    val valueDataFrame = kafkaDataFrame.selectExpr("""deserialize(value) AS message""")
    import org.apache.spark.sql.functions._
    val formattedDataFrame = valueDataFrame.select(
      from_json(col("message"), sparkSchema.dataType).alias("parsed_value"))
      .select("parsed_value.*")
    formattedDataFrame
      .writeStream
      .format("console")
      .option("truncate", false)
      .start()
      .awaitTermination()
  }
  object DeserializerWrapper {
    val deserializer = kafkaAvroDeserializer
  }
  class AvroDeserializer extends AbstractKafkaAvroDeserializer {
    def this(client: SchemaRegistryClient) {
      this()
      this.schemaRegistry = client
    }
    override def deserialize(bytes: Array[Byte]): String = {
      val genericRecord = super.deserialize(bytes).asInstanceOf[GenericRecord]
      genericRecord.toString
    }
  }
}
I think I have to pass this authentication data to CachedSchemaRegistryClient but I'm not sure if so and how.
I've finally been able to pass the properties.
I leave the lines that gave the solution.
val restService = new RestService(schemaRegistryURL)
  val props = Map(
    "basic.auth.credentials.source" -> "USER_INFO",
    "schema.registry.basic.auth.user.info" -> "secret:secret"
  ).asJava
  var schemaRegistryClient = new CachedSchemaRegistryClient(restService, 100, props)
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With